States rethink 'adult time for adult crime' - the Youth Advocacy Division

States rethink 'adult time for adult crime'
By Stephanie Chen, CNN
January 15, 2010 7:37 a.m. EST
This month, Connecticut raised from 16 to 17 the age for juveniles to be automatically
prosecuted in adult court.
STORY HIGHLIGHTS
• 16-year-olds who commit crimes in Connecticut no longer automatically treated as adults
• Illinois also stopped sending 17-year-olds who commit misdemeanors to adult court
• Sentencing experts say sending juveniles to the adult system is becoming less popular
• Juveniles sent to the adult system face criminal records and lack of education
(CNN) -- A year ago, Maydellyn Lamourt watched her 16-year-old son's dreams fall apart.
The outgoing sophomore who enjoyed playing sports was charged and sentenced as an adult in
Connecticut for third-degree assault.
The crime: He and a friend stole a pack of gum from another teen.
Because he entered the adult penal system, the teen's prospects of joining the Marines are dim.
His troubles have landed him in an alternative high school.
If Lamourt's son had committed the crime this month, his situation would be different. His record
would have been sealed in the juvenile system.
Earlier this month, Connecticut raised from 16 to 17 the age at which a juvenile is automatically
prosecuted as an adult. The change comes at a time when the "adult time for adult crime"
mentality is being re-examined in several states and challenged in the U.S. Supreme Court.
Connecticut child advocates say the juvenile system is better suited for teens because it offers
more access to rehabilitative programs, schooling, community-based programming and

supervision from juvenile probation officers. In felony cases, judges can still decide on a caseby-case
basis whether to transfer juveniles younger than 17 to the adult system.
"I was devastated that my son would be in corrections with grown men," said Lamourt. Her son
spent a month at a adult facility that housed juveniles and young adults.
"He feels like from here on down, everything will go downhill," she said.
RELATED TOPICS
U.S. map: Juveniles tried as adults
• Juvenile Justice
• Crime
• Criminal Sentencing and Punishment
This year, the Supreme Court will consider whether juvenile offenses merit adult punishment.
The justices could decide whether juveniles can be sentenced to life without parole for crimes
other than murder. One case involves a Florida inmate, who was convicted of rape at the age of
13 and given a sentence of life without parole.
Juvenile courts have always had the ability to transfer teens and children to the adult system, but
a spike in youth crime during the 1980s and 1990s prompted states to implement mandatory
sentencing policies for certain crimes and lower the age at which a child can be sentenced to
adult court.
Until this year, Connecticut was one of three states, along with New York and North Carolina, to
automatically place teen offenders 16 and older in the adult system. Ten other states
automatically transfer juveniles 17 and older to the adult system -- including South Carolina,
Georgia and Texas.
The decision to raise the age of adult court jurisdiction in Connecticut was spurred by the 2005
suicide of David Burgos. Burgos, a lanky 17-year-old known to family for his sense of humor,
suffered from mental illness when he was charged and sentenced as an adult for violating
probation.
Burgo hung himself with a sheet in his cell at Manson Youth Institution, a corrections facility
that also houses offenders between 18 and 21. His suicide galvanized Connecticut lawmakers to
raise the age in which a juvenile can be moved into adult corrections system.

"When you teach someone to swim, you don't just throw them in the deep end and hope they do
great," said Abby Anderson, executive director of the Connecticut Juvenile Justice Alliance, the
nonprofit agency that spearheaded the campaign to change the law.
When you teach someone to swim, you don't just throw them in the deep end and hope they do
great.
--Abby Anderson, executive director, Connecticut Juvenile Justice Alliance
Originally, Connecticut child advocates pushed legislation that raised the age to 18, but budget
cuts forced the state to raise the age to 17.
The policy shift in Connecticut, a state that once sent the highest number of juveniles to the adult
system, is catching on in other states. This month, Illinois stopped sending 17-year-olds who
commit misdemeanors to the adult system. Instead, the offenders are sent to the juvenile system
where drug treatment and counseling are often required.
In North Carolina, another state where the criminal justice system automatically views 16-yearolds
as adults, a bill was introduced last spring to raise the age a teen can be charged as an adult
to 18. That measure in the bill was rejected, but lawmakers established a task force to study the
proposal with a deadline of 2011.
Meanwhile, lobbying efforts to raise the age continue in other states. In Georgia and Wisconsin,
where a 17-year-old is considered an adult, lawmakers and juvenile advocates have been
working toward change for the past year.
A precise number of how many children are tried in adult court is difficult to ascertain because
states keep records differently, but some experts estimate about a quarter of juveniles are
prosecuted in the adult court system.
On a single day in 2008, more than 7,700 children younger than 18 were held in adult local jails
and 3,600 in adult state prisons, according to a 2009 University of Texas-Austin report.
The juvenile system is based on a rehabilitative approach, compared to the punitive adult system,
child advocates point out. They argue that the adult system teaches juveniles to become adult
criminals, which places the community at risk.
While some states are questioning their juvenile sentencing policies, sentencing experts say
raising the ages or eliminating mandatory sentences remains politically risky. Much of what
states decide to do with their juvenile policies may depend upon Connecticut's outcome.
Jeffrey Fagan, a Columbia University law professor who has studied juvenile crime, said he
thinks reform will come in stages, such as Illinois' new law, which addresses juveniles
committing misdemeanors but not other crimes.
The teenage brain is like a car with a good accelerator but a weak brake.
--Professor Laurence Steinberg, Temple University

"It's easier to sell to the public and implement," Fagan said.
The policy changes in Connecticut occurred largely because of a growing body of brain research
distinguishing the adolescent and adult minds. In 2005, the Supreme Court cited differences in
the adolescent and adult brains as a reason for abolishing the death penalty for juveniles.
Up until the last decade, scientific research on the adolescent brain was largely nonexistent. Led
by professor Laurence Steinberg of Temple University and others in the psychology field, their
research explained why juveniles lack control and understanding of long-term consequence and
are more susceptible to peer pressure.
"The teenage brain is like a car with a good accelerator but a weak brake," Steinberg wrote.
"With powerful impulses under poor control, the likely result is a crash."
Critics argue that sending juveniles to the adult system can deter other teens. They point out that
juvenile crime has declined in recent years.
Maydellyn Lamourt says she warned her son about the dangers of a life of crime, citing mistakes
she had made. Lamourt spent eight months in prison after being convicted of larceny and drug
possession in 2004.
Like her son, the mother knows firsthand the consequences of having a criminal record.
"It follows you for life," she said.

New York Times
March 11, 2007
The Brain on the Stand
By JEFFREY ROSEN
I. Mr. Weinstein’s Cyst When historians of the future try to identify the moment
that neuroscience began to transform the American legal system, they may point
to a little-noticed case from the early 1990s. The case involved Herbert
Weinstein, a 65-year-old ad executive who was charged with strangling his wife,
Barbara, to death and then, in an effort to make the murder look like a suicide,
throwing her body out the window of their 12th-floor apartment on East 72nd
Street in Manhattan. Before the trial began, Weinstein’s lawyer suggested that his
client should not be held responsible for his actions because of a mental defect —
namely, an abnormal cyst nestled in his arachnoid membrane, which surrounds
the brain like a spider web.
The implications of the claim were considerable. American law holds people
criminally responsible unless they act under duress (with a gun pointed at the
head, for example) or if they suffer from a serious defect in rationality — like not
being able to tell right from wrong. But if you suffer from such a serious defect,
the law generally doesn’t care why — whether it’s an unhappy childhood or an
arachnoid cyst or both. To suggest that criminals could be excused because their
brains made them do it seems to imply that anyone whose brain isn’t functioning
properly could be absolved of responsibility. But should judges and juries really
be in the business of defining the normal or properly working brain And since all
behavior is caused by our brains, wouldn’t this mean all behavior could
potentially be excused
The prosecution at first tried to argue that evidence of Weinstein’s arachnoid cyst
shouldn’t be admitted in court. One of the government’s witnesses, a forensic
psychologist named Daniel Martell, testified that brain-scanning technologies
were new and untested, and their implications weren’t yet widely accepted by the
scientific community. Ultimately, on Oct. 8, 1992, Judge Richard Carruthers
issued a Solomonic ruling: Weinstein’s lawyers could tell the jury that brain scans
had identified an arachnoid cyst, but they couldn’t tell jurors that arachnoid cysts
were associated with violence. Even so, the prosecution team seemed to fear that

simply exhibiting images of Weinstein’s brain in court would sway the jury.
Eleven days later, on the morning of jury selection, they agreed to let Weinstein
plead guilty in exchange for a reduced charge of manslaughter.
After the Weinstein case, Daniel Martell found himself in so much demand to
testify as a expert witness that he started a consulting business called Forensic
Neuroscience. Hired by defense teams and prosecutors alike, he has testified over
the past 15 years in several hundred criminal and civil cases. In those cases,
neuroscientific evidence has been admitted to show everything from head trauma
to the tendency of violent video games to make children behave aggressively. But
Martell told me that it’s in death-penalty litigation that neuroscience evidence is
having its most revolutionary effect. “Some sort of organic brain defense has
become de rigueur in any sort of capital defense,” he said. Lawyers routinely
order scans of convicted defendants’ brains and argue that a neurological
impairment prevented them from controlling themselves. The prosecution
counters that the evidence shouldn’t be admitted, but under the relaxed
standards for mitigating evidence during capital sentencing, it usually is. Indeed,
a Florida court has held that the failure to admit neuroscience evidence during
capital sentencing is grounds for a reversal. Martell remains skeptical about the
worth of the brain scans, but he observes that they’ve “revolutionized the law.”
The extent of that revolution is hotly debated, but the influence of what some call
neurolaw is clearly growing. Neuroscientific evidence has persuaded jurors to
sentence defendants to life imprisonment rather than to death; courts have also
admitted brain-imaging evidence during criminal trials to support claims that
defendants like John W. Hinckley Jr., who tried to assassinate President Reagan,
are insane. Carter Snead, a law professor at Notre Dame, drafted a staff working
paper on the impact of neuroscientific evidence in criminal law for President
Bush’s Council on Bioethics. The report concludes that neuroimaging evidence is
of mixed reliability but “the large number of cases in which such evidence is
presented is striking.” That number will no doubt increase substantially.
Proponents of neurolaw say that neuroscientific evidence will have a large impact
not only on questions of guilt and punishment but also on the detection of lies
and hidden bias, and on the prediction of future criminal behavior. At the same
time, skeptics fear that the use of brain-scanning technology as a kind of super

mind-reading device will threaten our privacy and mental freedom, leading some
to call for the legal system to respond with a new concept of “cognitive liberty.”
One of the most enthusiastic proponents of neurolaw is Owen Jones, a professor
of law and biology at Vanderbilt. Jones (who happens to have been one of my
law-school classmates) has joined a group of prominent neuroscientists and law
professors who have applied for a large MacArthur Foundation grant; they hope
to study a wide range of neurolaw questions, like: Do sexual offenders and violent
teenagers show unusual patterns of brain activity Is it possible to capture brain
images of chronic neck pain when someone claims to have suffered whiplash In
the meantime, Jones is turning Vanderbilt into a kind of Los Alamos for
neurolaw. The university has just opened a $27 million neuroimaging center and
has poached leading neuroscientists from around the world; soon, Jones hopes to
enroll students in the nation’s first program in law and neuroscience. “It’s
breathlessly exciting,” he says. “This is the new frontier in law and science —
we’re peering into the black box to see how the brain is actually working, that
hidden place in the dark quiet, where we have our private thoughts and private
reactions — and the law will inevitably have to decide how to deal with this new
technology.”
II. A Visit to Vanderbilt Owen Jones is a disciplined and quietly intense man, and
his enthusiasm for the transformative power of neuroscience is infectious. With
René Marois, a neuroscientist in the psychology department, Jones has begun a
study of how the human brain reacts when asked to impose various punishments.
Informally, they call the experiment Harm and Punishment — and they offered to
make me one of their first subjects.
We met in Jones’s pristine office, which is decorated with a human skull and
calipers, like those that phrenologists once used to measure the human head; his
father is a dentist, and his grandfather was an electrical engineer who collected
tools. We walked over to Vanderbilt’s Institute of Imaging Science, which,
although still surrounded by scaffolding, was as impressive as Jones had
promised. The basement contains one of the few 7-tesla magnetic-resonanceimaging
scanners in the world. For Harm and Punishment, Jones and Marois use
a less powerful 3 tesla, which is the typical research M.R.I.

We then made our way to the scanner. After removing all metal objects —
including a belt and a stray dry-cleaning tag with a staple — I put on earphones
and a helmet that was shaped like a birdcage to hold my head in place. The lab
assistant turned off the lights and left the room; I lay down on the gurney and,
clutching a panic button, was inserted into the magnet. All was dark except for a
screen flashing hypothetical crime scenarios, like this one: “John, who lives at
home with his father, decides to kill him for the insurance money. After
convincing his father to help with some electrical work in the attic, John arranges
for him to be electrocuted. His father survives the electrocution, but he is
hospitalized for three days with injuries caused by the electrical shock.” I was told
to press buttons indicating the appropriate level of punishment, from 0 to 9, as
the magnet recorded my brain activity.
After I spent 45 minutes trying not to move an eyebrow while assigning
punishments to dozens of sordid imaginary criminals, Marois told me through
the intercom to try another experiment: namely, to think of familiar faces and
places in sequence, without telling him whether I was starting with faces or
places. I thought of my living room, my wife, my parents’ apartment and my twin
sons, trying all the while to avoid improper thoughts for fear they would be
discovered. Then the experiments were over, and I stumbled out of the magnet.
The next morning, Owen Jones and I reported to René Marois’s laboratory for
the results. Marois’s graduate students, who had been up late analyzing my brain,
were smiling broadly. Because I had moved so little in the machine, they
explained, my brain activity was easy to read. “Your head movement was
incredibly low, and you were the harshest punisher we’ve had,” Josh Buckholtz,
one of the grad students, said with a happy laugh. “You were a researcher’s dream
come true!” Buckholtz tapped the keyboard, and a high-resolution 3-D image of
my brain appeared on the screen in vivid colors. Tiny dots flickered back and
forth, showing my eyes moving as they read the lurid criminal scenarios.
Although I was only the fifth subject to be put in the scanner, Marois emphasized
that my punishment ratings were higher than average. In one case, I assigned a 7
where the average punishment was 4. “You were focusing on the intent, and the
others focused on the harm,” Buckholtz said reassuringly.

Marois explained that he and Jones wanted to study the interactions among the
emotion-generating regions of the brain, like the amygdala, and the prefrontal
regions responsible for reason. “It is also possible that the prefrontal cortex is
critical for attributing punishment, making the essential decision about what
kind of punishment to assign,” he suggested. Marois stressed that in order to
study that possibility, more subjects would have to be put into the magnet. But if
the prefrontal cortex does turn out to be critical for selecting among
punishments, Jones added, it could be highly relevant for lawyers selecting a jury.
For example, he suggested, lawyers might even select jurors for different cases
based on their different brain-activity patterns. In a complex insider-trading case,
for example, perhaps the defense would “like to have a juror making decisions on
maximum deliberation and minimum emotion”; in a government entrapment
case, emotional reactions might be more appropriate.
We then turned to the results of the second experiment, in which I had been
asked to alternate between thinking of faces and places without disclosing the
order. “We think we can guess what you were thinking about, even though you
didn’t tell us the order you started with,” Marois said proudly. “We think you
started with places and we will prove to you that it wasn’t just luck.” Marois
showed me a picture of my parahippocampus, the area of the brain that responds
strongly to places and the recognition of scenes. “It’s lighting up like Christmas
on all cylinders,” Marois said. “It worked beautifully, even though we haven’t
tried this before here.”
He then showed a picture of the fusiform area, which is responsible for facial
recognition. It, too, lighted up every time I thought of a face. “This is a potentially
very serious legal implication,” Jones broke in, since the technology allows us to
tell what people are thinking about even if they deny it. He pointed to a series of
practical applications. Because subconscious memories of faces and places may
be more reliable than conscious memories, witness lineups could be transformed.
A child who claimed to have been victimized by a stranger, moreover, could be
shown pictures of the faces of suspects to see which one lighted up the facerecognition
area in ways suggesting familiarity.
Jones and Marois talked excitedly about the implications of their experiments for
the legal system. If they discovered a significant gap between people’s hard-wired

sense of how severely certain crimes should be punished and the actual
punishments assigned by law, federal sentencing guidelines might be revised, on
the principle that the law shouldn’t diverge too far from deeply shared beliefs.
Experiments might help to develop a deeper understanding of the criminal brain,
or of the typical brain predisposed to criminal activity.
III. The End of Responsibility Indeed, as the use of functional M.R.I. results
becomes increasingly common in courtrooms, judges and juries may be asked to
draw new and sometimes troubling lines between “normal” and “abnormal”
brains. Ruben Gur, a professor of psychology at the University of Pennsylvania
School of Medicine, specializes in doing just that. Gur began his expert-witness
career in the mid-1990s when a colleague asked him to help in the trial of a
convicted serial killer in Florida named Bobby Joe Long. Known as the
“classified-ad rapist,” because he would respond to classified ads placed by
women offering to sell household items, then rape and kill them, Long was
sentenced to death after he committed at least nine murders in Tampa. Gur was
called as a national expert in positron-emission tomography, or PET scans, in
which patients are injected with a solution containing radioactive markers that
illuminate their brain activity. After examining Long’s PET scans, Gur testified
that a motorcycle accident that had left Long in a coma had also severely
damaged his amygdala. It was after emerging from the coma that Long
committed his first rape.
“I didn’t have the sense that my testimony had a profound impact,” Gur told me
recently — Long is still filing appeals — but he has testified at more than 20
capital cases since then. He wrote a widely circulated affidavit arguing that
adolescents are not as capable of controlling their impulses as adults because the
development of neurons in the prefrontal cortex isn’t complete until the early
20s. Based on that affidavit, Gur was asked to contribute to the preparation of
one of the briefs filed by neuroscientists and others in Roper v. Simmons, the
landmark case in which a divided Supreme Court struck down the death penalty
for offenders who committed crimes when they were under the age of 18.
The leading neurolaw brief in the case, filed by the American Medical Association
and other groups, argued that because “adolescent brains are not fully developed”
in the prefrontal regions, adolescents are less able than adults to control their

impulses and should not be held fully accountable “for the immaturity of their
neural anatomy.” In his majority decision, Justice Anthony Kennedy declared
that “as any parent knows and as the scientific and sociological studies” cited in
the briefs “tend to confirm, ‘[a] lack of maturity and an underdeveloped sense of
responsibility are found in youth more often than in adults.’ ” Although Kennedy
did not cite the neuroscience evidence specifically, his indirect reference to the
scientific studies in the briefs led some supporters and critics to view the decision
as the Brown v. Board of Education of neurolaw.
One important question raised by the Roper case was the question of where to
draw the line in considering neuroscience evidence as a legal mitigation or
excuse. Should courts be in the business of deciding when to mitigate someone’s
criminal responsibility because his brain functions improperly, whether because
of age, in-born defects or trauma As we learn more about criminals’ brains, will
we have to redefine our most basic ideas of justice
Two of the most ardent supporters of the claim that neuroscience requires the
redefinition of guilt and punishment are Joshua D. Greene, an assistant professor
of psychology at Harvard, and Jonathan D. Cohen, a professor of psychology who
directs the neuroscience program at Princeton. Greene got Cohen interested in
the legal implications of neuroscience, and together they conducted a series of
experiments exploring how people’s brains react to moral dilemmas involving life
and death. In particular, they wanted to test people’s responses in the f.M.R.I.
scanner to variations of the famous trolley problem, which philosophers have
been arguing about for decades.
The trolley problem goes something like this: Imagine a train heading toward five
people who are going to die if you don’t do anything. If you hit a switch, the train
veers onto a side track and kills another person. Most people confronted with this
scenario say it’s O.K. to hit the switch. By contrast, imagine that you’re standing
on a footbridge that spans the train tracks, and the only way you can save the five
people is to push an obese man standing next to you off the footbridge so that his
body stops the train. Under these circumstances, most people say it’s not O.K. to
kill one person to save five.

“I wondered why people have such clear intuitions,” Greene told me, “and the
core idea was to confront people with these two cases in the scanner and see if we
got more of an emotional response in one case and reasoned response in the
other.” As it turns out, that’s precisely what happened: Greene and Cohen found
that the brain region associated with deliberate problem solving and self-control,
the dorsolateral prefrontal cortex, was especially active when subjects confronted
the first trolley hypothetical, in which most of them made a utilitarian judgment
about how to save the greatest number of lives. By contrast, emotional centers in
the brain were more active when subjects confronted the second trolley
hypothetical, in which they tended to recoil at the idea of personally harming an
individual, even under such wrenching circumstances. “This suggests that moral
judgment is not a single thing; it’s intuitive emotional responses and then
cognitive responses that are duking it out,” Greene said.
“To a neuroscientist, you are your brain; nothing causes your behavior other than
the operations of your brain,” Greene says. “If that’s right, it radically changes the
way we think about the law. The official line in the law is all that matters is
whether you’re rational, but you can have someone who is totally rational but
whose strings are being pulled by something beyond his control.” In other words,
even someone who has the illusion of making a free and rational choice between
soup and salad may be deluding himself, since the choice of salad over soup is
ultimately predestined by forces hard-wired in his brain. Greene insists that this
insight means that the criminal-justice system should abandon the idea of
retribution — the idea that bad people should be punished because they have
freely chosen to act immorally — which has been the focus of American criminal
law since the 1970s, when rehabilitation went out of fashion. Instead, Greene
says, the law should focus on deterring future harms. In some cases, he supposes,
this might mean lighter punishments. “If it’s really true that we don’t get any
prevention bang from our punishment buck when we punish that person, then
it’s not worth punishing that person,” he says. (On the other hand, Carter Snead,
the Notre Dame scholar, maintains that capital defendants who are not
considered fully blameworthy under current rules could be executed more readily
under a system that focused on preventing future harms.)
Others agree with Greene and Cohen that the legal system should be radically
refocused on deterrence rather than on retribution. Since the celebrated

M’Naughten case in 1843, involving a paranoid British assassin, English and
American courts have recognized an insanity defense only for those who are
unable to appreciate the difference between right and wrong. (This is consistent
with the idea that only rational people can be held criminally responsible for their
actions.) According to some neuroscientists, that rule makes no sense in light of
recent brain-imaging studies. “You can have a horrendously damaged brain
where someone knows the difference between right and wrong but nonetheless
can’t control their behavior,” says Robert Sapolsky, a neurobiologist at Stanford.
“At that point, you’re dealing with a broken machine, and concepts like
punishment and evil and sin become utterly irrelevant. Does that mean the
person should be dumped back on the street Absolutely not. You have a car with
the brakes not working, and it shouldn’t be allowed to be near anyone it can
hurt.”
Even as these debates continue, some skeptics contend that both the hopes and
fears attached to neurolaw are overblown. “There’s nothing new about the
neuroscience ideas of responsibility; it’s just another material, causal explanation
of human behavior,” says Stephen J. Morse, professor of law and psychiatry at
the University of Pennsylvania. “How is this different than the Chicago school of
sociology,” which tried to explain human behavior in terms of environment and
social structures “How is it different from genetic explanations or psychological
explanations The only thing different about neuroscience is that we have prettier
pictures and it appears more scientific.”
Morse insists that “brains do not commit crimes; people commit crimes” — a
conclusion he suggests has been ignored by advocates who, “infected and
inflamed by stunning advances in our understanding of the brain . . . all too often
make moral and legal claims that the new neuroscience . . . cannot sustain.” He
calls this “brain overclaim syndrome” and cites as an example the neuroscience
briefs filed in the Supreme Court case Roper v. Simmons to question the juvenile
death penalty. “What did the neuroscience add” he asks. If adolescent brains
caused all adolescent behavior, “we would expect the rates of homicide to be the
same for 16- and 17-year-olds everywhere in the world — their brains are alike —
but in fact, the homicide rates of Danish and Finnish youths are very different
than American youths.” Morse agrees that our brains bring about our behavior —
“I’m a thoroughgoing materialist, who believes that all mental and behavioral

activity is the causal product of physical events in the brain” — but he disagrees
that the law should excuse certain kinds of criminal conduct as a result. “It’s a
total non sequitur,” he says. “So what if there’s biological causation Causation
can’t be an excuse for someone who believes that responsibility is possible. Since
all behavior is caused, this would mean all behavior has to be excused.” Morse
cites the case of Charles Whitman, a man who, in 1966, killed his wife and his
mother, then climbed up a tower at the University of Texas and shot and killed 13
more people before being shot by police officers. Whitman was discovered after
an autopsy to have a tumor that was putting pressure on his amygdala. “Even if
his amygdala made him more angry and volatile, since when are anger and
volatility excusing conditions” Morse asks. “Some people are angry because they
had bad mommies and daddies and others because their amygdalas are mucked
up. The question is: When should anger be an excusing condition”
Still, Morse concedes that there are circumstances under which new discoveries
from neuroscience could challenge the legal system at its core. “Suppose
neuroscience could reveal that reason actually plays no role in determining
human behavior,” he suggests tantalizingly. “Suppose I could show you that your
intentions and your reasons for your actions are post hoc rationalizations that
somehow your brain generates to explain to you what your brain has already
done” without your conscious participation. If neuroscience could reveal us to be
automatons in this respect, Morse is prepared to agree with Greene and Cohen
that criminal law would have to abandon its current ideas about responsibility
and seek other ways of protecting society.
Some scientists are already pushing in this direction. In a series of famous
experiments in the 1970s and ’80s, Benjamin Libet measured people’s brain
activity while telling them to move their fingers whenever they felt like it. Libet
detected brain activity suggesting a readiness to move the finger half a second
before the actual movement and about 400 milliseconds before people became
aware of their conscious intention to move their finger. Libet argued that this
leaves 100 milliseconds for the conscious self to veto the brain’s unconscious
decision, or to give way to it — suggesting, in the words of the neuroscientist
Vilayanur S. Ramachandran, that we have not free will but “free won’t.”

Morse is not convinced that the Libet experiments reveal us to be helpless
automatons. But he does think that the study of our decision-making powers
could bear some fruit for the law. “I’m interested,” he says, “in people who suffer
from drug addictions, psychopaths and people who have intermittent explosive
disorder — that’s people who have no general rationality problem other than they
just go off.” In other words, Morse wants to identify the neural triggers that make
people go postal. “Suppose we could show that the higher deliberative centers in
the brain seem to be disabled in these cases,” he says. “If these are people who
cannot control episodes of gross irrationality, we’ve learned something that might
be relevant to the legal ascription of responsibility.” That doesn’t mean they
would be let off the hook, he emphasizes: “You could give people a prison
sentence and an opportunity to get fixed.”
IV. Putting the Unconscious on Trial If debates over criminal responsibility long
predate the f.M.R.I., so do debates over the use of lie-detection technology.
What’s new is the prospect that lie detectors in the courtroom will become much
more accurate, and correspondingly more intrusive. There are, at the moment,
two lie-detection technologies that rely on neuroimaging, although the value and
accuracy of both are sharply contested. The first, developed by Lawrence Farwell
in the 1980s, is known as “brain fingerprinting.” Subjects put on an electrodefilled
helmet that measures a brain wave called p300, which, according to
Farwell, changes its frequency when people recognize images, pictures, sights and
smells. After showing a suspect pictures of familiar places and measuring his
p300 activation patterns, government officials could, at least in theory, show a
suspect pictures of places he may or may not have seen before — a Qaeda training
camp, for example, or a crime scene — and compare the activation patterns. (By
detecting not only lies but also honest cases of forgetfulness, the technology could
expand our very idea of lie detection.)
The second lie-detection technology uses f.M.R.I. machines to compare the brain
activity of liars and truth tellers. It is based on a test called Guilty Knowledge,
developed by Daniel Langleben at the University of Pennsylvania in 2001.
Langleben gave subjects a playing card before they entered the magnet and told
them to answer no to a series of questions, including whether they had the card in
question. Langleben and his colleagues found that certain areas of the brain
lighted up when people lied.

Two companies, No Lie MRI and Cephos, are now competing to refine f.M.R.I.
lie-detection technology so that it can be admitted in court and commercially
marketed. I talked to Steven Laken, the president of Cephos, which plans to begin
selling its products this year. “We have two to three people who call every single
week,” he told me. “They’re in legal proceedings throughout the world, and
they’re looking to bolster their credibility.” Laken said the technology could have
“tremendous applications” in civil and criminal cases. On the government side,
he said, the technology could replace highly inaccurate polygraphs in screening
for security clearances, as well as in trying to identify suspected terrorists’ native
languages and close associates. “In lab studies, we’ve been in the 80- to 90-
percent-accuracy range,” Laken says. This is similar to the accuracy rate for
polygraphs, which are not considered sufficiently reliable to be allowed in most
legal cases. Laken says he hopes to reach the 90-percent- to 95-percent-accuracy
range — which should be high enough to satisfy the Supreme Court’s standards
for the admission of scientific evidence. Judy Illes, director of Neuroethics at the
Stanford Center for Biomedical Ethics, says, “I would predict that within five
years, we will have technology that is sufficiently reliable at getting at the binary
question of whether someone is lying that it may be utilized in certain legal
settings.”
If and when lie-detection f.M.R.I.’s are admitted in court, they will raise vexing
questions of self-incrimination and privacy. Hank Greely, a law professor and
head of the Stanford Center for Law and the Biosciences, notes that prosecution
and defense witnesses might have their credibility questioned if they refused to
take a lie-detection f.M.R.I., as might parties and witnesses in civil cases. Unless
courts found the tests to be shocking invasions of privacy, like stomach pumps,
witnesses could even be compelled to have their brains scanned. And equally
vexing legal questions might arise as neuroimaging technologies move beyond
telling whether or not someone is lying and begin to identify the actual content of
memories. Michael Gazzaniga, a professor of psychology at the University of
California, Santa Barbara, and author of “The Ethical Brain,” notes that within 10
years, neuroscientists may be able to show that there are neurological differences
when people testify about their own previous acts and when they testify to
something they saw. “If you kill someone, you have a procedural memory of that,
whereas if I’m standing and watch you kill somebody, that’s an episodic memory
that uses a different part of the brain,” he told me. Even if witnesses don’t have

their brains scanned, neuroscience may lead judges and jurors to conclude that
certain kinds of memories are more reliable than others because of the area of the
brain in which they are processed. Further into the future, and closer to science
fiction, lies the possibility of memory downloading. “One could even, just barely,
imagine a technology that might be able to ‘read out’ the witness’s memories,
intercepted as neuronal firings, and translate it directly into voice, text or the
equivalent of a movie,” Hank Greely writes.
Greely acknowledges that lie-detection and memory-retrieval technologies like
this could pose a serious challenge to our freedom of thought, which is now
defended largely by the First Amendment protections for freedom of expression.
“Freedom of thought has always been buttressed by the reality that you could
only tell what someone thought based on their behavior,” he told me. “This
technology holds out the possibility of looking through the skull and seeing
what’s really happening, seeing the thoughts themselves.” According to Greely,
this may challenge the principle that we should be held accountable for what we
do, not what we think. “It opens up for the first time the possibility of punishing
people for their thoughts rather than their actions,” he says. “One reason thought
has been free in the harshest dictatorships is that dictators haven’t been able to
detect it.” He adds, “Now they may be able to, putting greater pressure on legal
constraints against government interference with freedom of thought.”
In the future, neuroscience could also revolutionize the way jurors are selected.
Steven Laken, the president of Cephos, says that jury consultants might seek to
put prospective jurors in f.M.R.I.’s. “You could give videotapes of the lawyers and
witnesses to people when they’re in the magnet and see what parts of their brains
light up,” he says. A situation like this would raise vexing questions about jurors’
prejudices — and what makes for a fair trial. Recent experiments have suggested
that people who believe themselves to be free of bias may harbor plenty of it all
the same.
The experiments, conducted by Elizabeth Phelps, who teaches psychology at New
York University, combine brain scans with a behavioral test known as the
Implicit Association Test, or I.A.T., as well as physiological tests of the startle
reflex. The I.A.T. flashes pictures of black and white faces at you and asks you to
associate various adjectives with the faces. Repeated tests have shown that white

subjects take longer to respond when they’re asked to associate black faces with
positive adjectives and white faces with negative adjectives than vice versa, and
this is said to be an implicit measure of unconscious racism. Phelps and her
colleagues added neurological evidence to this insight by scanning the brains and
testing the startle reflexes of white undergraduates at Yale before they took the
I.A.T. She found that the subjects who showed the most unconscious bias on the
I.A.T. also had the highest activation in their amygdalas — a center of threat
perception — when unfamiliar black faces were flashed at them in the scanner. By
contrast, when subjects were shown pictures of familiar black and white figures
— like Denzel Washington, Martin Luther King Jr. and Conan O’Brien — there
was no jump in amygdala activity.
The legal implications of the new experiments involving bias and neuroscience
are hotly disputed. Mahzarin R. Banaji, a psychology professor at Harvard who
helped to pioneer the I.A.T., has argued that there may be a big gap between the
concept of intentional bias embedded in law and the reality of unconscious
racism revealed by science. When the gap is “substantial,” she and the U.C.L.A.
law professor Jerry Kang have argued, “the law should be changed to comport
with science” — relaxing, for example, the current focus on intentional
discrimination and trying to root out unconscious bias in the workplace with
“structural interventions,” which critics say may be tantamount to racial quotas.
One legal scholar has cited Phelps’s work to argue for the elimination of
peremptory challenges to prospective jurors — if most whites are unconsciously
racist, the argument goes, then any decision to strike a black juror must be
infected with racism. Much to her displeasure, Phelps’s work has been cited by a
journalist to suggest that a white cop who accidentally shot a black teenager on a
Brooklyn rooftop in 2004 must have been responding to a hard-wired fear of
unfamiliar black faces — a version of the amygdala made me do it.
Phelps herself says it’s “crazy” to link her work to cops who shoot on the job and
insists that it is too early to use her research in the courtroom. “Part of my
discomfort is that we haven’t linked what we see in the amygdala or any other
region of the brain with an activity outside the magnet that we would call racism,”
she told me. “We have no evidence whatsoever that activity in the brain is more
predictive of things we care about in the courtroom than the behaviors
themselves that we correlate with brain function.” In other words, just because

you have a biased reaction to a photograph doesn’t mean you’ll act on those
biases in the workplace. Phelps is also concerned that jurors might be unduly
influenced by attention-grabbing pictures of brain scans. “Frank Keil, a
psychologist at Yale, has done research suggesting that when you have a picture
of a mechanism, you have a tendency to overestimate how much you understand
the mechanism,” she told me. Defense lawyers confirm this phenomenon. “Here
was this nice color image we could enlarge, that the medical expert could point
to,” Christopher Plourd, a San Diego criminal defense lawyer, told The Los
Angeles Times in the early 1990s. “It documented that this guy had a rotten spot
in his brain. The jury glommed onto that.”
Other scholars are even sharper critics of efforts to use scientific experiments
about unconscious bias to transform the law. “I regard that as an extraordinary
claim that you could screen potential jurors or judges for bias; it’s mindboggling,”
I was told by Philip Tetlock, professor at the Haas School of Business
at the University of California at Berkley. Tetlock has argued that split-second
associations between images of African-Americans and negative adjectives may
reflect “simple awareness of the social reality” that “some groups are more
disadvantaged than others.” He has also written that, according to psychologists,
“there is virtually no published research showing a systematic link between racist
attitudes, overt or subconscious, and real-world discrimination.” (A few studies
show, Tetlock acknowledges, that openly biased white people sometimes sit
closer to whites than blacks in experiments that simulate job hiring and
promotion.) “A light bulb going off in your brain means nothing unless it’s
correlated with a particular output, and the brain-scan stuff, heaven help us, we
have barely linked that with anything,” agrees Tetlock’s co-author, Amy Wax of
the University of Pennsylvania Law School. “The claim that homeless people light
up your amygdala more and your frontal cortex less and we can infer that you will
systematically dehumanize homeless people — that’s piffle.”
V. Are You Responsible for What You Might Do The attempt to link unconscious
bias to actual acts of discrimination may be dubious. But are there other ways to
look inside the brain and make predictions about an individual’s future behavior
And if so, should those discoveries be employed to make us safer Efforts to use
science to predict criminal behavior have a disreputable history. In the 19th
century, the Italian criminologist Cesare Lombroso championed a theory of

“biological criminality,” which held that criminals could be identified by physical
characteristics, like large jaws or bushy eyebrows. Nevertheless, neuroscientists
are trying to find the factors in the brain associated with violence. PET scans of
convicted murderers were first studied in the late 1980s by Adrian Raine, a
professor of psychology at the University of Southern California; he found that
their prefrontal cortexes, areas associated with inhibition, had reduced glucose
metabolism and suggested that this might be responsible for their violent
behavior. In a later study, Raine found that subjects who received a diagnosis of
antisocial personality disorder, which correlates with violent behavior, had 11
percent less gray matter in their prefrontal cortexes than control groups of
healthy subjects and substance abusers. His current research uses f.M.R.I.’s to
study moral decision-making in psychopaths.
Neuroscience, it seems, points two ways: it can absolve individuals of
responsibility for acts they’ve committed, but it can also place individuals in
jeopardy for acts they haven’t committed — but might someday. “This opens up a
Pandora’s box in civilized society that I’m willing to fight against,” says Helen S.
Mayberg, a professor of psychiatry, behavioral sciences and neurology at Emory
University School of Medicine, who has testified against the admission of
neuroscience evidence in criminal trials. “If you believe at the time of trial that
the picture informs us about what they were like at the time of the crime, then the
picture moves forward. You need to be prepared for: ‘This spot is a sign of future
dangerousness,’ when someone is up for parole. They have a scan, the spot is
there, so they don’t get out. It’s carved in your brain.”
Other scholars see little wrong with using brain scans to predict violent
tendencies and sexual predilections — as long as the scans are used within limits.
“It’s not necessarily the case that if predictions work, you would say take that guy
off the street and throw away the key,” says Hank Greely, the Stanford law
professor. “You could require counseling, surveillance, G.P.S. transmitters or
warning the neighbors. None of these are necessarily benign, but they beat the
heck out of preventative detention.” Greely has little doubt that predictive
technologies will be enlisted in the war on terror — perhaps in radical ways.
“Even with today’s knowledge, I think we can tell whether someone has a strong
emotional reaction to seeing things, and I can certainly imagine a friend-versusfoe
scanner. If you put everyone who reacts badly to an American flag in a

concentration camp or Guantánamo, that would be bad, but in an occupation
situation, to mark someone down for further surveillance, that might be
appropriate.”
Paul Root Wolpe, who teaches social psychiatry and psychiatric ethics at the
University of Pennsylvania School of Medicine, says he anticipates that
neuroscience predictions will move beyond the courtroom and will be used to
make predictions about citizens in all walks of life.
“Will we use brain imaging to track kids in school because we’ve discovered that
certain brain function or morphology suggests aptitude” he asks. “I work for
NASA, and imagine how helpful it might be for NASA if it could scan your brain
to discover whether you have a good enough spatial sense to be a pilot.” Wolpe
says that brain imaging might eventually be used to decide if someone is a worthy
foster or adoptive parent — a history of major depression and cocaine abuse can
leave telltale signs on the brain, for example, and future studies might find parts
of the brain that correspond to nurturing and caring.
The idea of holding people accountable for their predispositions rather than their
actions poses a challenge to one of the central principles of Anglo-American
jurisprudence: namely, that people are responsible for their behavior, not their
proclivities — for what they do, not what they think. “We’re going to have to make
a decision about the skull as a privacy domain,” Wolpe says. Indeed, Wolpe
serves on the board of an organization called the Center for Cognitive Liberty and
Ethics, a group of neuroscientists, legal scholars and privacy advocates
“dedicated to protecting and advancing freedom of thought in the modern world
of accelerating neurotechnologies.”
There may be similar “cognitive liberty” battles over efforts to repair or enhance
broken brains. A remarkable technique called transcranial magnetic stimulation,
for example, has been used to stimulate or inhibit specific regions of the brain. It
can temporarily alter how we think and feel. Using T.M.S., Ernst Fehr and Daria
Knoch of the University of Zurich temporarily disrupted each side of the
dorsolateral prefrontal cortex in test subjects. They asked their subjects to
participate in an experiment that economists call the ultimatum game. One
person is given $20 and told to divide it with a partner. If the partner rejects the

proposed amount as too low, neither person gets any money. Subjects whose
prefrontal cortexes were functioning properly tended to reject offers of $4 or less:
they would rather get no money than accept an offer that struck them as insulting
and unfair. But subjects whose right prefrontal cortexes were suppressed by
T.M.S. tended to accept the $4 offer. Although the offer still struck them as
insulting, they were able to suppress their indignation and to pursue the selfishly
rational conclusion that a low offer is better than nothing.
Some neuroscientists believe that T.M.S. may be used in the future to enforce a
vision of therapeutic justice, based on the idea that defective brains can be cured.
“Maybe somewhere down the line, a badly damaged brain would be viewed as
something that can heal, like a broken leg that needs to be repaired,” the
neurobiologist Robert Sapolsky says, although he acknowledges that defining
what counts as a normal brain is politically and scientifically fraught. Indeed,
efforts to identify normal and abnormal brains have been responsible for some of
the darkest movements in the history of science and technology, from phrenology
to eugenics. “How far are we willing to go to use neurotechnology to change
people’s brains we consider disordered” Wolpe asks. “We might find a part of
the brain that seems to be malfunctioning, like a discrete part of the brain
operative in violent or sexually predatory behavior, and then turn off or inhibit
that behavior using transcranial magnetic stimulation.” Even behaviors in the
normal range might be fine-tuned by T.M.S.: jurors, for example, could be made
more emotional or more deliberative with magnetic interventions. Mark George,
an adviser to the Cephos company and also director of the Medical University of
South Carolina Center for Advanced Imaging Research, has submitted a patent
application for a T.M.S. procedure that supposedly suppresses the area of the
brain involved in lying and makes a person less capable of not telling the truth.
As the new technologies proliferate, even the neurolaw experts themselves have
only begun to think about the questions that lie ahead. Can the police get a search
warrant for someone’s brain Should the Fourth Amendment protect our minds
in the same way that it protects our houses Can courts order tests of suspects’
memories to determine whether they are gang members or police informers, or
would this violate the Fifth Amendment’s ban on compulsory self-incrimination
Would punishing people for their thoughts rather than for their actions violate
the Eighth Amendment’s ban on cruel and unusual punishment However

astonishing our machines may become, they cannot tell us how to answer these
perplexing questions. We must instead look to our own powers of reasoning and
intuition, relatively primitive as they may be. As Stephen Morse puts it,
neuroscience itself can never identify the mysterious point at which people
should be excused from responsibility for their actions because they are not able,
in some sense, to control themselves. That question, he suggests, is “moral and
ultimately legal,” and it must be answered not in laboratories but in courtrooms
and legislatures. In other words, we must answer it ourselves.
Jeffrey Rosen, a frequent contributor, is the author most recently of “The
Supreme Court: The Personalities and Rivalries That Defined America.”

Brain science offers insight to teen crime : Special Reports : Albuquerque Tribune
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Brain science offers insight to teen crime
By Joline Gutierrez Krueger (Contact)
Friday, December 8, 2006
Should Michael Brown have
been given such a harsh adult
sentence for his role in the
deaths of his grandparents
Yes
No
See the results without voting ».
Smart Box
Thinking like a teen
Scientists and members of the
juvenile justice system are giving
greater thought to whether
differences between the brain of an
adolescent and that of an adult
should have different implications
for each in the criminal justice
system.
Amygdala: The brain's emotional
center, which controls anger, fear,
recklessness, among other
reactions. In teens, the activity
here is in high gear. In adults, it's
tempered by a more developed
frontal lobe.
Frontal lobe: The brain's executive
center, which includes the
prefrontal cortex, responsible for
anticipating consequences,
http://www.abqtrib.com/news/2006/dec/08/brain-science-offers-insight-teen-crime/ (1 of 6)12/15/2006 2:32:28 PM
What was
Michael Brown
thinking
Jurors pondered
that nearly 12
years ago before
deciding on the
guilty verdict that
would lock the
teen away for
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Brain science offers insight to teen crime : Special Reports : Albuquerque Tribune
planning and controlling impulses.
In short, it keeps the amygdala in
check. In teens, however, this area
is barely functioning and will not be
fully developed until age 20 to 25.
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decades in an
adult prison.
They questioned
why a 16-yearold
boy with no previous history of violence did nothing to stop his teen pals from stabbing his screaming
grandparents in 1994 unless he was the cold and calculating killer prosecutors said he was.
But if the trial took place now or years from now, would science have played a greater role in their deliberating
Would Brown have been saved from the adult sanctions because of his teenage brain
Advances in brain research suggest it's possible.
Scientists are now seeing beyond the skull into an emerging debate over whether the differences between the
brain of an adolescent and an adult should have different implications for each in the criminal justice system.
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Studies being conducted at institutions such as the Laboratory for Adolescent Science at Dartmouth College and
the National Institute of Mental Health in Bethesda, Md., could someday lead to the development of tools to aid in
determining juvenile offenders' degree of culpability as compared with adults.
That could mean future Michael Browns will have an additional argument for receiving juvenile sanctions, not
adult sentences, in cases of kids who kill.
"We are interested in the broader question of whether juveniles should be punished to the same extent as adults
who have committed comparable crimes," said psychologist Laurence Steinberg in his 2003 article, "Less Guilty
by Reason of Adolescence."
Take a "CSI" look into the teenage brain and you'll notice a firestorm of activity. But experts say it's where that
http://www.abqtrib.com/news/2006/dec/08/brain-science-offers-insight-teen-crime/ (2 of 6)12/15/2006 2:32:28 PM

Brain science offers insight to teen crime : Special Reports : Albuquerque Tribune
activity is taking place - and where it isn't - that makes the crucial difference.
The gray matter chatter in a teen brain is in full swing deep within the temporal lobe in an almond-shaped bulge
called the amygdala, the brain's emotional center.
In adults, the amygdala's emotional and often impulsive or erratic reactions such as anger, fear and recklessness
are tempered by the reasoning and social awareness of the brain's frontal lobe.
Cerebral construction is not complete until around ages 20 to 25, most scientists agree. The frontal lobe is one of
the last areas of the brain to develop.
In the adolescent brain, it's barely firing at all.
Without the frontal lobe on board, it becomes physiologically harder for a teen to completely understand the
future consequences of his or her emotional or impulsive actions, scientists contend.
"Thus, there is good reason to believe that adolescents, as compared with adults, are more susceptible to
influence, less future-oriented, less risk averse and less able to manage their impulses and behavior," Steinberg
said.
He and others advocate that such a discrepancy in brain function should be taken into consideration when
deciding to seek juvenile or adult sanctions.
Childhood abuse and neglect further hampers normal brain development, researchers say. A recent study by the
Juvenile Justice Center of the American Bar Association found that a majority of juveniles on death rows across
the country had been abused or neglected as children.
A U.S. Supreme Court decision last year now prohibits sentencing a juvenile to death, a decision that took into
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Brain science offers insight to teen crime : Special Reports : Albuquerque Tribune
consideration the incomplete brain development in juveniles. Court observers say that decision could have
striking implications in cases where adult sanctions are being sought for juvenile offenders.
No one is saying, however, that an immature brain is an excuse for committing crime - nor does it exonerate a
juvenile from the consequences of breaking the law.
It "does not excuse violent criminal behavior, but it's an important factor for courts to consider," according to a
statement from the American Psychiatric Association.
Chief Bernalillo County Deputy District Attorney Todd Heisey warns that brain science cannot predict which teen
can be rehabilitated and which is a budding psychopath.
"I think it's too soon to simply rely on that sort of technology," he said. "Some kids are just violent; some kids can
get better once they face their consequences. The trick is to know which is which."
Presiding Children's Court Judge Marie Baca said she is beginning to see more discussion of the juvenile brain in
her Albuquerque courtroom.
"It's a controversial area," said Baca. "It's hard to go from this tough-love position where we hold juveniles
accountable for their actions, including murder. But it's important, I think, to realize that children don't behave like
little adults."
State District Judge Louis McDonald, who sentenced Brown and his two teen co-defendants as adults, said the
brain-science debate has yet to enter his courtroom, located in Bernalillo.
Still, he said he tries to keep up with current research on the issue.
"The difficult thing about sentencing kids is everything I've seen about teenagers is that their brains are not
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Brain science offers insight to teen crime : Special Reports : Albuquerque Tribune
complete," he said. "There is so much going on in there. They act impulsively. Sometimes they do things they've
never even reflected on."
McDonald said he doubts Brown and the other two, Bernadette Setser and Jeremy Rose, know to this day why
they did what they did on a February night nearly 13 years ago when they took two lives and tossed away their
own.
"They don't understand what they were thinking," he said.
Brain research suggests that the question they should be asking is not what they were thinking but how they
were thinking.
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Brain Maturation and the Execution of Juveniles
Some reflections on science and the law.
Illustration ©David Hollenbach
issue.
By Ruben C. Gur | By Ruben C. Gur | Should the death penalty be applied to
offenders who were “juvenile” but over the age of 16 when they committed
their crimes As I am writing, the U.S. Supreme Court is deliberating this
The attorneys arguing against juvenile execution used evidence from research on brain
development to claim that the juvenile brain is insufficiently mature in areas relevant to
criminal culpability to warrant the ultimate punishment. This is how I was dragged out
of my hiding in the laboratory and into the midst of legal deliberations, culminating in
amicus briefs and conferences with glitzy legal teams.
The first hint of the storm came two years ago, with a call from a lawyer, Marc Bookman
C’78, from the Defender Association of Philadelphia. He asked if I knew of or could
prepare a review of the literature on brain development; he needed one to help a

Pennsylvania man who was facing the death penalty for crimes committed as a juvenile.
I happened to have reviewed this literature for a manuscript reporting our own data
from longitudinal studies performed by Penn’s Brain Behavior Laboratory and the
Schizophrenia Center, and so I agreed to augment it and make it more readable for nonexperts.
He sent it back to me, this time formatted as an affidavit in the case of a Mr.
Hector Huertas. He asked whether I would mind reviewing the affidavit and, if I agreed
with its contents, to notarize and sign it. Well, I agreed and it apparently worked. The
Commonwealth decided not to pursue the death penalty in light of scientific findings
that the brain does not mature until early adulthood. Soon afterward Mr. Bookman
called again, this time to help a colleague in Texas who was defending a Mr. Toronto
Patterson, a death-row inmate who also committed his crime when he was an
adolescent.
The affidavit did not save Mr. Patterson’s life, but while the U.S. Supreme Court refused
to hear the appeal, it expressed interest in the scientific evidence from brain research
that was presented in the case, and invited such arguments in future cases. The race was
on to see what would be the test case determining whether the death penalty will apply
to juvenile defendants, and I found myself being asked to sign affidavits from around
the country. The “winner” was a Missouri man, Mr. Christopher Simmons (Roper v.
Simmons). Below is a summary of the material I have submitted as part of an amicus
organized by Mr. Simmons’ defense:
The rate at which the human brain matures has been of considerable interest to
neuroscientists, and knowledge of when different brain regions mature in human
development may have profound implications for understanding behavioral
development. Although the brain and its structure become well differentiated during
fetal development, there is overwhelming evidence that much of the maturational
process occurs after birth. Indeed, projections from early pioneering work on donated
brain tissue have indicated that some brain regions do not reach maturity in humans
until adulthood. These projections have been confirmed by more recent neuroimaging
studies.
While sophisticated methods for preservation and dissection of postmortem brain tissue
had been developed in the first decades of the 20th century, it was not until the 1960s
that enough such tissue was available to examine the question of brain maturation in
humans. Arguably the largest collection and the most influential work was that of Dr.
Paul I. Yakovlev and his colleagues at Harvard University. His work has focused on the
creation of myelin, fatty tissue surrounding nerve fibers. This process, known as
myelogenesis, is important for assuring efficient transmission of neuronal signals;
myelin surrounds the nerve fibers that carry information across large distances very
much in the same way that rubber is used for insulating cables designed to conduct
electricity across distance.
Yakovlev examined slices of brain tissue from a wide age range of more than 200 brains,
finding that especially late to myelinate were those parts of the brain that inhibit and
modulate the more primitive, drive-related activation of the limbic areas. As interpreted
by Yakovlev and his colleagues, the anatomic data indicated that the very functions that

make us uniquely human are the latest to become fully integrated into the workings of
the developing brain.
University of Chicago researcher Peter Huttenlocher uncovered another
neurodevelopmental phenomenon apparently taking place during adolescence:
pruning. According to the pruning hypothesis, neurons and their connections that have
not been consistently used during childhood “shrivel off” and are eliminated at some
point during adolescence, thereby allowing for greater efficiency of the remaining neural
systems.
Postmortem tissue studies have contributed important insights into understanding
brain maturation, but they have serious limitations, including tissue availability and the
inability to trace developmental changes in the same individual.
These difficulties are circumvented by a set of novel techniques—developed in the 1970s
and fully implemented by the 1990s—that can be generally referred to as structural
imaging. These methods permit visualization and volumetric measurement of brain
structure in living people without any risk to the subjects. The method that has become
state-of-the-art for these studies is based on magnetic resonance imaging (MRI)
procedures. MRI has provided data on the composition of three brain components, or
compartments: gray matter—nerve tissue responsible for information processing; white
matter—nerve tissue responsible for information transmission; and cerebrospinal fluid.
This division of the brain into these compartments is termed segmentation.
In one of the first studies examining segmented MRI in children and adults, researchers
Terry Jernigan and Paula Tallal from the University of California have documented the
pruning process. They found that children had higher volumes of gray matter than
adults, indicating loss of gray matter during adolescence. In another study Stanford
researchers Adolph Pfefferbaum and Calvin Lim demonstrated a clearly different
developmental course for gray matter and white matter: The former declined steadily
during adolescence while the latter increased in volume until about 20-22 years of age.
A subsequent NIH study led by Judith Rappoport pinpointed the greatest delay in
myelination for the brain’s fronto-temporal pathways.
In the only study to date that examined segmented MRI volumes from a prospective
sample of 28 healthy children aged one month to 10 years, as well as a small adult
sample, researchers from Penn and Toyama University in Japan applied segmentation
procedures developed by the Penn group. This, actually, was the very study that
prompted me to write a review of the literature, which I used for Mr. Bookman’s
request. We found that while gray matter volume peaked at about two years of age, the
volume of white matter, which indicates brain maturation, continued to increase into
adulthood. Furthermore, we found that the frontal lobe showed the greatest
maturational lag and its myelination is unlikely to be completed before young
adulthood.
Most recently, investigators at UCLA’s brain imaging center analyzed MRI scans of 13
healthy children over a period of eight to 10 years. They concluded that brain areas in

the cerebral cortex, responsible for higher-order integration, mature only after lowerorder
somatosensory and visual cortices are developed.
My review of the data found overwhelming evidence indicating that the main index of
maturation, which is the process called myelination, is not complete until some time in
the beginning of the third decade of life (probably at around ages 20-22). Other
maturational processes, such as the increase and subsequent elimination (“pruning”) in
cell number and connectivity, may be completed by late adolescence, perhaps by ages
15-17. (More data are needed to know for sure.) These results have rather profound
implications for understanding behavioral development. The cortical regions that are
last to mature, particularly those in prefrontal areas, are involved in behavioral facets
germane to many aspects of criminal culpability. Perhaps most relevant is the
involvement of these brain regions in the control of aggression and other impulses, the
process of planning for long-range goals, organization of sequential behavior, the
process of abstraction and mental flexibility, and aspects of memory including “working
memory.” If the neural substrates of these behaviors have not reached maturity before
adulthood, it is unreasonable to expect the behaviors themselves to reflect mature
thought processes.
As I stated in my expert opinion for the court, the brain-scan techniques have
demonstrated conclusively that the phenomena observed by mental-health
professionals in persons under 18, which would render them less morally blameworthy
for offenses, have a scientific grounding in neural substrates.
The evidence now is strong that the brain does not cease to mature until the early 20s in
those relevant parts that govern impulsivity, judgment, planning for the future, foresight
of consequences, and other characteristics that make people morally culpable.
Therefore, from the perspective of neural development, someone under 20 should be
considered to have an underdeveloped brain. Additionally, since brain development in
the relevant areas goes in phases that vary in rate and is usually not complete before the
early to mid-20s, there is no way to state with any scientific reliability that an individual
17-year-old has a fully matured brain (and should be eligible for the most severe
punishment), no matter how many otherwise accurate tests and measures might be
applied to him at the time of his trial for capital murder. This is similar to other physical
characteristics such as height. While we know the age at which the average adult reaches
his or her maximal height, predictions for individuals are not easy to make. Thus,
although 18 is an arbitrary cutoff, given the ongoing development of the brain in most
individuals, it must be preferred over 17 to assure that only the most culpable are
punished for capital crimes. Indeed, age 21 or 22 would be closer to the “biological” age
of maturity.
Dr. Ruben Gur is a professor of psychology in the Department of Psychiatry (with secondary appointments in Radiology
and Neurology) and director of the Brain Behavior Laboratory in the School of Medicine.
©2005 The Pennsylvania Gazette
Last modified 01/05/05

New research shows stark differences in teen brains
New research shows stark differences in teen
brains
Lee Bowman, Scripps Howard
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Written by: Lee Bowman, Scripps Howard
May 11, 2004:
Scripps Howard News Service
New research shows stark differences in teen brains
By Lee Bowman
Recent popular films depicting teenagers suddenly housed in adult bodies have more
than a little truth in them.
The latest brain research has found strong evidence that when it comes to maturity,
organization and control, key parts of the brain related to emotions, judgment and
"thinking ahead" are the last to arrive.
"It seems that regulation of impulse control is the last on board and often the first to
leave in the brain as we age," said Dr. Ruben Gur, a professor of psychology and
director of the Brain Behavior Laboratory at the University of Pennsylvania who has
been researching brain development in young adults.
Until recently, most brain experts thought the human command center stopped
growing at around 18 months, and that neurons were pretty much set for life by age
3.
In fact, the brain's gray matter has a final growth spurt around the ages of 11 to 13
in the frontal lobes of the brain, the regions that guide human intellect and planning.
But it seems to take most of the teen years for youngsters to link these new cells to
the rest of their brains and solidify the millions of connections that allow them to
think and behave like adults.
At the same time, the release of a cascade of adolescent hormones during and after
puberty causes other areas of the brain, particularly the amygdala, which governs
basic emotional response, to fire up or expand.
The result is that teens look at things differently than adults. This has tremendous
implications for education, mental health, drug abuse and moral and legal
responsibility of adolescents.
Deborah Yurgelun-Todd of Harvard Medical School and McClean Hospital in Boston
has studied how teenagers and adults respond differently to the same images.
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New research shows stark differences in teen brains
Shown a set of photos of people's faces contorted in fear, adults named the right
emotion, but teens seldom did, often saying the person was angry.
When Yurgelun-Todd and her team did the same test while doing functional
magnetic resonance imaging of the subject's brains, they found a stark difference in
the parts being used. Adults used both the advanced prefrontal cortex and the more
basic amygdala to evaluate what they had seen; younger teens relied entirely on the
amygdala, while older teens (top age in the group was 17) showed a progressive
shift toward using the frontal area of the brain.
"Just because teens are physically mature, they may not appreciate the
consequences or weigh information the same way as adults do," Yurgelun-Todd said.
"Good judgment is learned, but you can't learn it if you don't have the necessary
hardware."
There is more evidence of the differences:
●
A recent imaging study by researchers at the National Institute on Alcohol
Abuse and Alcoholism found that teens taking an experimental gambling test
are less likely to activate a region in the base of the brain that motivates
behavior to work to obtain rewards than a control group of young adults, ages
22-28, playing the same games.
●
Numerous studies show alcohol and perhaps other drugs hit teen brains harder
than they do adult brains. The frontal lobes and the hippocampus, which is
involved in memory formation, are particularly vulnerable.
●
It has been known for some time that children have sharp growth spurts in
brain connections among regions specialized for language and spatial
relationships between ages 6 and 12. That language capacity tends to reside
mostly in a person's nondominant side - the left hemisphere of the brain in
right-handers, for instance. But a recent imaging study by researchers at the
University of Cincinnati Medical Center found that this distinction ends in the
mid-20s when the brain shifts to use both sides in language processing.
The story of teen brain development lies in a process called myelinization, in which a
layer of fat coats wire-like fibers connecting regions of the brain, back-to-front, sideto-side,
and everywhere in between. Over time, this makes the operation of the
brain more precise and efficient, affecting not just thinking and problem-solving, but
also coordination and mastery of skills ranging from throwing a baseball to playing
the trombone.
But there's a price for this greater efficiency -brain cells that aren't hooked up to
other parts tend to get killed off.
"If they're not on the network, they die and their place is taken up with cerebral
fluid. This goes on well beyond age 18," said Dr. David Fassler, a psychiatrist at the
University of Vermont.
Even in adulthood, the wiring job is not completely done. Imaging done on the
brains of people in their 40s and 50s show there's another surge of connections
being made, perhaps in response to menopause or to prepare the brain to better
compensate for the loss of brain cells as we age.
Still, it's a slow, arduous road to maturity and insight for teens.
"We have some new insight into the 16 year-old that doesn't think twice about
getting in a car with a friend who's been drinking, but they're still not going to
appreciate adults arguments for why they shouldn't," said Fassler.
At the National Institute of Mental Health, Dr. Jay Giedd, who helps run the ongoing
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New research shows stark differences in teen brains
imaging studies that first detected the middle school growth spurt, said the new
understanding of teen brains "argues for doing a lot of things as a teenager. You are
hard-wiring you brain in adolescence. Do you want to hard-wire it for sports and
playing music and doing mathematics, or for lying on the couch in front of the
television"
The new understanding of adolescent brains leads to questions of ethics and
legalities.
The Supreme Court already has decided that people should not be executed for
crimes committed when they were age 15 or younger, and in the fall is scheduled to
consider whether the restriction should be extended to everyone under 18.
Two years ago, the court banned execution of mentally retarded people because of
deficiencies that "diminish their personal culpability."
"With the new biological explanation that adolescent brains are different, we think
there's scientific evidence that they, too, are less culpable," said Stephen Harper, an
adjunct professor of juvenile justice at the University of Miami School of Law who
specializes in capital cases.
Gur said some scientists would put off the age of legal majority to 22 or 23, and said
there will likely be considerable debate over how to tell when a person's brain
physically looks like an adult's as imaging research continues and efforts to set
standards and norms develop.
Fassler predicts that within a decade, brain images will be sophisticated enough to
"help us determine the age for appropriate treatment of addictions and therapy
models for adults and adolescents with disorders."
Other researchers say that while it's possible to gain general understanding about
brain development and function from the images, the notion that medicine, law
enforcement or anyone else should work from some ideal, normal brain model is
troubling.
"Each individual is not an exact map, and the difficulties in determining what the
range of variations are is really dangerous. The data is incredibly easy to be overinterpreted,"
said Sonia Miller, a New York attorney who specializes in cases dealing
with new technologies.
Some courts are already accepting brain scans as evidence of a person's mental
capacity in criminal cases, she said, and "as the neuroscience of intentional behavior
develops, the way we assign responsibility and blame will be challenged. This raises
a lot of questions about how much neural privacy can we expect, how much the
authorities can get into your brain."
Dr. Peter Bandettini, a brain-imaging researcher at the National Institutes of Health,
said the science of understanding what small structures and chemicals are doing
within the brain is far from a gold standard for mental function or age.
"Right now, I personally think you'd get more information about a person's mental
age by going to a set of behavioral tests. But I'd agree that as these technologies
become more powerful, there's going to be a greater need for checks and balances
to determine how the imaging information should be used."
On the Net:
●
●
●
●
http://www.nimh.nih.gov/
http://www.dana.org/
http://www.aap.org/
http://www.psych.org/
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What Makes Teens Tick; A flood of hormones, sure. But also a host of struct...plain the behaviors that make adolescence so exciting--and so exasperating
What Makes Teens Tick; A flood of hormones,
sure. But also a host of structural changes in the
brain. Can those explain the behaviors that
make adolescence so exciting--and so
exasperating
Advanced search |
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Time Magazine
Written by: Time Magazine
Time Magazine
May 10, 2004
What Makes Teens Tick; A flood of hormones, sure. But also a
host of structural changes in the brain. Can those explain the
behaviors that make adolescence so exciting--and so
exasperating
By Claudia Wallis; Kristina Dell, with reporting by Alice Park/New York
Five young men in sneakers and jeans troop into a waiting room at the National
Institutes of Health Clinical Center in Bethesda, Md., and drape themselves all over
the chairs in classic collapsed-teenager mode, trailing backpacks, a CD player and a
laptop loaded with computer games. It's midafternoon, and they are, of course,
tired, but even so their presence adds a jangly, hormonal buzz to the bland,
institutional setting. Fair-haired twins Corey and Skyler Mann, 16, and their burlier
big brothers Anthony and Brandon, 18, who are also twins, plus eldest brother
Christopher, 22, are here to have their heads examined. Literally. The five brothers
from Orem, Utah, are the latest recruits to a giant study that's been going on in this
building since 1991. Its goal: to determine how the brain develops from childhood
into adolescence and on into early adulthood.
It is the project of Dr. Jay Giedd (pronounced Geed), chief of brain imaging in the
child psychiatry branch at the National Institute of Mental Health. Giedd, 43, has
devoted the past 13 years to peering inside the heads of 1,800 kids and teenagers
using high-powered magnetic resonance imaging (MRI). For each volunteer, he
creates a unique photo album, taking MRI snapshots every two years and building a
record as the brain morphs and grows. Giedd started out investigating the
developmental origins of attention-deficit/hyperactivity disorder (ADHD) and autism
("I was going alphabetically," he jokes) but soon discovered that so little was known
about how the brain is supposed to develop that it was impossible to figure out
where things might be going wrong. In a way, the vast project that has become his
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What Makes Teens Tick; A flood of hormones, sure. But also a host of struct...plain the behaviors that make adolescence so exciting--and so exasperating
life's work is nothing more than an attempt to establish a gigantic control group. "It
turned out that normal brains were so interesting in themselves," he marvels. "And
the adolescent studies have been the most surprising of all."
Before the imaging studies by Giedd and his collaborators at UCLA, Harvard, the
Montreal Neurological Institute and a dozen other institutions, most scientists
believed the brain was largely a finished product by the time a child reached the age
of 12. Not only is it full-grown in size, Giedd explains, but "in a lot of psychological
literature, traced back to [Swiss psychologist Jean] Piaget, the highest rung in the
ladder of cognitive development was about age 12--formal operations." In the past,
children entered initiation rites and started learning trades at about the onset of
puberty. Some theorists concluded from this that the idea of adolescence was an
artificial construct, a phenomenon invented in the post--Industrial Revolution years.
Giedd's scanning studies proved what every parent of a teenager knows: not only is
the brain of the adolescent far from mature, but both gray and white matter undergo
extensive structural changes well past puberty. "When we started," says Giedd, "we
thought we'd follow kids until about 18 or 20. If we had to pick a number now, we'd
probably go to age 25."
Now that MRI studies have cracked open a window on the developing brain,
researchers are looking at how the newly detected physiological changes might
account for the adolescent behaviors so familiar to parents: emotional outbursts,
reckless risk taking and rule breaking, and the impassioned pursuit of sex, drugs and
rock 'n' roll. Some experts believe the structural changes seen at adolescence may
explain the timing of such major mental illnesses as schizophrenia and bipolar
disorder. These diseases typically begin in adolescence and contribute to the high
rate of teen suicide. Increasingly, the wild conduct once blamed on "raging
hormones" is being seen as the by-product of two factors: a surfeit of hormones,
yes, but also a paucity of the cognitive controls needed for mature behavior.
In recent years, Giedd has shifted his focus to twins, which is why the Manns are
such exciting recruits. Although most brain development seems to follow a set plan,
with changes following cues that are preprogrammed into genes, other, subtler
changes in gray matter reflect experience and environment. By following twins, who
start out with identical--or, in fraternal twins, similar--programming but then diverge
as life takes them on different paths, he hopes to tease apart the influences of
nature and nurture. Ultimately, he hopes to find, for instance, that Anthony Mann's
plan to become a pilot and Brandon's to study law will lead to brain differences that
are detectable on future MRIs. The brain, more than any other organ, is where
experience becomes flesh.
Throughout the afternoon, the Mann brothers take turns completing tests of
intelligence and cognitive function. Between sessions they occasionally needle one
another in the waiting room. "If the other person is in a bad mood, you've got to
provoke it," Anthony asserts slyly. Their mother Nancy Mann, a sunny paragon of
patience who has three daughters in addition to the five boys, smiles and rolls her
eyes.
Shortly before 5 p.m., the Manns head downstairs to the imaging floor to meet the
magnet. Giedd, a trim, energetic man with a reddish beard, twinkly blue eyes and an
impish sense of humor, greets Anthony and tells him what to expect. He asks
Anthony to remove his watch, his necklace and a high school ring, labeled KEEPER.
Does Anthony have any metal in his body Any piercings Not this clean-cut, soccerplaying
Mormon. Giedd tapes a vitamin E capsule onto Anthony's left cheek and one
in each ear. He explains that the oil-filled capsules are opaque to the scanner and
will define a plane on the images, as well as help researchers tell left from right. The
scanning will take about 15 minutes, during which Anthony must lie completely still.
Dressed in a red sweat shirt, jeans and white K-Swiss sneakers, he stretches out on
the examining table and slides his head into the machine's giant magnetic ring.
MRI, Giedd points out, "made studying healthy kids possible" because there's no
radiation involved. (Before MRI, brain development was studied mostly by using
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What Makes Teens Tick; A flood of hormones, sure. But also a host of struct...plain the behaviors that make adolescence so exciting--and so exasperating
cadavers.) Each of the Mann boys will be scanned three times. The first scan is a
quick survey that lasts one minute. The second lasts two minutes and looks for any
damage or abnormality. The third is 10 minutes long and taken at maximum
resolution. It's the money shot. Giedd watches as Anthony's brain appears in cross
section on a computer screen. The machine scans 124 slices, each as thin as a dime.
It will take 20 hours of computer time to process the images, but the analysis is
done by humans, says Giedd. "The human brain is still the best at pattern
recognition," he marvels.
Some people get nervous as the MRI machine clangs noisily. Claustrophobes panic.
Anthony, lying still in the soul of the machine, simply falls asleep.
CONSTRUCTION AHEAD
One reason scientists have been surprised by the ferment in the teenage brain is
that the brain grows very little over the course of childhood. By the time a child is 6,
it is 90% to 95% of its adult size. As a matter of fact, we are born equipped with
most of the neurons our brain will ever have--and that's fewer than we have in
utero. Humans achieve their maximum brain-cell density between the third and sixth
month of gestation--the culmination of an explosive period of prenatal neural
growth. During the final months before birth, our brains undergo a dramatic pruning
in which unnecessary brain cells are eliminated. Many neuroscientists now believe
that autism is the result of insufficient or abnormal prenatal pruning.
What Giedd's long-term studies have documented is that there is a second wave of
proliferation and pruning that occurs later in childhood and that the final, critical part
of this second wave, affecting some of our highest mental functions, occurs in the
late teens. Unlike the prenatal changes, this neural waxing and waning alters not the
number of nerve cells but the number of connections, or synapses, between them.
When a child is between the ages of 6 and 12, the neurons grow bushier, each
making dozens of connections to other neurons and creating new pathways for nerve
signals. The thickening of all this gray matter--the neurons and their branchlike
dendrites--peaks when girls are about 11 and boys 12 1/2, at which point a serious
round of pruning is under way. Gray matter is thinned out at a rate of about 0.7% a
year, tapering off in the early 20s. At the same time, the brain's white matter
thickens. The white matter is composed of fatty myelin sheaths that encase axons
and, like insulation on a wire, make nerve-signal transmissions faster and more
efficient. With each passing year (maybe even up to age 40) myelin sheaths thicken,
much like tree rings. During adolescence, says Giedd, summing up the process, "you
get fewer but faster connections in the brain." The brain becomes a more efficient
machine, but there is a trade-off: it is probably losing some of its raw potential for
learning and its ability to recover from trauma.
Most scientists believe that the pruning is guided both by genetics and by a use-it-orlose-it
principle. Nobel prizewinning neuroscientist Gerald Edelman has described
that process as "neural Darwinism"--survival of the fittest (or most used) synapses.
How you spend your time may be critical. Research shows, for instance, that
practicing piano quickly thickens neurons in the brain regions that control the
fingers. Studies of London cab drivers, who must memorize all the city's streets,
show that they have an unusually large hippocampus, a structure involved in
memory. Giedd's research suggests that the cerebellum, an area that coordinates
both physical and mental activities, is particularly responsive to experience, but he
warns that it's too soon to know just what drives the buildup and pruning phases.
He's hoping his studies of twins will help answer such questions: "We're looking at
what they eat, how they spend their time--is it video games or sports Now the fun
begins," he says.
No matter how a particular brain turns out, its development proceeds in stages,
generally from back to front. Some of the brain regions that reach maturity earliest--
through proliferation and pruning--are those in the back of the brain that mediate
direct contact with the environment by controlling such sensory functions as vision,
hearing, touch and spatial processing. Next are areas that coordinate those
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functions: the part of the brain that helps you know where the light switch is in your
bathroom even if you can't see it in the middle of the night. The very last part of the
brain to be pruned and shaped to its adult dimensions is the prefrontal cortex, home
of the so-called executive functions--planning, setting priorities, organizing thoughts,
suppressing impulses, weighing the consequences of one's actions. In other words,
the final part of the brain to grow up is the part capable of deciding, I'll finish my
homework and take out the garbage, and then I'll IM my friends about seeing a
movie.
"Scientists and the general public had attributed the bad decisions teens make to
hormonal changes," says Elizabeth Sowell, a UCLA neuroscientist who has done
seminal MRI work on the developing brain. "But once we started mapping where and
when the brain changes were happening, we could say, Aha, the part of the brain
that makes teenagers more responsible is not finished maturing yet."
RAGING HORMONES
Hormones, however, remain an important part of the teen-brain story. Right about
the time the brain switches from proliferating to pruning, the body comes under the
hormonal assault of puberty. (Research suggests that the two events are not closely
linked because brain development proceeds on schedule even when a child
experiences early or late puberty.) For years, psychologists attributed the intense,
combustible emotions and unpredictable behavior of teens to this biochemical
onslaught. And new research adds fresh support. At puberty, the ovaries and testes
begin to pour estrogen and testosterone into the bloodstream, spurring the
development of the reproductive system, causing hair to sprout in the armpits and
groin, wreaking havoc with the skin, and shaping the body to its adult contours. At
the same time, testosterone-like hormones released by the adrenal glands, located
near the kidneys, begin to circulate. Recent discoveries show that these adrenal sex
hormones are extremely active in the brain, attaching to receptors everywhere and
exerting a direct influence on serotonin and other neurochemicals that regulate
mood and excitability.
The sex hormones are especially active in the brain's emotional center--the limbic
system. This creates a "tinderbox of emotions," says Dr. Ronald Dahl, a psychiatrist
at the University of Pittsburgh. Not only do feelings reach a flash point more easily,
but adolescents tend to seek out situations where they can allow their emotions and
passions to run wild. "Adolescents are actively looking for experiences to create
intense feelings," says Dahl. "It's a very important hint that there is some particular
hormone-brain relationship contributing to the appetite for thrills, strong sensations
and excitement." This thrill seeking may have evolved to promote exploration, an
eagerness to leave the nest and seek one's own path and partner. But in a world
where fast cars, illicit drugs, gangs and dangerous liaisons beckon, it also puts the
teenager at risk.
That is especially so because the brain regions that put the brakes on risky,
impulsive behavior are still under construction. "The parts of the brain responsible
for things like sensation seeking are getting turned on in big ways around the time of
puberty," says Temple University psychologist Laurence Steinberg. "But the parts for
exercising judgment are still maturing throughout the course of adolescence. So
you've got this time gap between when things impel kids toward taking risks early in
adolescence, and when things that allow people to think before they act come online.
It's like turning on the engine of a car without a skilled driver at the wheel."
DUMB DECISIONS
Increasingly, psychologists like Steinberg are trying to connect the familiar patterns
of adolescents' wacky behavior to the new findings about their evolving brain
structure. It's not always easy to do. "In all likelihood, the behavior is changing
because the brain is changing," he says. "But that is still a bit of a leap." A critical
tool in making that leap is functional magnetic resonance imaging (fMRI). While
ordinary MRI reveals brain structure, fMRI actually shows brain activity while
subjects are doing assigned tasks.
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What Makes Teens Tick; A flood of hormones, sure. But also a host of struct...plain the behaviors that make adolescence so exciting--and so exasperating
At McLean Hospital in Belmont, Mass., Harvard neuropsychologist Deborah Yurgelun-
Todd did an elegant series of FMRI experiments in which both kids and adults were
asked to identity the emotions displayed in photographs of faces. "In doing these
tasks," she says, "kids and young adolescents rely heavily on the amygdala, a
structure in the temporal lobes associated with emotional and gut reactions. Adults
rely less on the amygdala and more on the frontal lobe, a region associated with
planning and judgment." While adults make few errors in assessing the photos, kids
under 14 tend to make mistakes. In particular, they identify fearful expressions as
angry, confused or sad. By following the same kids year after year, Yurgelun-Todd
has been able to watch their brain-activity pattern--and their judgment--mature.
Fledgling physiology, she believes, may explain why adolescents so frequently
misread emotional signals, seeing anger and hostility where none exists. Teenage
ranting ("That teacher hates me!") can be better understood in this light.
At Temple University, Steinberg has been studying another kind of judgment: risk
assessment. In an experiment using a driving-simulation game, he studies teens and
adults as they decide whether to run a yellow light. Both sets of subjects, he found,
make safe choices when playing alone. But in group play, teenagers start to take
more risks in the presence of their friends, while those over age 20 don't show much
change in their behavior. "With this manipulation," says Steinberg, "we've shown
that age differences in decision making and judgment may appear under conditions
that are emotionally arousing or have high social impact." Most teen crimes, he says,
are committed by kids in packs.
Other researchers are exploring how the adolescent propensity for uninhibited risk
taking propels teens to experiment with drugs and alcohol. Traditionally,
psychologists have attributed this experimentation to peer pressure, teenagers'
attraction to novelty and their roaring interest in loosening sexual inhibitions. But
researchers have raised the possibility that rapid changes in dopamine-rich areas of
the brain may be an additional factor in making teens vulnerable to the stimulating
and addictive effects of drugs and alcohol. Dopamine, the brain chemical involved in
motivation and in reinforcing behavior, is particularly abundant and active in the
teen years.
Why is it so hard to get a teenager off the couch and working on that all important
college essay You might blame it on their immature nucleus accumbens, a region in
the frontal cortex that directs motivation to seek rewards. James Bjork at the
National Institute on Alcohol Abuse and Alcoholism has been using fMRI to study
motivation in a challenging gambling game. He found that teenagers have less
activity in this region than adults do. "If adolescents have a motivational deficit, it
may mean that they are prone to engaging in behaviors that have either a really
high excitement factor or a really low effort factor, or a combination of both." Sound
familiar Bjork believes his work may hold valuable lessons for parents and society.
"When presenting suggestions, anything parents can do to emphasize more
immediate payoffs will be more effective," he says. To persuade a teen to quit
drinking, for example, he suggests stressing something immediate and tangible--the
danger of getting kicked off the football team, say--rather than a future on skid row.
Persuading a teenager to go to bed and get up on a reasonable schedule is another
matter entirely. This kind of decision making has less to do with the frontal lobe than
with the pineal gland at the base of the brain. As nighttime approaches and daylight
recedes, the pineal gland produces melatonin, a chemical that signals the body to
begin shutting down for sleep. Studies by Mary Carskadon at Brown University have
shown that it takes longer for melatonin levels to rise in teenagers than in younger
kids or in adults, regardless of exposure to light or stimulating activities. "The brain's
program for starting nighttime is later," she explains.
PRUNING PROBLEMS
The new discoveries about teenage brain development have prompted all sorts of
questions and theories about the timing of childhood mental illness and cognitive
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disorders. Some scientists now believe that ADHD and Tourette's syndrome, which
typically appear by the time a child reaches age 7, may be related to the brain
proliferation period. Though both disorders have genetic roots, the rapid growth of
brain tissue in early childhood, especially in regions rich in dopamine, "may set the
stage for the increase in motor activities and tics," says Dr. Martin Teicher, director
of developmental biopsychiatry research at McLean Hospital. "When it starts to
prune in adolescence, you often see symptoms recede."
Schizophrenia, on the other hand, makes its appearance at about the time the
prefrontal cortex is getting pruned. "Many people have speculated that schizophrenia
may be due to an abnormality in the pruning process," says Teicher. "Another
hypothesis is that schizophrenia has a much earlier, prenatal origin, but as the brain
prunes, it gets unmasked." MRI studies have shown that while the average teenager
loses about 15% of his cortical gray matter, those who develop schizophrenia lose as
much as 25%.
WHAT'S A PARENT TO DO
Brain scientists tend to be reluctant to make the leap from the laboratory to real-life,
hard-core teenagers. Some feel a little burned by the way earlier neurological
discoveries resulted in Baby Einstein tapes and other marketing schemes that
misapplied their science. It is clear, however, that there are implications in the new
research for parents, educators and lawmakers.
In light of what has been learned, it seems almost arbitrary that our society has
decided that a young American is ready to drive a car at 16, to vote and serve in the
Army at 18 and to drink alcohol at 21. Giedd says the best estimate for when the
brain is truly mature is 25, the age at which you can rent a car. "Avis must have
some pretty sophisticated neuroscientists," he jokes. Now that we have scientific
evidence that the adolescent brain is not quite up to scratch, some legal scholars
and child advocates argue that minors should never be tried as adults and should be
spared the death penalty. Last year, in an official statement that summarized
current research on the adolescent brain, the American Bar Association urged all
state legislatures to ban the death penalty for juveniles. "For social and biological
reasons," it read, "teens have increased difficulty making mature decisions and
understanding the consequences of their actions."
Most parents, of course, know this instinctively. Still, it's useful to learn that teenage
behavior is not just a matter of willful pigheadedness or determination to drive you
crazy--though these, too, can be factors. "There's a debate over how much
conscious control kids have," says Giedd, who has four "teenagers in training" of his
own. "You can tell them to shape up or ship out, but making mistakes is part of how
the brain optimally grows." It might be more useful to help them make up for what
their brain still lacks by providing structure, organizing their time, guiding them
through tough decisions (even when they resist) and applying those time-tested
parental virtues: patience and love.
--With reporting by Alice Park/New York
INSIDE THE ADOLESCENT BRAIN
The brain undergoes two major developmental spurts, one in the womb and the
second from childhood through the teen years, when the organ matures by fits and
starts in a sequence that moves from the back of the brain to the front
BRAIN AREA
DESCRIPTION / DUTIES
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CORPUS CALLOSUM
PREFRONTAL CORTEX
BASAL GANGLIA
AMYGDALA
CEREBELLUM
Thought to be involved in problem
solving and creativity, this bundle
of nerve fibers connects the left
and right hemispheres of the brain.
During adolescence, the nerve
fibers thicken and process
information more and more
efficiently
The CEO of the brain, also called
the area of sober second thought,
is the last part of the brain to
mature-which may be why teens
get into so much trouble. Located
just behind the forehead, the
prefrontal cortex grows during the
preteen years and then shrinks as
neural connections are pruned
during adolescence
Larger in females than in males,
this part of the brain acts like a
secretary to the prefrontal cortex
by helping it prioritize information.
The basal ganglia and prefrontal
cortex are tightly connected: at
nearly the same time, they grow
neuron connections and then prune
them. This area of the brain is also
active in small and large motor
movements, so it may be important
to expose preteens to music and
sports while it is growing
This is the emotional center of the
brain, home to such primal feelings
as fear and rage. In processing
emotional information, teens tend
to rely more heavily on the
amygdala. Adults depend more on
the rational prefrontal cortex, a
part of the brain that is
underdeveloped in teens. That may
explain why adolescents often react
more impulsively than adults
Long thought to play a role in
physical coordination, this area
may also regulate certain thought
processes. More sensitive to
environment than to heredity, the
cerebellum supports activities of
higher learning like mathematics,
music and advanced social skills.
New research shows that it changes
dramatically during adolescence,
increasing the number of neurons
and the complexity of their
connections. The cerebellum is the
only part of the brain that
continues growing well into the
early 20s
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NERVE PROLIFERATION...
By age 11 for girls and 12 1/2 for
boys, the neurons in the front of
the brain have formed thousands of
new connections. Over the next few
years, most of these links will be
pruned
... AND PRUNING Those that are used and reinforcedthe
pathways involved in language,
for example-will be strengthened,
while the ones that aren't used will
die out
Sources: Dr. Jay Giedd, chief of brain imaging, child psychiatry branch, NIMH; Paul
Thompson, Andrew Lee, Kiralee Hayashi and Arthur Toga, UCLA Lab of Neuro
Imaging; Nitin Gogtay and Judy Rapoport, child psychiatry branch, NIMH
Text by Kristina Dell
Home | About DPIC | Privacy Policy
©2006 Death Penalty Information Center
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Teen Brains on Trial: Science News Online, May 8, 2004
Week of May 8, 2004; Vol. 165, No. 19 , p. 299
Teen Brains on Trial
The science of neural development tangles with the juvenile
death penalty
Bruce Bower
Science News
Web
Later this year, the U.S. Supreme Court will hear arguments about whether
federal law should continue to permit executions of 16- and 17-year-olds
convicted of murder. On this life-or-death issue, controversial legal and ethical
views on teenagers' capacity to control their behavior and obey the law will
take center stage. However, a relative newcomer to the debate—the
burgeoning science of brain development—may critically influence the high
court's final decision.
A coalition of psychiatric and legal organizations plans to submit a brief to the
justices contending that teenagers often make poor decisions and act
impulsively because their brains haven't attained an adult level of
organization. Consequently, the coalition argues, teenage killers are less
culpable for their crimes than their adult counterparts are. Capital punishment
of teens thus violates the constitutional amendment protecting citizens from
cruel and unusual punishment.
Science News
for Kids
Subscribe to an
audio format
"Our objection to the juvenile
death penalty is rooted in the fact
that adolescents' brains function
in fundamentally different ways
than adults' brains do," says
David Fassler, a psychiatrist at
the University of Vermont in
Burlington and a leader of the
effort to infuse capital-crime laws
with brain science.
Published by
Age-related brain differences
pack a real-world wallop, in his
view. "From a biological
perspective," Fassler asserts, "an
anxious adolescent with a gun in
a convenience store is more
likely to perceive a threat and pull
the trigger than is an anxious
adult with a gun in the same
store."
MENTAL MATURITY New data on teens'
unfinished brain development may aid efforts to get
rid of the juvenile death penalty in the United States.
PhotoDisk
Fassler and two like-minded colleagues—neuropsychologist Ruben Gur of the
University of Pennsylvania in Philadelphia and lawyer Stephen Harper of the
University of Miami—spoke in March at a Washington, D.C., press conference
convened by groups that included the American Psychiatric Association and
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Teen Brains on Trial: Science News Online, May 8, 2004
the American Bar Association.
Yet the zeal with which these organizations now wield brain studies to fight
the juvenile death penalty masks a deep division among scientists about
whether the data are ready for legal prime time.
Some researchers agree that capital-punishment laws should incorporate
what's known about teenagers' incomplete brain development, even if the
scientific story contains gaps. Don't excuse criminal behavior, these scientists
say, but acknowledge that adolescents who kill don't deserve the ultimate
punishment.
Members of another camp argue that brain science doesn't belong in court
because there's no evidence linking specific characteristics of teens' brains to
any legally relevant condition, such as impaired moral judgment or an inability
to control murderous impulses.
"Juvenile death sentences bother me, but this is an ethical issue," remarks
Harvard University psychologist Jerome Kagan. "The brain data don't show
that adolescents typically have reduced legal culpability for crimes."
Frontal assault
Plans to apply brain science to balance the scales of justice come at a time
when the juvenile death penalty is already on the defensive.
As of January 2004, 29 states prohibited capital punishment of juveniles.
Legislation to bar the death penalty for offenders under 18 years old is being
considered in 14 additional states. Juvenile-death-penalty foes find this trend
encouraging, since the Supreme Court justified its 2002 ruling against
executing mentally retarded offenders by citing bans on that practice in 30
states.
Another heartening sign for opponents of the juvenile death penalty occurred
in December 2003, when a Virginia jury decided to sentence 17-year-old Lee
Malvo to life in prison for his participation in the D.C.-area sniper killings.
However, growing evidence that teenagers possess unfinished brains has
received far more attention in the media than in the courts, Harper says. The
legal system doesn't appreciate that young people's brains aren't fully
equipped for making long-term plans and reining in impulses, he contends.
Much of the concern about teen brains focuses on the frontal lobes. One way
that scientists have learned about frontal lobe activity is by identifying
associations between certain behaviors and increased frontal activity in
healthy people. That work elaborated on previous studies of behavior
changes in individuals who had suffered frontal-brain damage. Together, the
findings implicate this neural region in regulating aggression, long-range
planning, mental flexibility, abstract thinking, the capacity to hold in mind
related pieces of information, and perhaps moral judgment.
Other investigations indicate that the number of brain cells and their
connections surge just before puberty. But through late adolescence, pruning
of excess neurons and their linkages produces substantial declines in the
volume of the part of the brain, called the gray matter, that contains the cell
bodies. Therefore, the brain changes during adolescence mirror the initial
wave of gray matter expansion in the womb and during the first 18 months of
life, followed by a trimming-back period.
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Teen Brains on Trial: Science News Online, May 8, 2004
Using magnetic resonance imaging (MRI) scanners to probe the brains of
healthy teenagers and young adults, Elizabeth R. Sowell of the University of
California, Los Angeles (UCLA) and her colleagues reported in 1999 that
myelin, the fatty tissue around nerve fibers that fosters transmission of
electrical signals, accumulates especially slowly in the frontal lobe.
The late phase of myelin formation, occurring in teenagers, provides a neural
basis for assuming that teens are less blameworthy for criminal acts that
adults are, Gur says. There's no way to say whether, for example, an
individual 17-year-old possesses a fully mature brain. But the biological age of
maturity generally falls around age 21 or 22, in Gur's view.
Although 18 years old represents an arbitrary cutoff age for receiving a capital
sentence, it's preferable to 17, according to Gur.
"These brain data create reasonable doubt that a teenager can be held
culpable for a crime to the same extent that an adult is," agrees neuroscientist
J. Anthony Movshon of New York University.
Fear factor
Abigail A. Baird of Dartmouth College in Hanover, N.H., also suspects that
delayed neural development undermines teens' judgment in ways that affect
their legal standing. "There's no reason to say adulthood happens at age 18,"
Baird says. Unlike Gur, however, she estimates that the brain achieves
maturity at age 25 or 26.
A 1999 investigation led by Baird and Deborah Yurgelun-Todd of Harvard
Medical School in Boston raised the possibility that certain characteristics of
teens' brains make it difficult for them to recognize when other people are
scared. They tested 12 teenagers, ages 12 to 17. A functional magnetic
resonance imaging (fMRI) scanner measured changes throughout
participants' brains in blood flow, which studies have indicated reflect dips and
rises in neural activity. As the teens briefly viewed and identified fear in
pictures of people who had intentionally tried to look scared, the researchers
observed marked increases in activity of an almond-shaped inner-brain
structure called the amygdala.
Neuroscientists suspect that the amygdala is important for learning to attach
emotional significance to facial expressions and other stimuli. However, the
results of Baird and Yurgelun-Todd indicated that there may not be a simple
relationship between amygdala activity and accurate face reading.
The teen volunteers—all with active amygdalas—incorrectly identified one in
four fear expressions, usually labeling them as angry, sad, or confused.
In an ensuing fMRI study directed by Yurgelun-Todd, 16 participants ages 12
to 17 also erred frequently when labeling the emotion on fearful faces. Those
less than 14 years old answered incorrectly about half the time and yet
showed the most amygdala activity, while older teens made fewer errors and
displayed less activity in the amygdala and more in the frontal lobes than the
younger participants did.
Previous studies had found that, when given the same task, adults label most
fearful expressions correctly and exhibit much more activity in the frontal
lobes than in the amygdala.
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Teen Brains on Trial: Science News Online, May 8, 2004
The results in these small experiments remain preliminary. Even if the findings
hold up, it's not clear whether young teens' difficulties in discerning fearful
expressions stem from incomplete brain development or reflect unique duties
assumed by the frontal lobes during adolescence. What's more, teenagers
and adults have yet to be similarly tested with faces displaying emotions other
than fear.
Baird's ongoing research suggests that the teen frontal brain indeed responds
to spontaneous emotional expressions on the faces of friends and family
members. "Kids say that the posed expressions we show them look kind of
weird," Baird says.
Other evidence suggests that mental efficiency in solving emotion-related
tasks—indicated by the time taken to answer them correctly—suffers with the
arrival of puberty, when gray matter volume in the frontal lobes hits its peak,
according to Robert F. McGivern of San Diego State University.
Response speed improves gradually after puberty and stabilizes at around
age 15, a time when substantial neural pruning and myelin expansion in the
frontal lobes have already occurred, McGivern and his colleagues reported in
2002.
The researchers had studied 246 youngsters, ages 10 to 17, and 49 young
adults, ages 18 to 22. In one trial, participants saw a series of faces with
various posed expressions—happy, angry, sad, or neutral—after being told to
answer "yes" if they saw a happy face and "no" for all others. Each face
appeared for only a fraction of a second.
The participants then completed three additional trials in which they were told
to answer "yes" for angry, sad, or neutral faces.
Girls responded to these problems more slowly at ages 11 and 12 than they
did at age 10, while boys took longer to answer at age 12 than they did at
ages 11 or 10. These declines closely corresponded to puberty's onset in
each sex, McGivern says.
Cycles of brain growth in boys and girls, which are timed differently during
adolescence, sometimes aid and sometimes hinder mental dexterity in
detecting various emotions, in McGivern's view.
Risky business
Scientists are also beginning to probe the brain's contributions to teenagers'
penchant for risky and impulsive behaviors, such as experimenting with illicit
drugs. Preliminary data indicate that, while playing a simple game to win
monetary prizes, adolescents exhibit weaker activity than young adults do in a
brain region that scientists consider to be crucial for motivating efforts to
obtain rewards or attain goals.
A team led by James M. Bjork of the National Institute on Alcohol Abuse and
Alcoholism in Bethesda, Md., used fMRI to scan the brains of 24 people, half
between ages 12 and 17 and the rest between 22 and 28. Brain
measurements were taken as the participants decided whether to press a
button upon seeing various visual cues, only one of which they had been told
to respond to. On some trials, correct answers yielded prizes of 20 cents, 1
dollar, or 5 dollars. On others, correct answers prevented losses of those
amounts.
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Teen Brains on Trial: Science News Online, May 8, 2004
The prospect of gaining or losing money elicited many common responses in
the brains of teens and young adults, the scientists reported in the Feb. 25
Journal of Neuroscience. However, on potential moneymaking trials, teens
displayed unusually weak activity in the right ventral striatum, a structure at
the brain's base that's been implicated in fueling the motivation to acquire
rewards.
This finding is consistent with the theory that the amount of stimulation that's
enough to give adults a motivational boost is insufficient to arouse teens. To
get the same rewarding feeling, teens may seek the added lift that comes
from risky behaviors. Bjork and his coworkers plan to conduct larger fMRI
studies of teen motivation that include youngsters prone to delinquency and
drug abuse.
There's still a long way to go in untangling how brain development influences
what teens do and why they do it, remarks Jay N. Giedd of the National
Institute of Mental Health in Bethesda. Courts and legislatures grappling with
the juvenile death penalty nonetheless need to consider the brain's unfinished
status during adolescence, especially in the frontal lobes, according to Giedd,
a pioneer in research on brain development.
Adds neuroscientist Bruce McEwen of Rockefeller University in New York
City, "There's enough known about brain development to call for serious
discussions between scientists and the legal community."
Immature data
UCLA's Elizabeth Sowell, another prominent brain-development researcher,
takes a dim view of the movement to apply neuroscience to the law. Delayed
frontal-lobe maturation may eventually be shown to affect teenagers' capacity
to make long-term plans and control their impulses, she says, but no current
research connects specific brain traits of typical teenagers to any mental or
behavioral problems.
"The scientific data aren't ready to be used by the judicial system," she
remarks. "The hardest thing [for neuroscientists to do] is to bring brain
research into real-life contexts."
The ambiguities of science don't mix with social and political causes, contends
neuroscientist Bradley S. Peterson of the Columbia College of Physicians and
Surgeons in New York City. For instance, it's impossible to say at what age
teenagers become biologically mature because the brain continues to develop
in crucial ways well into adulthood, he argues.
A team led by Sowell and Peterson used an MRI scanner to probe the volume
of white and gray matter throughout the brains of 176 healthy volunteers,
ages 7 to 87. The researchers reported in the March 2003 Nature
Neuroscience that myelin formation—measured by the total volume of white
matter in the entire brain—doesn't reach its peak until around age 45.
Although gray matter volume generally declines beginning around age 7, it
steadily increases until age 30 in a temporal-lobe region associated with
language comprehension.
Such findings underscore the lack of any sharp transition in brain
development that signals maturity, according to neuroscientist William T.
Greenough of the University of Illinois at Urbana-Champaign. Definitions of
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Teen Brains on Trial: Science News Online, May 8, 2004
adulthood change depending on social circumstances, Greenough points out.
Only 200 years ago, Western societies regarded 16-year-olds as adults.
"Brain science offers no simple take-home message about adolescents," says
B.J. Casey of Cornell University's Weill Medical College in New York City. "It's
amazing how little we know about the developing brain."
Brain-scanning techniques, including the popular fMRI, remain a "crude level
of analysis," Casey notes. At best, blood-flow measurements indirectly tap
into brain-cell activity as people perform a task, such as identifying emotions
in posed faces, that may superficially simulate a real-world endeavor. What's
more, many critical brain-cell responses are too fast for MRI to track.
Brain data, particularly those on delayed frontal-lobe growth in adolescents,
also need to be put in a cultural and historical perspective, Harvard's Kagan
asserts. Frontal-lobe development presumably proceeds at roughly the same
pace in teenagers everywhere. Yet current rates of teen violence and murder
vary from remarkably low to alarmingly high from country to country, he notes.
"Something about cultural context must be critical here," Kagan says. "Under
the right conditions, 15-year-olds can control their impulses without having
fully developed frontal lobes."
If incomplete brains automatically reduce adolescents' capacity to restrain
their darker urges, "we should be having Columbine incidents every week," he
adds.
Several research teams have now undertaken the difficult task of searching
for links between specific traits of teens' brains and their real-life decisions
and behaviors, says psychiatrist Ronald Dahl of the University of Pittsburgh
Medical Center. "Brain data are eventually going to support reduced legal
culpability for adolescents," Dahl predicts "but we're not quite there yet."
It remains to be seen where the Supreme Court is.
Letters:
I am not an advocate of capital punishment, but I wonder whether the
people and organizations who are so anxious to use findings on brain
maturity to raise the age of capitol punishment have considered the
consequences of winning their case. One might argue on the same basis
that anyone who has not yet reached the "age of brain maturity" should
not be allowed to make potentially life-altering decisions. Should such
people be permitted to volunteer for the armed services Should they be
denied access to any form of weapon Should they be permitted to
participate in any high-risk sport Should they be allowed to operate cars
and other vehicles if their immature brains could lead them to make bad,
or even lethal, driving decisions Would it not be possible to argue that
such measures would protect society at large
Lance C. Labun
Tempe, Ariz.
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Teen Brains on Trial: Science News Online, May 8, 2004
If you have a comment on this article that you would like considered for
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References:
Baird, A.A., et al. 1999. Functional magnetic resonance imaging of facial
affect recognition in children and adolescents. Journal of the American
Academy of Child and Adolescent Psychiatry 38(February):195.
Bjork, J.M., et al. 2004. Incentive-elicited brain activation in adolescents:
Similarities and differences from young adults. Journal of Neuroscience 24
(Feb. 25):1793-1802. Abstract available at http://www.jneurosci.org/cgi/
content/abstract/24/8/1793.
McGivern, R.F., et al. 2002. Cognitive efficiency on a match to sample
task decreases at the onset of puberty in children. Brain and Cognition
50:73-89.
Sowell, E.R., B.S. Peterson, et al. 2003. Mapping cortical change across
the human life span. Nature Neuroscience 6(March):309-315. Abstract
available at http://dx.doi.org/10.1038/nn1008.
Sources:
Abigail Baird
Department of Psychological and Brain Science
Dartmouth College
6207 Moore Hall
Hanover, NH 03755
James M. Bjork
National Institute on Alcohol Abuse and Alcoholism
National Institutes of Health
10 Center Drive, Room 3C-103
Bethesda, MD 20892
Ronald E. Dahl
Western Psychiatric Institute and Clinic
Department of Psychiatry
Thomas Detre Hall
University of Pittsburgh
3811 O'Hara Street
Pittsburgh, PA 15213
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Teen Brains on Trial: Science News Online, May 8, 2004
David G. Fassler
University of Vermont
Department of Psychiatry
c/o Otter Creek Association
86 Lake Street
Burlington, VT 05401
Jay N. Giedd
Building 10, Room 4C110
National Institutes of Health
National Institute of Mental Health
Magnuson CC
Bethesda, MD 20892
William T. Greenough
University of Illinois, Urbana-Champaign
2325 Beckman Institute
405 N. Matthews Avenue
Urbana, IL 61801
Stephen K. Harper
University of Miami
School of Law
1311 Miller Drive
Coral Gables, FL 33146
Jerome Kagan
Harvard University
Department of Psychology
1514 WM James Hall
Cambridge, MA 02138
Robert F. McGivern
San Diego State University
6330 Alvarado Ct, 207
San Diego, CA 92120
J. Anthony Movshon
New York University
Center for Neural Science
4 Washington Place, Room 809
New York, NY 10003
Bradley S. Peterson
Columbia College of Physicians & Surgeons
Department of Psychiatry
New York State Psychiatric Institute
New York, NY 10032
Elizabeth R. Sowell
University of California, Los Angeles
Laboratory of Neuroimaging
Department of Neurology
710 Westwood Plaza, Room 4-238
Los Angeles, CA 90024-1769
Deborah Yurgelun-Todd
McLean Hospital
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Teen Brains on Trial: Science News Online, May 8, 2004
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From Science News, Vol. 165, No. 19, May 8, 2004, p. 299.
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