SLEEP 2011 Abstract Supplement

A. Basic Science XI. Sleep Deprivation
0277
AN fMRI STUDY OF SLEEP DEPRIVATION AND REWARD IN
HEALTHY YOUNG ADULTS
Mullin BC 1 , Phillips ML 1,2 , Siegle GJ 1 , Forbes E 1 , Buysse DJ 1 ,
Franzen PL 1
1
Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh,
PA, USA, 2 Department of Psychological Medicine, Cardiff University,
Cardiff, United Kingdom
Introduction: Sleep loss produces abnormal increases in reward-seeking
behavior, though the neurobiological mechanisms underlying this
phenomenon are poorly understood. We examined the impact of sleep
deprivation upon reward neural circuitry in healthy young adults using
functional Magnetic Resonance Imaging (fMRI) and a well-validated
monetary reward card-guessing paradigm. We also examined associations
between recent sleep history and reward responding when participants
were tested under sleep-deprived and rested conditions.
Methods: Using a within-subjects crossover design, 22 young adults
(age 18-25 years) were tested following a night of total sleep deprivation
and a night of normal sleep. We compared blood oxygen-leveldependent
(BOLD) responses to the winning of monetary reward in a
computer task during sleep-deprived and rested conditions. We used a
region of interest approach focused on the ventral striatum (VS) and
medial prefrontal cortex, areas critical to reward processing. We used
regression analyses to examine relationships between reward response
and total sleep time (TST) derived from actigraphy in the five days preceding
each fMRI scan.
Results: VS activity was significantly greater during reward trials under
sleep-deprived versus rested conditions. TST during the preceding
five days was positively associated with activity in the anterior cingulate
cortex (ACC) during reward trials, both under rested and sleep-deprived
conditions. Thus, lower TST prior to either testing session was associated
with less ACC activation to reward.
Conclusion: Our findings support the hypothesis that sleep loss produces
aberrant functioning in reward neural circuitry, resulting in over-valuation
of positively-reinforcing stimuli. Naturalistic variation in sleep
duration was linked to frontal hypoactivation during the processing of
reward. Such processes could lead to impaired decision-making and abnormally
increased pursuit of reinforcers, which could plausibly lead to
negative health and behavioral consequences.
Support (If Any): This project was supported by NHLBI T32 HL082610
awarded to BCM, and K01 MH077106 awarded to PLF.
0278
SLEEP DEPRIVATION INCREASES AMYGDALA
REACTIVITY DURING EFFORTFUL ATTEMPTS AT
EMOTION REGULATION VIA COGNITIVE REAPPRAISAL
Franzen PL 1 , Buysse DJ 1 , Dahl R 2 , Siegle GJ 1
1
Department of Psychiatry, University of Pittsburgh School of
Medicine, Pittsburgh, PA, USA, 2 School of Public Health, University
of California Berkeley, Berkeley, CA, USA
Introduction: Although sleep loss is known to affect overt emotion,
little is known about how sleep deprivation impairs emotion regulatory
processes and their underlying neural circuitry. We therefore examined
an explicit emotion regulation task using functional MRI (fMRI) following
sleep deprived and rested conditions. We hypothesized that impaired
emotion regulation following sleep deprivation would be associated
with heightened amygdala activity—an area critically involved in the
processing and generation of emotion—when attempting to down-regulate
emotional responses via cognitive reappraisal.
Methods: Using a within-subjects crossover design, 26 healthy participants
(18-25 years old) underwent fMRI scanning in the morning
following a night of normal sleep and following a night of sleep deprivation.
Prior to the first fMRI scan, participants were trained in specific
reappraisal strategies (i.e., instructions to decrease one’s emotional
response by reinterpreting pictures; e.g., when viewing a person who
appears hurt, thinking that help is on the way or that the person is not in
as much pain as it seems). Participants viewed International Affective
Picture System stimuli with either neutral or negative content for 7-seconds.
For negative pictures, participants were instructed to either simply
view or down-regulate (e.g., via reappraisal) their emotional responses.
Results: A significant trial type by sleep condition interaction was detected
in the right amygdala, F=2.02, voxelwise p=0.018, 7 voxels contiguity,
small volume corrected p