Teaching With the Brain in Mind

Teaching with the Brain in Mind
Axons often build up a fatty white insulation called
myelin.
◗ Basal ganglia. Clusters of nuclei deep within the
cerebrum and the upper parts of the brain stem that
play an important part in producing smooth, continuous
muscular actions in stopping and starting movement.
◗ Brain stem. Located at the top of the spinal cord, it
links the lower brain with the middle of the brain and
cerebral hemispheres. Often referred to as the lower
brain.
◗ Broca’s area. This is part of the left frontal area in
the cerebrum. It converts thoughts into sounds (or
written words) and sends the message to the motor
area. Impulses go first to Wernicke’s area, then to
Broca’s area.
◗ Cerebellum. A cauliflower-shaped structure
located below the occipital area and next to the brain
stem. The word is Latin for “little brain.” Traditionally,
research linked it to balance, posture, coordination,
and muscle movements. Newer research has linked it
to cognition, novelty, and emotions.
◗ Cerebral cortex. This is the newspaper-sized,
1/4-inch thick, outermost layer of the cerebrum. It’s
wrinkled, six layers deep, and packed with brain cells
(neurons). Cortex is the Latin word for “bark” or
“rind.”
◗ Cerebrum. This is the largest part of the brain,
composed of the left and right hemisphere. It has
frontal, parietal, temporal, and occipital lobes.
◗ Cingulate gyrus. This structure lies directly above
the corpus callosum. It mediates communication
between the cortex and mid-brain structures.
◗ Corpus callosum. A white-matter bundle of
200–300 million nerve fibers that connect the left and
right hemispheres. Located in the mid-brain area, it’s
about four inches long.
◗ CORT. Corticotropin is a steroid hormone released
by the adrenal cortex during stress. It binds to a spe-
116
cialized neuronal receptor where regions in the amygdala
and hippocampus are particularly impacted.
◗ CRF. Corticotropin release factor. A chemical
secreted by the hypothalamus that prompts the pituitary
gland to release a stress hormone, ACTH.
◗ Dendrites. These are the strand-like fibers emanating
from the neuron. Similar to spider webs or cracks
in a wall, they are the receptor sites for axons. Each
cell usually has many, many dendrites.
◗ Dentate nucleus. A small structure in the cerebellum.
Responsible for processing signals to other areas
of the brain.
◗ Dopamine. A powerful and common neurotransmitter,
primarily involved in producing positive moods
or feelings. Secreted by neurons in the substantia nigra,
mid-brain, and hypothalamus, it plays a role in movements,
too. It’s commonly in shortage in patients suffering
from Parkinson’s disease.
◗ Endorphin. A natural opiate, this neurotransmitter
is similar to morphine. It is produced in the pituitary
gland. Protects against excessive pain and is released
with ACTH and enkephalins into the brain.
◗ Enkephalin. This morphine-like substance consists
of five opiate-type amino acids. Released into the
brain with ACTH and endorphins to combat pain.
◗ Fornix. A circular arrangement of fibers connecting
the hippocampus to the hypothalamus.
◗ Frontal lobes. One of four main areas of the cerebrum,
the upper brain area. Controls voluntary movement,
verbal expression, problem solving, willpower,
and planning. The other three areas of the cerebrum
are the occipital, parietal, and temporal.
◗ GABA. Shorthand for gamma-aminobutyric acid.
This common neurotransmitter acts as an inhibitory
agent, an “off ” switch. Neurons are constantly “chattering”
with random firing, and GABA prevents the electrical
impulse from moving down the axon.