Teaching With the Brain in Mind

Glossary
of Brain Terms
115
◗ Acetylcholine. A common neurotransmitter, particularly
involved in long-term memory formation.
Specifically released at neuromuscular junctions, it’s
present at higher levels during rest and sleep. These
junctions are at the terminal between a motor nerve
axon and a skeletal muscle fiber.
◗ ACTH. Also adrenocorticotropin hormone. This
stress-related substance is produced by the pituitary
gland. It’s released into your system when you experience
injury, emotion, pain, infections, or other trauma.
◗ Adrenaline. Under conditions of stress, fear, or
excitement, this hormone is released from your
adrenal gland into your bloodstream. When it reaches
your liver, it stimulates the release of glucose for rapid
energy. Abrupt increases caused by anger can constrict
heart vessels, requiring the heart to pump with higher
pressure. Also known as epinephrine.
◗ Amygdala. Located in the middle of the brain, this
almond-shaped complex of related nuclei is a critical
processor area for senses. Connected to the hippocampus,
it plays a role in emotionally laden memories. It
contains a huge number of opiate receptor sites implicated
in rage, fear, and sexual feelings.
◗ Axons. These are the long fibers extending from
the brain cells (neurons) that carry the output (an electrical
nerve impulse) to other neurons. They can be up
to a meter long. There is just one axon per neuron, but
axons can subdivide to connect with many dendrites.