Glossary 4

Question 1

Serotonin

Answer 1

A monoamine neurotransmitter believed to play many roles, including but not limited to temperature regulation, sensory perception, and the onset of sleep. Neurons using serotonin as a transmitter are found in the brain and gut. Several antidepressant drugs are targeted to brain serotonin systems.

Question 2

Short-Term Memory

Answer 2

A phase of memory in which a limited amount of information may be held for several seconds or minutes.

Question 3

Somatosensory Cortex

Answer 3

A region of the parietal lobe responsible for processing touch and pain signals from the body.

Question 4

Spinal Cord

Answer 4

A bundle of nerve fibers run¬ning through the vertebral column that pri¬marily functions to facilitate communication between the brain and the rest of the body.

Question 5

Stem Cells

Answer 5

Unspecialized cells that renew themselves for long periods through cell division.

Question 6

Stress

Answer 6

Any external stimulus that threatens homeostasis. Many kinds of stress have a negative effect on the body, but some kinds can be helpful.

Question 7

Striatum

Answer 7

A cluster of neurons deep within the brain divided into ventral and dorsal regions. The ventral striatum consists of the nucleus accumbens and the olfactory tubercle, while the dorsal striatum consists of the caudate and putamen. The striatum is a part of the basal ganglia and is involved in reward processing.

Question 8

Stroke

Answer 8

A block in the brain’s blood supply. A stroke can be caused by the rupture of a blood vessel, a clot, or pressure on a blood vessel (as may be caused by a tumor). Without oxygen, neurons in the affected area die, and the part of the body controlled by those cells cannot function. A stroke can result in loss of consciousness and death.

Question 9

Substantia Nigra

Answer 9

A region of the midbrain involved in movement and reward. Parkinson’s disease destroys the dopamine-producing neurons in this region.

Question 10

Suprachiasmatic Nucleus (SCN)

Answer 10

A small group of nerve cells in the hypothalamus that express clock proteins, which go through a biochemical cycle of about 24 hours. This sets the pace for daily cycles of activity, sleep, hormone release, and other bodily functions.

Question 11

Sympathetic Branch

Answer 11

A branch of the autonomic nervous system responsible for mobilizing the body’s energy and resources during times of stress and arousal.

Question 12

Synapse

Answer 12

A physical gap between two neu¬rons that functions as the site of information transfer from one neuron to another.

Question 13

Synaptic Plasticity

Answer 13

The ability of synapses to alter their strength by changing their size, shape, number of receptors, and amount of neurotransmitter released.

Question 14

Synaptic Pruning

Answer 14

The elimination of weak or non-functioning synapses to fine-tune neural circuitry.

Question 15

Taste Buds

Answer 15

A sensory organ found on the tongue.

Question 16

Temporal Lobes

Answer 16

One of the four major subdivisions of each hemisphere of the cerebral cortex. The temporal lobe functions in auditory perception, speech, and complex visual perceptions.

Question 17

Testosterone

Answer 17

A sex hormone produced pri¬marily in the testes but also in lower amounts in the adrenal cortex and ovaries.

Question 18

Thalamus

Answer 18

A structure consisting of two egg-shaped masses of nerve tissue, each about the size of a walnut, deep within the brain. The key relay station for sensory information flowing into the brain, the thalamus filters out information of particular importance from the mass of signals entering the brain.

Question 19

Trophic Factors

Answer 19

Small proteins in the nervous system that are necessary for the de¬velopment, function, and survival of specific groups of neurons.

Question 20

Vagus Nerve

Answer 20

The tenth cranial nerve, it transmits signals from the brain to the heart, lungs, and digestive tract.

Question 21

Voluntary Movement

Answer 21

A motor action that is consciously planned and executed.

Question 22

Wernicke’s Area

Answer 22

A region in the temporal lobe responsible for comprehension of language.
White Matter The part of the brain that contains myelinated nerve fibers. The white matter gets its color from myelin, the insula¬tion covering nerve fibers.

Question 23

Working Memory

Answer 23

A temporary type of declarative memory, the ability to keep a piece of information “in mind.” It is limited to a small amount of data and, unless trans¬ferred to long-term memory, decays within a few seconds.