APPENDIX A

Glossary

Action potential

The term for the electrical signal in a neuron

Afferent nerve cells

Cells that process incoming information

Amygdala

A subcortical structure involved in emotion and emotionally charged memories

Anterior

Toward the front

Apraxia

A dysfunction of movement to command

Aphasia

A dysfunction of language

Association cortex

Cortical area that receives input from a primary sensory cortex and other areas

Autonomic nervous system

The division of the peripheral nervous system controlling involuntary functions

Axon

The portion of the neuron that sends a signal

Basal ganglia

Several subcortical structures involved in movement

Cerebellum

The structure of the posterior portion of the brain involved in movement

Central nervous system (CNS)

The brain and spinal cord

Corpus callosum

The major commissure, or tract, that connects the left and right hemispheres of the brain

Cortex

The covering of the brain

Cranial nerves

Twelve sets of nerves that do not pass through the spinal cord. These nerves are involved in basic functions.

Dementia

A deterioration of intellectual skills

Efferent nerve cells

Nerve cells that send information out of the CNS

Executive functions

Planning, executing, and inhibiting actions

Dendrite

The portion of the neuron that receives information

Dorsal

The back side

Frontal lobe

The most anterior lobe of the brain, involved in decision making and multiple functions

Glial cells

Cells in the CNS that perform a number of maintenance and support functions

Gyrus

A wrinkle in the brain tissue

Hippocampus

A subcortical brain structure involved in developing new memories

Homeostasis

An acceptable range for various bodily states and functions

Hormones

Chemicals released from glands into the circulatory system to affect behavior

Hypothalamus

The subcortical structure involved in regulating the pituitary gland

Inferior

Below

Lateral

On the side

Lateralization

Describes the situation where the neurons on one side of the brain control the functions on the opposite body side

Limbic system

A system of structures in the brain involved in memory and emotion

Medial

Toward the middle or inner portion

Meninges

Three layers of brain covering: the pia mater, arachnoid, and dura mater

Myelin

The fatty sheath covering the axon that facilitates neural transmission

Neurons

The nerve cells in the CNS

Neurotransmitters

The chemicals that are used in neural communication in the CNS

Occipital lobe

The lobe at the posterior portion of the brain, primarily involved in vision

Parasympathetic nervous system

A division of the autonomic nervous system that is involved in slowing down involuntary processes

Parietal lobe

The lobe of the brain involved in touch and spatial information

Perception

The process of interpreting sensory information

Peripheral nervous system

Any nervous tissue outside of the CNS

Pituitary gland

The master gland in the body

Sensation

The detection of physical energy and the environment

Sulcus

An indentation in the brain

Superior

Above

Sympathetic nervous system

A division of the autonomic nervous system that speeds up involuntary processes

Synapse

The space between neurons where neurotransmitters are released

Thalamus

The subcortical structure that acts as a relay station for all sensory information

Transduction

The process of converting physical energy into neural signals

Ventral

The belly side

Ventricles

The spaces in the brain and spinal cord filled with cerebral spinal fluid

Working memory

Analogous to short-term memory. The combination of attention and memory where information is manipulated for very short periods.