Unit 1 - Biological Bases of Behavior

Norepinephrine

A chemical classified as both a hormone and neurotransmitter that assists in the regulation of arousal, attention, cognitive function, and stress reactions.

Glutamate

The predominant excitatory neurotransmitter in the brain. Plays a critical role in cognitive, motor, and sensory functions.

GABA

a major inhibitory neurotransmitter in the nervous system.

Acetylcholine

a major neurotransmitter that plays an important role in memory formation and learning. Is implicated in both Alzheimer's disease and myasthenia gravis.

Limbic System

Neural system located mostly in the forebrain - below the cerebral hemispheres - that includes the amygdala, hypothalamus, hippocampus, thalamus, and pituitary gland; associated with emotions and drives.

Thalamus

The forebrain's sensory control center, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla.

Brain Lateralization

The organization of the brain into right and left hemispheres, with each hemisphere performing unique and specialized functions.

EEG (Electroencephalogram)

An amplified recording of the waves of electrical activity sweeping across the brain's surface. These waves are measured by electrodes placed on the scalp.

fMRI

A technique for revealing blood flow, and therefore, brain activity by comparing successive MRI scans. Show function as well as structure.

MRI (magnetic resonance imaging)

a technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue. Show brain anatomy.

Activation Synthesis Theory

Theory that dreams reflect inputs from brain activation originating in the pons, which the forebrain then attempts to weave into a story

Weber's Law

the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount).

Retina

The light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information.

Fovea

The central focal point in the retina, around which the eye's cones cluster.