BIOLOGICAL BASES OF BEHAVIOR Flashcards
Absolute refractory period
The period during which a neuron lies dormant after an action potential has been completed.
Acetylcholine
A neurotransmitter involved in muscle movement, attention, arousal, memory, and emotion.
Action potential
A short-lived change in electric charge inside a neuron.
Adrenal cortex
The outer part of the adrenal glands, which secretes corticosteroids.
Adrenal medulla
inner part of the adrenal glands, which secretes catecholamines.
Adrenocorticotropic hormone (ACTH)
A hormone released by the pituitary gland that stimulates release of corticosteroids from the adrenal cortex.
Afferent nerves
Bundles of axons that carry information from muscles and sense organs to the central nervous system.
Agonists
Chemicals that mimic the action of a particular neurotransmitter.
All-or-none law
States that neurons fire to generate an action potential only if stimulation reaches a minimum threshold.
Amygdala
A part of the limbic system of the brain that is involved in regulating aggression and emotions, particularly fear.
Antagonists
Chemicals that block the action of a particular neurotransmitter.
Atherosclerosis
Hardening of arteries because of cholesterol deposits.
Autonomic nervous system
The part of the peripheral nervous system connected to the heart, blood vessels, glands, and smooth muscles.
Axon
A long thin fiber that transmits signals away from the soma of the presynaptic neuron to other postsynaptic neurons, or to muscles or glands.
Blood-brain barrier
A membrane that lets some substances from the blood into the brain but keeps out others.
Brain
The main organ in the nervous system.
Broca’s area
A part of the brain, in the left frontal lobe, that is involved in speech production.
Catecholamines
Hormones released by the adrenal medulla in response to stress.
Central nervous system
The part of the nervous system that includes the brain and the spinal cord.
Cerebellum
A part of the hindbrain that controls balance and coordination of movement.
Cerebrospinal fluid
The fluid that cushions and nourishes the brain.
Cerebrum
The largest part of the brain, involved in abstract thought and learning.
Chromosomes
Thin strands of DNA that contain genes.
Computerized tomography (CT)
A method for studying the brain that involves taking x-rays of the brain from different angles.