Modules 4 and 5 - Biological Bases of Behavior

biological psychology

the scientific study of the links between biological and psychological processes

action potential

a neural impulse; a brief electrical charge that travels down an axon

resting potential

the state of the neuron when not firing a neural impulse

all-or-none response

a neuron's reaction of either firing (with a full-strength response) or not firing.

Neurotransmitters

chemical messengers that cross the synaptic gaps between neurons

Acetylcholine

A neurotransmitter that enables learning and memory and also triggers muscle contraction

Dopamine

A neurotransmitter associated with movement, attention and learning and the brain's pleasure and reward system.

Serotonin

A neurotransmitter that affects hunger,sleep, arousal, and mood.

Endorphins

natural, opiate-like neurotransmitters linked to pain control and to pleasure

Central Nervous System (CNS)

consists of the brain and spinal cord

somatic nervous system

the division of the peripheral nervous system that controls the body's skeletal muscles

sympathetic nervous system

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations

Hormones

Chemicals produced by your glands that regulate the activities of different body cells

frontal lobe

associated with reasoning, planning, parts of speech, movement, emotions, and problem solving

parietal lobe

portion of the cerebral cortex lying at the top of the head and toward the rear; receives sensory input for touch and body position

occipital lobe

A region of the cerebral cortex that processes visual information

temporal lobe

An area on each hemisphere of the cerebral cortex near the temples that is the primary receiving area for auditory information

brain stem

Connects the brain and spinal cord

cerebral cortex

outer region of the cerebrum, containing sheets of nerve cells; gray matter of the brain

corpus callosum

A thick band of axons that connects the two cerebral hemispheres and acts as a communication link between them.

Retiular Formation

a nerve network in the brainstem that plays an important role in controlling arousal

Cerebellum

A large structure of the hindbrain that controls fine motor skills.

Amygdala

A limbic system structure involved in memory and emotion, particularly fear and aggression.

motor cortex

an area at the rear of the frontal lobes that controls voluntary movements

association areas

areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather, they are involved in higher mental functions such as learning, remembering, thinking, and speaking

Broca's area

controls language expression - an area, usually in the left frontal lobe, that directs the muscle movements involved in speech.

Plasticity

the brain's ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience

Pons

sleep and arousal

Neuron

a nerve cell; the basic building block of the nervous system

Soma

cell body

Dendrites

Branchlike parts of a neuron that are specialized to receive information.

Nucleus

A part of the cell containing DNA and RNA and responsible for growth and reproduction

Axon

the neuron extension that passes messages through its branches to other neurons or to muscles or glands

myelin sheath

A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.

Schwann cells

Type of glia in the PNS, Supporting cells of the peripheral nervous system responsible for the formation of myelin.

Nodes of Ranvier

a gap in the myelin sheath of a nerve, between adjacent Schwann cells.

axon terminal

The endpoint of a neuron where neurotransmitters are stored

Synapse

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron

threshold

the level of stimulation required to trigger a neural impulse

Agonist

A chemical that mimics the action of a neurotransmitter or blocks the reuptake, maximizing the effects.

Antagonist

chemical that binds to and blocks receptor sites, minimizing the effects of neurotransmitters

Reuptake

a neurotransmitter's reabsorption by the sending neuron

Peripheral Nervous System (PNS)

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.

autonomic nervous system (ANS)

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart)

parasympathetic nervous system

the division of the autonomic nervous system that calms the body, conserving its energy

endocrine system

the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream

pituitary gland

The endocrine system's most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands.

pineal gland

secretes melatonin

thyroid gland

produces hormones that regulate metabolism, body heat, and bone growth

Thymus

An immune organ located near the heart. THe thymus is the site of T cell maturation and is larger in children and adolescents.

adrenal glands

a pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress.

Pancreas

Regulates the level of sugar in the blood

Testes

male gonads

Ovaries

Glands that produce the egg cells and hormones

left hemisphere of brain

controls right side of the body and is logical, contains mathematics, lauguage, & speech

right hemisphere of brain

controls left side of the body and contains creativity and the arts

Electroencephalogram (EEG)

record of the electrical activity of the brain

magnetic resonance imaging (MRI)

brain-imaging method using radio waves and magnetic fields of the body to produce detailed images of the brain

Positron Emission Tomography (PET)

a method of brain imaging that assesses metabolic activity by using a radioactive substance injected into the bloodstream

Phineas Gage

railroad worker who survived a severe brain injury that dramatically changed his personality and behavior; case played a role in the development of the understanding of the localization of brain function

Medulla

the base of the brainstem; controls heartbeat and breathing

Thalamus

the brain's sensory switchboard, 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

limbic system

neural system (including the hippocampus, amygdala, and hypothalamus) located below the cerebral hemispheres; associated with emotions and drives.

Hypothalamus

a neural structure lying below the thalamus; directs eating, drinking, body temperature; helps govern the endocrine system via the pituitary gland, and is linked to emotion

sensory cortex

area at the front of the parietal lobes that registers and processes body touch and movement sensations

aphasia

impairment of language, usually caused by left hemisphere damage either to Broca's area (impairing speaking) or to Wernicke's area (impairing understanding).

Wernicke's area

controls language comprehension

split brain patients

people whose corpus callosum has been surgically severed

Hippocampus

A neural center located in the limbic system that helps process explicit memories for storage.

behavior genetics

the study of the relative power and limits of genetic and environmental influences on behavior

Heritability

The proportion of variation among individuals that we can attribute to genes.

monozygotic (MZ) twins

Twins who originate from one zygote that splits apart very early in development. (Also called identical twins.)

dizygotic (DZ) twins

twins that derive from two zygotes; fraternal twins

evolutionary psychology

the attempt to explain social behavior in terms of genetic factors that have evolved over time according to the principles of natural selection