Unit 1: Biological Bases of Behavior

Physiological Psychology

Examines the influence of genetic factors on behavior and the role of the brain, nervous system, endocrine system, and bodily chemicals in the regulation of behavior.

Huntington's chorea

A rare genetic disease in which the central nervous system degenerates and the individual loses control over voluntary movements, with the symptoms often appearing between ages 30 and 50.

Central Nervous System (CNS)

includes the brain and spinal cord

Peripherial Nervous System (PNS)

the sensory and motor neurons that connect the central nervous system to the rest of the body

sensory (afferent) neurons

neurons that carry incoming information from the sensory receptors to the brain and spinal cord

motor (efferent) neurons

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands

Interneurons

neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs

somatic nervous system

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

autonomic nervous system

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). Its sympathetic division arouses; its parasympathetic division calms.

sympathetic nervous system

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

parasympathetic nervous system

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

nerves

neural "cables" containing many axons. These bundled axons, which are part of the peripheral nervous system, connect the central nervous system with muscles, glands, and sense organs

neurons

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

soma

the cell body of the neuron responsible for maintaining the life of the cell

dendrites

a neuron's bushy, branching extensions that receive messages and conduct impulses toward the cell body

axon

the extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands

myelin sheath

covers the axon of some neurons and helps speed neural impulses

Nodes of Ranvier

gaps in the myelin sheath

terminal buttons

knoblike structures that branch out from an axon

synapse

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

Neurotransmitters

chemical messengers that cross the synaptic gaps between neurons

glial cells

cells in the nervous system that support, nourish, and protect neurons

nerve impulse (action potential)

an electrical signal that conveys information along a neuron

Excitory

promote action potential, causes depolarization

inhibitory

Keeps next cell from firing

Acetylcholine

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

Serotonin

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

Dopamine

influences movement, learning, attention, and emotion

GABA

An inhibitory neurotransmitter in the brain.

glutamate

The most common neurotransmitter in the brain. Excitatory.

Norepinephrine

helps control alertness and arousal

Endorphins

"morphine within"--natural, opiatelike neurotransmitters linked to pain control and to pleasure.

substance P

a neurotransmitter involved in pain perception

pituitary gland

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

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.

Epinephrine (adrenaline)

secreted in response to fear or physical injury

Oxytocin

a key hormone in the reproductive systems of both males and females. It increases contractions during labor and delivery, and it's responsible for the release of breast milk after birth

Agonist

a molecule that increases a neurotransmitter's action

Antagonist psychology

a chemical or drug that binds to receptors in the brain and prevents an agonist from having a reaction

Barbiturates

drugs that depress the activity of the central nervous system, reducing anxiety but impairing memory and judgment

Tranquilizers

Depressant drugs that reduce anxiety and induce relaxation

dependence

the condition that results when the brain develops a chemical need for a drug and cannot function normally without it

Hindbrain

medulla, pons, cerebellum

cerebellum

the "little brain" at the rear of the brainstem; functions include processing sensory input and coordinating movement output and balance

brain stem

midbrain, pons, medulla oblongata

medulla oblongata

Part of the brainstem that controls vital life-sustaining functions such as heartbeat, breathing, blood pressure, and digestion.

Reticular Activating System (RAS)

brain area that plays a key role in arousal

Pons

A brain structure that relays information from the cerebellum to the rest of the brain, such as sleep and arousal

Forebrain

largest part of the brain, containing the cerebral cortex, the thalamus, and the limbic system, among other structures

limbic system

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

Thalamus

the brain'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

Hippocampus

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

anterograde amnesia

an inability to form new memories

Amygdala

two lima bean-sized neural clusters in the limbic system; linked to emotion.

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

lateral hypothalamus

The part of the hypothalamus that produces hunger signals

Ventromedical hypothalamus (VMH)

a brain region that depresses hunger when activated

cerebral cortex

the intricate fabric of interconnected neural cells that covers the cerebral hemispheres; the body's ultimate control and information-processing center

sensory cortex

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

motor cortex

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

corpus callosum

the large band of neural fibers connecting the two brain hemispheres and carrying messages between them

Expressive aphasia (Broca's)

The inability to produce language ( despite being able to understand language)

Receptive aphasia (Wernicke's)

inability to understand spoken or written words

split brain patients

people whose corpus callosum has been surgically severed

contralateral processing

Process in which the right brain processes information from the left visual field and vice versa

cortex components

frontal lobe, parietal lobe, temporal lobe, occipital lobe

frontal lobe

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

parietal lobe

receives sensory input for touch and body position

temporal lobe

A region of the cerebral cortex responsible for hearing and language.

occipital lobe

A region of the cerebral cortex that processes visual information

optic chiasm

point at which optic nerve fibers cross in the brain

association areas

areas of the cerebral cortex that are composed of neurons that help provide sense and meaning to information registered in the cortex

apraxia

impaired ability to carry out motor activities despite intact motor function

agnosia

the inability to recognize familiar objects.

alexia

inability to read

agraphia

inability to write

EEG (electroencephalogram)

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

CAT (computerized axial tomography) scan

scan that shows images as detailed slices of a body part or organ

MRI (magnetic resonance imaging)

is a brain imaging technique that detects magnetic changes in the brain's blood flow patterns.

fMRI (functional MRI)

A technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans. fMRI scans show brain function.

PET (positron emission tomography) scan

a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task

mental reality

a mindset that we create to adapt to the world

Preconscious

Information that is not conscious but is retrievable into conscious awareness

controlled processing

a detailed consideration of evidence and information relying on facts, figures, and logic

automatic processing

encoding of informational details like time, space, frequency, and the meaning of words

sleep

periodic, natural loss of consciousness (as distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation)

delusions

false beliefs

pineal gland

secretes melatonin

beta waves

smaller and faster brain waves, typically indicating mental activity

alpha waves

brain waves that indicate a state of relaxation or light sleep

theta waves

brain waves indicating the early stages of sleep

sleep spindles

short bursts of brain waves detected in stage 2 sleep

K complexes (stage 2)

small groups of larger amplitude waves

delta waves

long, slow waves that indicate the deepest stage of sleep

paradoxical sleep

The type of sleep encountered during REM when internally, the brain and body are active; while externally, the body appears calm and inactive

hypnagogic sensations

life-like hallucinations that occur shortly after falling asleep; usually sensation of falling or floating

REM rebound

increased amounts of REM sleep after being deprived of REM sleep on earlier nights

problem solving theory of dreaming

holds that dreams provide a chance for the mind to work out issues that occupy its attention during waking hours

activation-synthesis theory of dreaming

dreaming occurs when the cerebral cortex synthesizes neural signals generated from activity in the lower part of the brain

Dyssomnias

sleep disorders characterized by insomnia or excessive sleepiness