AP Psych Unit 2

biological psychology

the scientific study of the links between biological and psychological processes.

Neuron

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

Dendrites

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

Axon

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

myelin sheath

a fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed as neural impulses hop from one node to the next

action potential

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

refractory period

a period of inactivity after a neuron has fired

threshold

the level of stimulation required to trigger a neural impulse

all-or-none response

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

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

Reuptake

a neurotransmitter's reabsorption by the sending neuron

Acetylcholine

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

Dopamine

A neurotransmitter associated with movement, attention and learning, and emotion

Serotonin

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

Norepinephrine

A neurotransmitter involved in alertness, as well as in learning and mood regulation

GABA

An inhibitory neurotransmitter in the brain.

Glutamate

A major excitatory neurotransmitter; involved in memory

Endorphins

"morphine within"—natural, opiate-like neurotransmitters linked to pain control and to pleasure.

Agonist

a molecule that, by binding to a receptor site, stimulates a response

Antagonist

a molecule that, by binding to a receptor site, inhibits or blocks a response

nervous system

the body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems

central nervous system

the brain and spinal cord

peripheral nervous system

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

Nerves

bundled axons that form neural "cables" connecting the central nervous system with muscles, glands, and sense organs

afferent neurons

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

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

parasympathetic nervous system

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

Homeostasis

A tendency to maintain a balanced or constant internal state; the regulation of any aspect of body chemistry, such as blood glucose, around a particular level

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).

reflex

a simple, automatic response to a sensory stimulus, such as the knee-jerk response

endocrine system

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

Hormones

Chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another

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.

pituitary gland

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

lesion

tissue destruction. In the brain, it can be naturally or experimentally caused destruction of brain tissue

Electroencephalogram (EEG)

Graphical record of brain-wave activity obtained through electrodes placed on the scalp and forehead

CT scan

a series of x-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body

PET scan (positron emission tomography)

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

MRI (magnetic resonance imaging)

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

fMRI (functional MRI)

A technique for revealing bloodflow and, therefore, brain activity by comparing successive MRI scans.

Brainstem

The oldest part and central core of the brain, responsible for automatic survival functions.

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

reticular formation

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

limbic system

neural system located below the cerebral hemispheres; associated with emotions and drives

Cerebellum

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

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

cerebral cortex

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

glial cells

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

frontal lobe

portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgements

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

portion of the cerebral cortex lying at the back of the head; includes areas that receive information from the visual fields

temporal lobe

portion of the cerebral cortex lying roughly above the ears; includes the auditory areas, each receiving information primarily from the opposite ear

motor cortex

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

somatosensory cortex

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

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

Plasticity

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

neurogenesis

the formation of new neurons

corpus callosum

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

split brain

a condition resulting from surgery that isolates the brain's two hemispheres by cutting the fibers (mainly those of the corpus callosum) connecting them

consciousness

our awareness of ourselves and our environment

dual processing

principle that info is often simultaneously processed on separate conscious and unconscious tracks

behavior genetics

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

environment

every nongenetic influence, from prenatal nutrition to the people and things around us

Chromosomes

threadlike structures made of DNA molecules that contain the genes

DNA

A complex molecule containing the genetic information that makes up the chromosomes.

Genes

the biochemical units of heredity that make up the chromosomes; segments of DNA capable of synthesizing proteins

Genome

the complete instructions for making an organism, consisting of all the genetic material in that organism's chromosomes

monozygotic twins

identical twins formed when one zygote splits into two separate masses of cells, each of which develops into a separate embryo

dizygotic twins

often called fraternal twins, occurring when two eggs each get fertilized by two different sperm, resulting in two zygotes in the uterus at the same time

molecular genetics

the subfield of biology that studies the molecular structure and function of genes

Heritability

The proportion of variation among individuals that we can attribute to genes. May vary, depending on the range of populations and environments studied.

interaction

the interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity)

Epigenetics

the study of environmental influences on gene expression that occur without a DNA change

natural selection

the principle that, among the range of inherited trait variations, those contributing to reproduction and survival will most likely be passed on to succeeding generations

Mutation

a random error in gene replication that leads to a change

Hypnosis

a social interaction in which one person suggests to another that certain perceptions, feelings, thoughts, or behaviors will spontaneously occur

posthypnotic suggestion

a suggestion, made during a hypnosis session, to be carried out after the subject is no longer hypnotized; used by some clinicians to help control undesired symptoms and behaviors

Dissociation

a split in consciousness, which allows some thoughts and behaviors to occur simultaneously with others

circadian rhythm

the biological clock; regular bodily rhythms that occur on a 24-hour cycle

REM sleep

Rapid eye movement sleep, a recurring sleep stage during which vivid dreams commonly occur. Also known as paradoxical sleep, because the muscles are relaxed (except for minor twitches) but other body systems are active.

alpha waves

the relatively slow brain waves of a relaxed, awake state

sleep

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

Hallucinations

false sensory experiences, such as seeing something in the absence of an external visual stimulus

delta waves

the large, slow brain waves associated with deep sleep

NREM sleep

non-rapid eye movement sleep; encompasses all sleep stages except for REM sleep

suprachiasmatic nucleus

a pair of cell clusters in the hypothalamus that controls circadian rhythm.

insomnia

recurring problems in falling or staying asleep

Narcolepsy

A sleep disorder characterized by uncontrollable sleep attacks. The sufferer may lapse directly into REM sleep, often at inopportune times.

sleep apnea

a sleep disorder characterized by temporary cessations of breathing during sleep and repeated momentary awakenings

night terrors

a sleep disorder characterized by high arousal and an appearance of being terrified; occur during Stage 4 sleep (unlike nightmares), within two or three hours of falling asleep, and are seldom remembered

dream

a sequence of images, emotions, and thoughts passing through a sleeping person's mind.

manifest content

according to Freud, the remembered story line of a dream

latent content

according to Freud, the underlying meaning of a dream

REM rebound

the tendency for REM sleep to increase following REM sleep deprivation (created by repeated awakenings during REM sleep)

substance use disorder

continued substance craving and use despite significant life disruption and/or physical risk