AP Psychology - Unit 2

DNA

a long, complex molecule that encodes genetic characteristics

gene

segment of a chromosome that encodes the directions for the inherited physical and mental characteristics of an organism; the functional units of chromosomes

neuron

cell specialized to receive and transmit information to other cells in the body; also called nerve cell

nerves

bundles of many neurons

sensory neuron

nerve cell that carries messages from sense receptors toward the central nervous system; also called an afferent neuron

motor neuron

nerve cell that carries messages away from the central nervous system toward the muscles and glands; also called an efferent neuron

interneuron

a nerve cell that relays messages between nerve cells, especially in the brain and the spinal cord

dendrite

a branched fiber that extends outward from the main cell body and carries information into the neuron

soma

the part of a cell (such as a neuron) containing the nucleus, which includes the chromosomes; also called the cell body

axon

in a nerve cell, an extended fiber that conducts information from the soma to the terminal buttons; information travels along the axon in the form of an electric charge called the action potential

resting potential

the electrical charge of the action in its inactive state, when the neuron is ready to "fire"

action potential

the nerve impulse caused by a change in the electrical charge across the cell membrane of the axon; when the neuron "fires," this charge travels down the axon and causes neurotransmitters to be released by the terminal buttons

all-or-none principle

refers to the fact that all the action potential in the axon occurs either full-blown or not at all

synapse

the microscopic gap that serves as a communications link between neurons; also occur between neurons and the muscles or glands they serve

terminal buttons

tiny bulb-like structures at the end of the axon, which contain neurotransmitters that carry the neuron's message into the synapse

synaptic transmission

the relaying of information across the synapse by means of chemical neurotransmitters

dopamine

produces sensations of pleasure and reward; used by CNS neurons in voluntary movement; problems can cause schizophrenia and Parkinson's disease

serotonin

regulates sleep and dreaming, mood, pain, aggression, appetite, and sexual behavior; problems can cause depression, certain anxiety disorders, and OCD

norepinephrine

controls heart rate, sleep, sexual responsiveness, stress, vigilance and appetite; problems can cause high blood pressure and depression

acetylcholine

primary transmitter used by neurons carrying messages from CNS; involved in some kinds of learning and memory; problems can cause certain muscular disorders, and Alzheimer's disease

GABA

most prevalent inhibitory neurotransmitter in neurons of CNS; problems can cause anxiety and epilepsy

glutamate

primary excitatory neurotransmitter in CNS; involved in learning and memory; problems can cause brain damage after stroke

endorphins

control pleasurable sensations and control of pain; lowered levels resulting from opiate addiction

hindbrain

oldest part of the brain; responsible for basic life functions, including breathing, respiration, and sleeping

midbrain

second oldest brain structure; includes the reticular activating system/RAS and several neural centers that act as lower-level control centers for some limited motor, auditory, and visual functions

forebrain

newest part of brain; contains cerebral cortex, thalamus, basal ganglia, and hippothalamus

medulla

portion of brain stem associated with basic life functions, such as heartbeat and respiration

pons

portion for brain stem that is involved in coordinating muscular action and facial expression

cerebellum

portion of hindbrain that helps to control posture, balance, and muscle coordination

limbic system

group of brain structures involved with emotions, the autonomic nervous system, and olfactory processing

thalamus

portion of brain whose primary function is to relay information from sensory systems to the cerebral cortex

hippothalamus

region of hindbrain involved in regulating hunger, thirst, sex drive, body temperature, and more; secretes hormone that triggers pituitary gland

hippocampus

part of limbic system involved in long-term memory

amygdala

portion of limbic system linked to emotions and forming long-term memories

cerebral cortex

outer layer of nerve cells covering cerebrum that is responsible for most higher cognitive function

corpus callosum

bundle of nerve fibers that connects the left and right hemispheres of the brain

central fissure

long, deep groove on the lateral surface of the cerebral cortex

threshold

the level of stimulation required to trigger a neural impulse

reuptake

a neurotransmitter's reabsorption by the sending neuron

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

sympathetic nervous system

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

parasympathetic nervous system

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

reflex

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

nervous system

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

central nervous system

the brain and the spinal cord

peripheral nervous system

the sensory and motor neurons that connect the CNS to the rest of the body

lateral fissure

fissure that separates the different lobes of the cerebrum

EEG

record the brain-wave pattern of electrical activity in different parts of the brain; can detect the activity of a single neuron

CAT

a series of x-rays that, when combined, show a composite representation of horizontal slices of the brain

MRI

displays high-resolution pictures of structures and different types of soft tissues deep inside the brain

PET

provides color coded map of areas showing high activity in the brain

pituitary gland

gland located at the base of the brain producing hormones that control other glands and affect metabolism, bone growth, and sexual maturity

thyroid

an endocrine gland located in the necks of people and other vertebrates that secretes the hormones that control metabolism and growth

pancreas

a gland situated near the stomach that secretes a digestive fluid into the intestine and produces the hormone insulin

adrenal glands

small glands that produce steroid hormones, adrenaline, and noradrenaline, which help control heart rate, blood pressure, and other important bodily functions; there are two, one located on top of each kidney

epinephrine

a hormone secreted by the adrenal medulla that is stimulated by the CNS in response to stress or fear; increases heart rate, blood pressure, cardiac output, and carbohydrate metabolism

norepinephrine

hormone secreted by the adrenaline gland that increases blood pressure and rate and the depth of breathing, raises the level of blood sugar, and decreases activity in the intestines; main neurotransmitter of sympathetic nerve endings supplying the major organs and skin

thymus

an organ, located at the base of the neck, that is involved in the development of cells of the immune system, particularly T cells

gonads

sex organs in a male or female animal that make the cells needed to produce babies

ovaries

pair of organs in a female's body that produce eggs

testes

pair of male reproductive glands that produce sperm and are contained in the scrotum in most mammals

chromosomes

structures made of DNA that contain genes; located in cell nucleus; humans normally have 23 pairs, or 46 total

temperament

a person's characteristic emotional reactivity and intensity

behavior genetics

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

genome

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

heretability

the proportion of variation among individuals that we can attribute to genes; may vary on particular traits, depending on the range of populations/environments studied

interaction

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

molecular genetics

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

mutation

a random error in gene replication that leads to a change

individualism

giving priority to one's own goals and defining one's identity in terms of personal attributes rather than group identifications

collectivism

giving priority to goals of one's group (often one's extended family or work group) and defining one's identity accordingly

absolute threshold

the lowest amount of stimulation needed to detect a particular stimulus 50 percent of the time

accommodation

the process in which the lens of the eye changes shape in response to external conditions so that an object remains in focus

adaptation

the process by which the eye adjusts to varying levels of light or color

amplitude

the height of the sound waves developed by an auditory stimulus

binocular cues

a visual depth cue that requires the use of both eyes

blind spot

an area or direction in which a person's vision is obscured because no receptor cells are located there

cochlea

the snail shaped, fluid filled organ in the inner ear that contains the basilar membrane

conduction deafness

hearing loss related to problems with the ossicles, the bones of the inner ear

cones

receptors in the retina that allow us to see color, but do not function as well in low light conditions

confabulation

an imagined but plausible memory that fills in the gaps of what a person actually remembers

convergence

a binocular cue that perceives depth; the eyes converge inwards when looking at an object

cornea

the clear part of the eye that lies in front of the retina and is part of the eye's protective covering

depth perception

the ability to visually perceive the world and understand spacial relationships in order to gauge the distance between objects

eardrum

another term for the tympanic membrane

feature detection cells

cells in the cortex of the brain that respond to different characteristics of a visual stimulus

feature detection theory

an explanation for pattern recognition; the theory that we process images in terms of their constituent parts and then match the features of a pattern to those features stored in memory

figure and ground

an aspect of perception where the perceived is separated into at least two parts, with different attributes, but influencing one another

fovea

a depression near the center of the retina that is densely packed with cones; vision is most accurate here

gate control theory

theory of pain perception that there is a spinal "gate" that can be closed by the brain; closed gate would prevent brain from feeling bodily pain

frequency theory

a theory that sound is heard when pulses travel up the auditory nerve and carry the information to the brain for processing, and that the rate of this pulse exactly matches the frequency of whatever tone is heard

gustation

sense of taste

induced motion

an optical illusion in which a stationary object appears to be moving in one direction because of the movement of objects on either side in the opposite direction

iris

the colored portion of the eye that controls how much light enters through the pupil

kinesthetics

the sense of body position; also known as proprioception

law of effect

proposed by Edward Thorndike; states that a behavior is more likely to be repeated if it maximizes pleasure and/or minimizes pain

lens

the portion of the eye that changes shape to focus the visual image on the retina

light adaptation

the changes that occur in the eye to permit vision when moving from darkness to light

monocular cue

a visual depth cue that makes use of only one eye