AP PSYCH- chapter 3 vocab

Biological psych

scientific study of the links between biological (genetic, neural, hormonal) and psychological processes

neuron

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

application: reflex action

dendrites

a neuron’s bushy,

branching extensions that receive

messages and conduct impulses

toward the cell body

application: like a tree → the dendrites are the branches of the neuron

axon

passes messages through its

branches to other neurons or to

muscles or glands

application: axon away → carries signals away

myelin shealth

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

Action potential

a neural impulse; a brief electrical charge that travels down the axonRe

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 neurons 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 the cell body of the receiving neuron. The tiny gap at this junction is called a synaptic gap or synaptic cleft

application: gaps in ladder

neurtransmitters

chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, neurotransmitters travel across the

synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse.

Reuptake

a neurotransmitters reabsorption by sending neurons

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, inhabits or block a response

application: someone cutting you in line

Nervous system

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

Central nervous system (CNS)

brain and spinal cord

peripheral nervous system (PNS)

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

nerves

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

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

somatic nervous system

the division of the peripheral nervous system that controls the body’s

skeletal muscles. Also called the skeletal nervous system.

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.

reflex

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

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, the pituitary regulates growth and controls other endocrine glands.

Lesion

tissue destruction. a brain lesion is a naturally or experimentally caused destruction of brain tissue

EEG

an amplified recording of the waves of electrical activity sweeping across the brain’s surface. These waves are measured by electrodes placed on the scalp.

CT

a series of X-ray photographs taken from different angles and combined by computer into a composite representation of a slice of the brain’s structure.

PET

a visual

display of brain activity that detects

where a radioactive form of glucose

goes while the brain performs a

given task.

MRI

a technique that uses

magnetic fields and radio waves

to produce computer-generated

images of soft tissue. MRI scans

show brain anatomy.

fMRI

a

technique for revealing bloodflow

and, therefore, brain activity by

comparing successive MRI scans.

fMRI scans show brain function as

well as its structure.

brainstem

the oldest part and

central core of the brain, beginning

where the spinal cord swells as it

enters the skull; the brainstem is

responsible for automatic survival

functions.

medulla

he base

of the brainstem; controls heartbeat

and breathing.

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.

reticular formation

a nerve

network that travels through the

brainstem and thalamus and plays

an important role in controlling

arousal.

cerebellum

the “little brain” at the

rear of the brainstem; functions

include processing sensory input,

coordinating movement output and

balance, and enabling nonverbal

learning and memory.

limbic system

neural system

(including the hippocampus,

amygdala, and hypothalamus)

located below the cerebral

hemispheres; associated with

emotions and drives.

amygdala

two

lima-bean-sized neural clusters in

the limbic system; linked to emotion.

hypothalamus

a neural structure lying below

(hypo) the thalamus; it directs several

maintenance activities (eating,

drinking, body temperature), helps

govern the endocrine system via

the pituitary gland, and is linked to

emotion and reward.

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; they

may also play a role in learning and

thinking.

frontal lobes

portion of the

cerebral cortex lying just behind the

forehead; involved in speaking and

muscle movements and in making

plans and judgments.

application: frontal →future

paretial lobes

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 lobes

portion of the cerebral cortex lying

at the back of the head; includes

areas that receive information from

the visual fields.

temporal lobes

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 area

area at

the front of the parietal lobes that

registers and processes body touch

and movement sensations.

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.

cognitive neuroscience

the

interdisciplinary study of the brain

activity linked with cognition

(including perception, thinking,

memory, and language).

dual processing

the principle

that information 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.

enviroment

every external

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.

identical twins (monozygotic twins)

wins who develop from

a single fertilized egg that splits

in two, creating two genetically

identical organisms.

fraternal twins (dizygotic twins)

twins who develop from separate

fertilized eggs. They are genetically

no closer than brothers and sisters,

but they share a fetal environment.

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. The heritability

of a trait 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.

evolutionary psychology

the

study of the evolution of behavior

and the mind, using principles of

natural selection.

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