AP Psych U2 - Biological Factors

nervous system, endocrine system, parts of the brain, sleep

phrenology

the outdated study of bumps on the skull to reveal traits; popularized by Franz Gull

localization of function

the idea that various brain regions have particular functions

biosychosocial

biological, social, and psychological systems working together

neuron

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

cell body

contains the nucleus of a neuron; life-support center of the neuron

dendrite fibers

short fibers of a neuron that surround the cell body and receive and integrate messages from other neurons

axon fibers

long fiber extending out of a neuron that passes messages to other cells in the body

myelin sheath

a fatty tissue layer that insulates axon fibers and can increase transmission speed

glial cells

support, nourish, and protect neurons; also play a role in learning, thinking, and memory

action potential

a neural impulse; a breif electrical charge that travels down an atom

resting potential

when the negatively charged interior and positively charged exterior of a neuron is separated

depolarization

the loss of inside/outside charge difference that happens during a neuron’s action potential

excitatory and inhibitory signals

“gas pedal” and “brake” in a neuron, decides when an action potential happens by if a threshold is crossed

refractory period

a short resting pause between action potentials that allows the axon to return to its resting state

all-or-none response

a reaction in a neuron either firing with full-strength or not firing at all

synapse

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

reputake

the process in which the sending neuron absorbs excess neurotransmitters after they send an impulse

neurotransmitters

chemical messengers that cross the synaptic gaps between neurons, influencing whether that neuron will generate a neural impulse

acetylcholine (ACh)

enables muscle action, learning, and memory

dopamine

influences movement, learning, attention, and emotion

serotonin

affects mood, hunger, sleep, and arousal

norepinephrine

helps control alertness and arousal

GABA (gamma-aminobutyric acid)

a major inhibitory neurotransmitter

glutamate

A major excitatory neurotransmitter; involved in memory

endorphines

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

agonist vs antagonist molecules

1) increases a neurotransmitter’s actions

2) decreases a neurotransmitter’s actions

lesion

deliberate destruction of normal or defective brain tissue, leaving the surrounding tissue unharmed

EEG

records waves of electrical activity that sweep across the brain’s surface; electrodes placed on the scalp

activity of the brain

MEG

measures magnetic fields from brain’s natural electrical activity

activity of the brain

CT scan

a series of x-ray scans are taken from multiple views (especially cross sections)

anatomy of the brain

PET scan

detects where a radioactive form of glucose when the brain is told to perform a task

activity of the brain

MRI scan

uses magnetic fields and radio waves to produce detailed images of soft tissue, show different structures, and can reveal fluid in the brain

anatomy of the brain

fMRI scan

shows blood flow, oxygen structures, and function by comparing successive MRI scans

anatomy of the brain

plasticity and neurogenesis

two ways that the brain “self-repairs”

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

formed by either underdeveloped neurons or by stem cells that can become neurons

nervous system

the body’s electrochemical communication network, consisting of all the nerve cells of the peripheral and central branches

central nervous system

consists of the neurons in the brain and spinal cord

somatic nervous system

enables voluntary control of the body’s skeletal nervous system

also called skeletal nervous system

automatic nervous system (ANS)

controls the glands and muscles of the internal organs

operates on its own but can be purposefully overridden

sympathetic nervous system

arouses and mobilizes energy

alerts body by raising heartbeat and blood pressure, slow digestion, etc (“fight or flight” response)

parasympathetic nervous system

calms the body from the sympathetic nervous system, conserving its energy

reflexes

a simple and automatic response to a sensory stimulus (such as a knee-jerk response)

peripheral nervous system

consists of sensory and motor neurons that branch out throughout the body and connect back to brain and spinal cord

afferent neurons (sensory)

carry incoming information from the body tissues and sensory receptors to the CNS

efferent neurons (motor)

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 process information between the sensory inputs and outputs

any neuron that does not have sensory or motor functions

the endocrine system

the body’s slow chemical communication system

a set of glands that secrete hormones into the blood stream

adrenal glands

pair of glands that are just above the kidneys

secrete hormones that arouse the body in times of stress (epinephrine and norepinephrine)

thyroid glands

pair found at the front of the neck under the voice box

affects metabolism

parathyroids

two pairs found next to the two thyroid glands in the neck

regulates calcium in blood

pancreas

found just behind the stomach and under the ribs

regulates sugar in blood

testes/ovaries

found in the pelvis

secretes sex hormones (testosterone and estrogen)

pituitary gland

found in the base of the brain (near the hypothalamus)

most influential gland: regulates growth and controls other endocrine glands

pineal gland

in the mid-line of the brain

secretes melatonin

hormones

chemical messengers that are manufactured by the endocrine glands, travel in the blood stream, and affect other tissues

adrenaline

fight or flight, beneficial in short bursts

produced by the adrenal glands

oxytocin

reproduction, social bonding, chlidbirth process

produced by pituitary gland

cortisol

stress hormone, helps body with threats

produced by adrenal glands

testosterone

sexual arousal and competition

produced by testes

estrogen

reproduction and sexual desire

produced by ovaries

leptin

responsible for turning off hunger

produced by tissue

ghrelin

responsible for turning on hunger

produced by pituitary gland

melatonin

helps turn on sleep process

produced by pineal gland

the brainstem

oldest part and central core of the brain

automatic survival functions

medulla

base of the brainstem; controls heartbeat and breathing

damage → no life

pons

above medulla in brainstem; coordinates movements and controls sleep

damage → braindead

thalamus

sensory control center (except for smell); crossroads of nervous system, routes information to higher brain function

damage → unconsciousness or coma

reticular formation (or reticular activating system)

runs through the brainstem into the thalamus; controls waking and alertness

damage → coma, inability to wake up

cerebellum

“little brain” at rear of the brainstem; nonverbal learning, skill memory, gross motor skills

damage → inhibit basic movement and balance, affected when drunk

the limbic system

neural system located below central hemispheres

associated with emotions and drives (regulatory)

amygdala

two clusters located in front middle of the brain; associated with emotion (primarily aggression and fear)

damage → heightened aggression or fear when stimulated, overly mellow and unbothered when removed

hypothalamus

below thalamus; directs several maintenance activities, helps govern endocrine system via pituitary gland, maintain homeostasis

damage → homeostasis is lost and imbalance in weight, emotions, sleep cycle, etc.

hippocampus

memory of facts and events

damage → short and long term memory loss, becomes less effective as we age

cerebral cortex

the interconnected neural cells covering the outer hemispheres; body’s ultimate control and information processing

the larger [_] gets, the more adaptable the organism becomes

frontal lobes

lies behind the forehead; motor (voluntary) movement and personality

damage → personality and mood changes, poor attention, movement difficulties

motor cortex

strip at the rear of the frontal lobes; controls voluntary movements

damage → impaired movement

Broca’s Area

in frontal lobes; responsible for muscles that produce speech

damage →

parietal lobes

top of the head and toward the back; sensory (touch) info, body position, spatial awareness

damage → spatial disorientation an navigation issues, difficulty in drawing, trouble telling left from right

somatosensory cortex

strip at the front of the parietal lobes; registers and processes body touch and movement sensations

damage → numbness or tickling sensations

temporal lobe

roughly between and above the ears; processes auditory info

damage → loss of hearing and difficulty understanding spoken word

Wernicke’s Area

in the temporal lobe; interprets spoken language

damage → impacts ability to understand language

prefrontal cortex

found in front parts of the frontal lobe; enables judgment, planning, and processing of new memories

damage → prohibit someone from planning ahead or remembering something, may also lead to personality change

corpus callosum

large band of neural fibers connecting the left and right brain hemispheres, carrying messages between them

split brain

condition resulting from surgery that isolates the brain’s two hemispheres

consciousness

subjective awareness of ourselves and our environment

blindsight

condition in which a person can respond do a visual stimulus without consciously experiencing it

ex. pupils register a flash unconsciously

parallel processing

processing many aspects of a problem simultaneously; used to process well-learned info

sequential processing

processing one aspect of a problem at a time; used to process new info

contralateral control

right side of the brain receives sensory info and controls the motor function of the left slide of the body and vise-versa

brain lateralization

tasks specialized to each hemisphere

right → inferences, spatial and creative tasks, facial recognition

left → spoken language, sequence, logic, mathematics, analysis

heredity

genetic transfer of characteristics from parents to offspring

environments

every non-genetic influence

chromosomes

threadlike structures made of DNA molecules that contain the genes

genes

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 the genetic material in that organism’s chromosomes

identical twins (monozygotic)

develop from a single fertilized egg that splits in two

share 100% of their genetic material

fraternal twins (dizygotic)

develop from separate fertilized eggs

shares 50% of their genetic material

heritability

statistical concept that describes how much variation between traits can be attributed to genetics

as environments become more similar, genetics can be attributed more to a given trait

gene-enviroment interaction

the interplay that occurs when the effect of one factor (ie. environment) depends on another factor (ie. genes)