AP Psych Unit 2

heredity

the passing of traits from parent to offspring

nature vs. nuture

the longstanding controversy over the relative contributions that genes and experience make to the development of psychological traits and behaviors

dizygotic twins (fraternal)

twins who develop from separate fertilized eggs. They are genetically no closer than brothers and sisters, but they share a fetal environment

monozygotic twins (identical)

twins who develop from a single fertilized egg that spilts into two creating two genetically identical organisms

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.

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

epigenetics

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

behavioral genetics

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

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

reuptake

a neurotransmitter's reabsorption by the sending neuron

resting potential

the polarization of cellular fluid within a neuron that provides the potential to produce an action

acetylcholine

a neurotransmitter that enables learning, memory, and sleep. As well as, voluntary movement and muscle contraction

dopamine

a neurotransmitter that influences movement, learning, attention, and rewards (related to addictions)

serotonin

a neurotransmitter that affects hunger, sleep, appetite, and mood regulation

epinephrine/norepinephrine

a neurotransmitter involved in arousal and alertness. "Fight or Flight" response (norepinephrine slows down appetite and digestions during it)

GABA

a major inhibitory neurotransmitter, inhibits excitation and anxiety (calming)

glutamate

a major excitatory neurotransmitter; involved in memory and learning

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

receptor sites

holes in the surface of the dendrites or certain cells of the muscles and glands, which are shaped to fit only certain neurotransmitters

soma

cell body of a neuron

glial cells

cells in the nervous system that support, nourish, and protect neurons; also may play a role in learning and thinking

terminal buttons

small knobs at the end of axons that secrete chemicals called neurotransmitters

nodes of ranvier

gaps in the myelin sheath

vesicles

small membrane sacs that specialize in moving products into, out of, and within a cell

spinal reflexes

simple pathways in the nervous system that rapidly generate muscle contractions (single sensory neuron + single motor neuron)

glands

groups of cells that release hormones

pituitary gland

gland that controls other glands (aka master gland)

adrenal glands

glands that secrete epinephrine/norepinephrine for fight-or-flight

cortisol

stress hormone

thyroid gland

gland that regulates cellular metabolism

pineal gland

gland that produces melatonin to help regulate circadian rhythms

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

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

motor neurons (efferent)

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

sensory neurons (afferent)

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

endocrine system

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

hormones

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues

adrenaline

a hormone released into the bloodstream in response to physical or mental stress

depressants

drugs (such as alcohol, barbiturates, and opiates) that reduce neural activity and slow body functions

stimulants

drugs (such as caffeine, nicotine, cocaine, and Ecstasy) that excite neural activity and speed up body functions

opiates

opium and its derivatives, such as morphine and heroin; they depress neural activity, temporarily lessening pain and anxiety

barbiturates

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

addiction

compulsive drug craving and use, despite adverse consequences

tolerance

the diminishing effect with regular use of the same dose of a drug, requiring the user to take larger and larger doses before experiencing the drug's effect

psychoactive drugs

a chemical substance that alters perceptions and moods

withdrawal

the discomfort and distress that follow discontinuing the use of an addictive drug

physical dependence

a physiological need for a drug, marked by unpleasant withdrawal symptoms when the drug is discontinued

psychological dependence

a psychological need to use a drug, such as to relieve negative emotions

medulla

the base of the brainstem; controls heartbeat, breathing, and blood pressure

pons

the part of the brainstem that helps coordinate movement, regulate sleep cycle, and facial expressions

reticular formation

a nerve network that regulates arousal and filters incoming stimuli for importance

thalamus

the brain's sensory control center; it routes incoming messages from all senses (except smell)

cerebellum

the "little brain" at the rear of the brainstem; maintains balance and coordinating movement, also nonverbal learning and memory

amydgala

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

hypothalamus

a neural structure lying below the thalamus; it directs several maintenance activities (eating, drinking, body temperature), monitor and regulate your "drives", and helps communicate with the endocrine system

hippocampus

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

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

limbic system

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

endorphins

natural, opiate-like neurotransmitters linked to pain relief, stress reduction, and feelings of pleasure

frontal lobe

the portion of the cerebral cortex lying just behind the forehead; involved in speaking, muscle movements, impulse control, in making plans and judgment/logic (broca's area)

pariental 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, also linked to mathematics and spatial awareness

occipital lobe

portion of the cerebral cortex lying at the back of the head; includes areas that receives and processes sensory information related to vision

temporal lobe

portion of the cerebral cortex lying roughly above the ears; includes areas that receive and process sensory information related to hearing (wernicke's area)

motor cortex

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

somatosensory cortex

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

assosciation 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

corpus callosum

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

contralaterality

control of one side of your body by the other side of your brain

polarization

establishes distinct molecular structures to generate a single axon and multiple dendrites

depolarization

the process during the action potential when sodium is rushing into the cell causing the interior to become more positive

excitatory

chemical secreted at terminal button that causes the neuron on the other side of the synapse to generate action potential (to fire)

inhibitory

chemical secreted at terminal button that reduces or prevents neural impulses in the postsynaptic neuron

cerebral cortex

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

oxytocin

a hormone that functions as a neurotransmitter in the brain. Triggered by almost any form of social bonding or positive physical contact

Broca's area

controls the production of speech (part of frontal lobe)

Wernicke's area

responsible for the understanding of language, both written and spoken (part of the temporal lobe)

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

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.

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

CAT/CT (computerized axial tomography)

creates a computerized image using x-rays passed through the brain to show structure and/or the extent of a lesion

MRI (magnetic resonance imaging)

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

fMRI (functional magnetic resonance imaging)

a technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans. Shows brain function.

lesion

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

aphasia

impairment of language, usually caused by left hemisphere damage either to Broca's area (impairing speaking) or to Wernicke's area (impairing understanding)

apraxia

inability to perform particular purposive actions, as a result of brain damage

agonosia

difficulty with processing of sensory input