AP Psych Unit 1: Biological Bases of Behavior

nature vs nurture

name for a controversy in which it is debated whether genetics or environment is responsible for driving behavior

Charles Darwin

English natural scientist who formulated a theory of evolution by natural selection (1809-1882)

Natural Selection

A process resulting in the evolution of organisms best adapted to the environment.

Evolutionary Psychology

the study of the roots of behavior and mental processes using the principles of natural selection

behavior genetics

the field that seeks to discover the influence of heredity and environment on individual differences in human traits and development

mutation

change in a DNA sequence that affects genetic information

heredity

the transmission of traits from one generation to the next

genes

the biochemical units of heredity that make up the chromosomes; a segment of DNA capable of synthesizing a protein

genome

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

identical (monozygotic) twins

develop from a single fertilized egg that splits in two, creating two genetically identical organisms

fraternal (dizygotic) twins

Develop from separate fertilized eggs. They are genetically no closer than ordinary brothers and sisters, but they share a prenatal environment

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

central nervous system

consists of the brain and spinal cord

peripheral nervous system

A division consisting of all nerves that are not part of the brain or spinal cord.

sympathetic nervous system

prepares the body for action in challenging or threatening situations

parasympathetic nervous system

helps the body return to a normal resting state

sensory neurons

carry impulses from the sense organs to the spinal cord and brain

motor neurons

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

interneurons/relay neurons

communicate within the brain and spinal cord and between sensory and motor neurons

autonomic nervous system

The part of the PNS that controls the glands and the muscles of the internal organs (involuntary movements).

somatic nervous system

Division of the PNS that controls the body's skeletal muscles (voluntary movements).

neuron

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

neurotransmitter

chemical messengers that cross the synaptic gaps between neurons

synaptic gap

space between the axon terminal of one neuron and the receptors of the next neuron

excitatory

accelerates neuron's firing speed

inhibitory

slows neuron's firing speed

agonist

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

antagonist

a molecule that inhibits or blocks a neurotransmitter's action

exogenous

produced from without; due to external causes

endogenous

produced within the body

dopamine

A neurotransmitter associated with movement, attention and learning and the brain's pleasure and reward system.

serotonin

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

acetylcholine

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

endorphins

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

glutamate

The most common neurotransmitter in the brain, involved in memory. Excitatory.

GABA

An inhibitory neurotransmitter in the brain that promotes relaxation and sleep and blocks intrusive thoughts.

norepinephrine (noradrenaline)

A neurotransmitter and hormone involved in arousal, as well as in learning and mood regulation

substance p

A neurotransmitter that is involved in the transmission of pain messages to the brain.

epinephrine (adrenaline)

A neurotransmitter and hormone produced by adrenal medulla; increases heart rate. It is part of the body's "fight or flight" reaction.

pituitary gland

endocrine "master" gland at the base of the brain; regulates stress, growth, and reproduction

testosterone

Male sex hormone (females have much smaller amounts of it) secreted by the testes and ovaries.

estrogen

Female sex hormone that signals certain physical changes at puberty and controls the maturation of eggs (men have much smaller amounts of it)

oxytocin

A hormone and neurotransmitter produced in the hypothalamus and released by the posterior pituitary that stimulates uterine contractions during childbirth and milk ejection during breastfeeding. The "love, bonding, and trust" hormone.

melatonin

A hormone manufactured by the pineal gland that produces sleepiness.

Substance Use

taking moderate amounts of a substance in a way that doesn't interfere with functioning

Substance Abuse

overindulgence in or dependence on an addictive substance, especially alcohol or drugs.

Substance Tolerance

desired effect requires larger substance amounts

Substance Withdrawal

specific syndrome caused by the cessation of or reduction in heavy prolonged substance use

depressants

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

stimulants

drugs (such as caffeine, nicotine, and the more powerful amphetamines, cocaine, and Ecstasy) that excite neural activity and speed up body functions.

hallucinogens

psychedelic ("mind-manifesting") drugs, such as LSD and psilocybin, that distort perceptions and evoke sensory images in the absence of sensory input

opioids

any drug or agent with actions similar to morphine (mimicking the neurotransmitter endorphins).

neuroplasticity

the ability within the brain to constantly change both the structure and function of many cells in response to experience or learning.

phrenology

The study of the conformation of the skull based on the belief that it is indicative of mental faculties and character.

brain stem

Connection to spinal cord. Filters information flow between peripheral nervous system and the rest of the brain.

cerebellum

the "little brain" at the rear of the brainstem; functions include processing sensory input and coordinating movement output and balance

midbrain

Region between the hindbrain and the forebrain; it is important for hearing and sight.

pons

A brain structure that relays information from the cerebellum to the rest of the brain

medulla oblongata

the continuation of the spinal cord within the skull, forming the lowest part of the brainstem and containing control centers for the heart and lungs.

reticular formation

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

the limbic system

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

hippocampus

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

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

frontal lobe

A region of the cerebral cortex that has specialized areas for movement, abstract thinking, planning, memory, and judgement

parietal lobe

A region of the cerebral cortex whose functions include processing sensory stimuli.

temporal lobe

A region of the cerebral cortex responsible for hearing and language.

occipital lobe

A region of the cerebral cortex that processes visual information

prefrontal cortex

the frontmost portion of the frontal lobes, especially prominent in humans; important for attention, working memory, decision making, appropriate social behavior, and personality

motor area

A region of the frontal lobe involved in regulating movement

somatosensory area

An area of the parietal lobe that processes sensory information such as touch

Wernicke's Area

controls language reception - a brain area involved in language comprehension and expression; usually in the left temporal lobe

Broca's Area

controls language expression - an area, usually in the left frontal lobe, that directs the muscle movements involved in speech.

fMRI (functional MRI)

A technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans. fMRI scans show brain function.

PET (positron emission tomography)

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

CT scan (computed tomography)

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

MRI (magnetic resonance imaging)

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

EEG (electroencephalography)

the recording of brain activity as waves, which are identified on the basis of the speed of the rhythmic activity.

MEG (magnetoencephalography)

technique that measures brain activity by detecting tiny magnetic fields generated by the brain

neurogenesis

creation of new neurons in the adult brain

corpus callosum

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

association areas

areas of the cerebral cortex that are composed of neurons that help provide sense and meaning to information registered in the cortex

Michael Gazziniga / Roger Sperry Contributions

Divided the brains of cats, dogs, and monkeys into two parts with no serious ill effects. Repeated these surgeries on humans to treat epileptic seizures. Found the left hemisphere is dominant in terms of speech and language, while the right hemisphere is dominant in terms of visual-motor tasks.

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

Awareness of ourselves and our environment

cognitive neuroscience

A field that attempts to understand the links between cognitive processes and brain activity.

dual processing

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

parallel processing

the processing of many aspects of a problem simultaneously

sequential processing

processing one aspect of a problem at a time; generally used to process new information or to solve difficult problems

sleep

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

circadian rhythm

A physiological cycle of about 24 hours that is present in all eukaryotic organisms and that persists even in the absence of external cues.

REM sleep

the stage of sleep marked by rapid eye movements, dreaming, and paralysis of motor systems

alpha waves

brain waves that indicate a state of relaxation or light sleep

NREM sleep

Quiet, typically dreamless sleep in which rapid eye movements are absent; divided into four stages; also called quiet sleep.

hallucinations

perceptions that have no direct external cause

hypnagogic sensations

bizarre experiences, such as jerking or a feeling of falling or floating weightlessly, while transitioning to sleep

delta waves

long, slow waves that indicate the deepest stage of sleep

suprachiasmatic nucleus (SCN)

a pair of cell clusters in the hypothalamus that controls circadian rhythm and causes the pineal gland to adjust melatonin production, thus modifying our feelings of sleepiness

insomnia

recurring problems in falling or staying asleep