Unit 1 Key Terms (Myers' Psychology for the AP Course)

Vocabulary-style flashcards covering key terms from Myers' AP Psychology Unit 1 notes.

nature–nurture issue

The longstanding debate over the relative contributions of genes and experience to psychological traits and behaviors; today they are viewed as interacting.

natural selection

Inherited traits that improve an organism’s survival and reproduction in a given environment are more likely to be passed on.

evolutionary psychology

The study of how evolution has shaped behavior and mind using natural selection principles.

behavior genetics

The study of how genetic and environmental influences interact to influence behavior.

mutation

A random error in gene replication that leads to a change.

environment

All non-genetic influences, from prenatal nutrition to experiences with people and things.

heredity

The genetic transfer of characteristics from parents to offspring.

genes

Biochemical units of heredity.

genome

The complete set of instructions for making an organism.

identical (monozygotic) twins

Twins who develop from a single fertilized egg that splits; genetically identical.

fraternal (dizygotic) twins

Twins who develop from separate fertilized eggs; not more genetically similar than ordinary siblings.

interaction

The interplay that occurs when the effect of one factor depends on another factor.

epigenetics

The study of how environments can influence gene expression without changing the DNA sequence.

nervous system

The body’s fast, electrochemical communication network of all nerve cells in the CNS and PNS.

central nervous system (CNS)

The brain and spinal cord.

peripheral nervous system (PNS)

Nerves that connect the CNS to the rest of the body.

nerves

Bundled axons forming neural cables that connect the CNS with muscles, glands, and sensory organs.

sensory (afferent) neurons

Neurons that carry incoming information from the body’s tissues and receptors to the brain and spinal cord.

motor (efferent) neurons

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

interneurons

Neurons within the brain and spinal cord that process information between sensory inputs and motor outputs.

somatic nervous system

Division of the PNS that controls the body's skeletal muscles.

autonomic nervous system (ANS)

Part of the PNS that controls glands and internal organs; sympathetic arouses, parasympathetic calms.

sympathetic nervous system

Division of the ANS that arouses the body and mobilizes energy.

parasympathetic nervous system

Division of the ANS that calms the body and conserves energy.

reflex

A simple, automatic response to a sensory stimulus.

neuron

A nerve cell; the basic building block of the nervous system.

cell body

Part of a neuron containing the nucleus; the cell’s life-support center.

dendrites

Branching extensions that receive and integrate messages toward the cell body.

axon

The neuron extension that passes messages to other neurons, muscles, or glands.

myelin sheath

Fatty tissue wrapping some axons that speeds transmission of neural impulses.

glial cells (glia)

Cells that support, nourish, and protect neurons.

action potential

A neural impulse; a brief electrical charge traveling down an axon.

threshold

The level of stimulation required to trigger a neural impulse.

refractory period

A resting pause after firing; neurons cannot fire again until resting state is restored.

all-or-none response

A neuron fires at full strength or not at all.

synapse

The junction between the sending and receiving neurons; gap is the synaptic cleft.

neurotransmitters

Chemical messengers that cross the synapse and influence neural impulses.

reuptake

Reabsorption of a neurotransmitter by the sending neuron.

endorphins

Natural opioid-like neurotransmitters linked to pain control and pleasure.

agonist

A molecule that increases a neurotransmitter’s action.

antagonist

A molecule that inhibits or blocks a neurotransmitter’s action.

endocrine system

The body’s slow chemical communication system; glands secrete hormones into the bloodstream.

hormones

Chemical messengers produced by endocrine glands; travel through the bloodstream.

psychoactive drug

A chemical substance that alters brain function, affecting perception and mood.

substance use disorder

Disorder characterized by continued substance use despite life disruption.

depressants

Drugs that reduce neural activity and slow body functions.

tolerance

Diminishing effect with regular use of the same dose, leading to larger doses.

addiction

Compulsive substance use (or behavior) despite harmful consequences.

withdrawal

Discomfort and distress following discontinuation of an addictive drug or behavior.

barbiturates

Drugs that depress CNS activity, reducing anxiety but impairing memory.

opioids

Opium and derivatives; depress neural activity and relieve pain.

stimulants

Drugs that excite neural activity and speed up body functions.

hallucinogens

Psychedelic drugs that distort perceptions and evoke sensory images.

near-death experience

Altered state of consciousness after a close brush with death, often drug-like in experience.

biological psychology

Scientific study of links between biological processes and psychological states.

biopsychosocial approach

Integrated approach considering biological, psychological, and social-cultural factors.

levels of analysis

Different complementary viewpoints (biological to social-cultural) for analyzing phenomena.

neuroplasticity

Brain’s ability to change by reorganizing or building new pathways based on experience.

lesion

Tissue destruction in the brain (natural, surgical, or experimental).

EEG (electroencephalogram)

An amplified recording of brain electrical activity via scalp electrodes.

MEG (magnetoencephalography)

A brain-imaging technique measuring magnetic fields from brain activity.

CT (computed tomography) scan

X-ray images compiled into a 3D representation of brain structure.

PET (positron emission tomography)

Technique detecting brain activity by tracing radioactive glucose in use.

MRI (magnetic resonance imaging)

Imaging technique using magnetic fields to produce detailed brain anatomy.

fMRI (functional MRI)

MRI that shows brain activity by measuring blood flow; reveals function and structure.

hindbrain

Includes medulla, pons, and cerebellum; governs basic life functions and coordination.

midbrain

Above hindbrain; connects to forebrain and transmits auditory/visual information.

forebrain

Contains cerebral cortex, thalamus, and hypothalamus; handles complex cognition and sensation.

brainstem

Central core of the brain, automatic survival functions; includes medulla and pons.

medulla

Hindbrain region controlling heartbeat and breathing.

thalamus

Forebrain’s sensory relay center; routes messages to cortex and back.

reticular formation

Nerve network through brainstem to thalamus; regulates arousal.

cerebellum

“Little brain” responsible for processing input, coordinating movement, balance, and memory.

limbic system

Emotion and drive-centered system including amygdala, hypothalamus, hippocampus, thalamus, and pituitary.

amygdala

Two almond-shaped clusters linked to emotion.

hypothalamus

Limbic structure below the thalamus; maintains homeostasis and links to endocrine system.

hippocampus

Limbic center that processes explicit memories for storage.

cerebral cortex

Thin, outer covering of the brain; higher-order processing and control.

frontal lobes

Behind the forehead; involved in language, movement, planning, and executive functions.

parietal lobes

Top-rear region; registers touch and body position.

occipital lobes

Back of the head; receive visual information.

temporal lobes

Above the ears; contain auditory areas and support language processing.

motor cortex

Rear of the frontal lobes; controls voluntary movements.

somatosensory cortex

Front of the parietal lobes; processes touch and movement sensations.

association areas

Regions not primarily motor or sensory; involved in higher mental functions.

neurogenesis

Formation of new neurons.

corpus callosum

Large band of fibers connecting the two hemispheres and carrying messages.

split brain

Condition from surgery that separates hemispheres by cutting corpus callosum.

consciousness

Our subjective awareness of ourselves and the surrounding world.

cognitive neuroscience

Interdisciplinary study of brain activity linked with cognition.

dual processing

Information is processed on separate conscious and unconscious tracks.

blindsight

Ability to respond to visual stimuli without conscious awareness.

parallel processing

Processing multiple aspects of a problem simultaneously.

sequential processing

Processing one aspect at a time, often used for difficult tasks.

sleep

Periodic, natural loss of consciousness distinct from coma or anesthesia.

circadian rhythm

Biological 24-hour cycle regulating temperature, wakefulness, and more.

REM sleep

Rapid eye movement sleep; vivid dreams; muscles are relaxed but body systems are active.

alpha waves

Slow brain waves typical of a relaxed, awake state.

NREM sleep

Non-REM sleep; all stages of sleep excluding REM.

hallucinations

False sensory experiences, such as seeing something absent.