AP Psychology Unit 1

Nature-nurture issue

The debate over the relative contributions of biology and experience to human development.

Charles Darwin

The scientist who developed the theory of natural selection, influencing evolutionary psychology.

Natural selection

The principle that inherited traits that better enable survival and reproduction are more likely to be passed on.

Evolutionary psychology

The study of how evolutionary principles help explain human behavior and mental processes.

Behavior genetics

The field that studies the relative power and limits of genetic and environmental influences on behavior.

Mutation

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

Environment

Every external influence, from prenatal nutrition to social support.

Heredity

The transmission of traits from parents to offspring through genes.

Genes

Biochemical units of heredity that make up chromosomes and influence traits.

Genome

The complete set of genetic material in an organism's chromosomes.

Identical (monozygotic) twins

Twins who develop from a single fertilized egg and are genetically identical.

Fraternal (dizygotic) twins

Twins who develop from two separate fertilized eggs and share about half their genes.

Interaction

How the effects of one factor (such as environment) depend on another (such as heredity).

Epigenetics

The study of environmental influences on gene expression that occur without changes in DNA.

Nervous system

The body's fast, electrochemical communication network consisting of all nerve cells.

Central nervous system (CNS)

Made up of the brain and spinal cord.

Peripheral nervous system (PNS)

Includes sensory and motor neurons that connect the CNS to the rest of the body.

Nerves

Bundled axons that form neural cables connecting the CNS with muscles, glands, and organs.

Sensory (afferent) neurons

Carry messages from sensory receptors toward the CNS.

Motor (efferent) neurons

Carry instructions from the CNS to the body's muscles and glands.

Interneurons

Neurons within the CNS that process information between sensory input and motor output.

Somatic nervous system

Controls the body's voluntary movements via skeletal muscles.

Autonomic nervous system (ANS)

Controls involuntary actions of internal organs and glands.

Sympathetic nervous system

Arouses the body and mobilizes energy in stressful situations.

Parasympathetic nervous system

Calms the body and conserves energy after stress passes.

Reflex

A simple, automatic response to a sensory stimulus.

Neuron

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

Cell body

The part of the neuron that contains the nucleus and keeps the cell alive.

Dendrites

Branching extensions that receive messages and conduct them toward the cell body.

Axon

The long extension of a neuron that carries messages to other neurons or muscles.

Myelin sheath

A layer of fatty tissue that insulates axons and speeds up neural impulses.

Glial cells (glia)

Support cells in the nervous system that nourish and protect neurons.

Action potential

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

Threshold

The level of stimulation required to trigger a neural impulse.

Refractory period

A brief time after a neuron fires during which it cannot fire again.

All-or-none response

The principle that a neuron either fires or does not; there's no in-between.

Synapse

The junction between the axon tip of one neuron and the dendrite of another.

Neurotransmitters

Chemical messengers that cross the synaptic gaps between neurons.

Reuptake

The process of neurotransmitters being reabsorbed by the sending neuron.

Norepinephrine

A neurotransmitter that helps control alertness and arousal.

Endorphins

Neurotransmitters that influence the perception of pain or 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 slower communication system using hormones secreted by glands.

Hormones

Chemical messengers that travel through the bloodstream and affect other tissues.

Psychoactive drug

A chemical substance that alters perceptions and moods.

Substance use disorder

A disorder characterized by continued substance craving and use despite significant life disruption.

Depressants

Drugs that reduce neural activity and slow body functions.

Tolerance

The diminishing effect of a drug after repeated use, requiring larger doses to achieve the same effect.

Addiction

Compulsive drug craving and use despite harmful consequences.

Withdrawal

The discomfort and distress that follow discontinuing an addictive drug or behavior.

Barbiturates

Depressant drugs that reduce anxiety but impair memory and judgment.

Opioids

Drugs that depress neural activity, temporarily lessening pain and anxiety.

Stimulants

Drugs that excite neural activity and speed up body functions.

Hallucinogens

Drugs that distort perceptions and evoke sensory images without input.

Near-death experience

An altered state of consciousness reported after a close brush with death.

Biological psychology

The scientific study of the links between biological and psychological processes.

Biopsychosocial approach

An integrated viewpoint that incorporates biological, psychological, and social-cultural factors.

Levels of analysis

The differing complementary views for analyzing any given phenomenon.

Neuroplasticity

The brain's ability to change and adapt, especially during childhood or after damage.

Lesion

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

EEG (electroencephalogram)

A recording of electrical activity in the brain using electrodes.

MEG (magnetoencephalography)

Measures magnetic fields from the brain's natural electrical activity.

CT (computed tomography) scan

A series of X-ray images taken from different angles and combined.

PET (positron emission tomography) scan

Shows brain activity by detecting where radioactive glucose goes.

MRI (magnetic resonance imaging)

Uses magnetic fields and radio waves to produce images of soft tissue.

fMRI (functional MRI)

Reveals blood flow and brain activity by comparing MRI scans.

Hindbrain

Controls basic biological functions like breathing and heart rate.

Midbrain

Integrates sensory information and relays it upward.

Forebrain

Includes complex thinking, emotions, and personality.

Brainstem

The oldest part of the brain responsible for automatic survival functions.

Medulla

Controls heartbeat and breathing.

Thalamus

is the brain's sensory control center.

Reticular formation

is a nerve network in the brainstem that plays a role in arousal.

Cerebellum

helps coordinate voluntary movement and balance.

Limbic system

is a group of brain structures involved in emotions and memory.

Amygdala

is involved in emotion, especially fear and aggression.

Hypothalamus

regulates hunger, thirst, body temperature, and sexual behavior.

Hippocampus

is involved in memory formation and spatial navigation.

Cerebral cortex

is the brain's outer layer of neural tissue, involved in higher functions.

Frontal lobes

are involved in speaking, planning, and judgment.

Parietal lobes

process sensory input for touch and body position.

Occipital lobes

include areas that receive visual information.

Temporal lobes

include areas responsible for hearing and language.

Motor cortex

controls voluntary movements.

Somatosensory cortex

registers and processes body touch and movement sensations.

Association areas

are parts of the cerebral cortex involved in higher mental functions.

Neurogenesis

is the formation of new neurons.

Corpus callosum

is the large band of neural fibers connecting the two brain hemispheres.

Roger Sperry

was a researcher known for work with split-brain patients.

Michael Gazzaniga

also studied split-brain patients to understand hemispheric specialization.

Split brain

is a condition in which the two hemispheres of the brain are isolated.

Consciousness

is our awareness of ourselves and our environment.

Cognitive neuroscience

is the study of the brain activity linked with cognition.

Dual processing

is the idea that information is often processed on separate conscious and unconscious tracks.

Blindsight

is a condition where a person can respond to visual stimuli without consciously experiencing it.

Parallel processing

is processing many aspects of a problem simultaneously.

Sequential processing

is processing one aspect of a problem at a time.

Sleep

is a periodic, natural loss of consciousness.

Circadian rhythm

is the biological clock that regulates bodily rhythms.