UNIT 1 AP PSYCH

Heredity

Definition: Passing traits from parents to kids through genes.

Example: Eye color or risk of depression.

Nature

Definition: What you’re born with — your genes.

Example: Natural talent or temperament.

Nurture

Definition: What the environment teaches you.

Example: Growing up around music → love instruments.

Environmental Factors

Definition: Surroundings that affect you (family, culture, experiences).

Example: Moving to a new country changes your behavior.

Evolutionary Perspective

Definition: Behavior explained by survival and reproduction advantages.

Example: Fear of snakes helped ancestors stay alive.

Twin Studies

Definition: Compare identical and fraternal twins to see genetic influence.

Example: Identical twins more alike
→ genes matter.

Adoption Studies

Definition: Compare adopted kids to birth vs adoptive parents.

Example: Similar to birth parents
→ genetics, not environment.

Family Studies

Definition: See how traits run in families.

Example: If anxiety runs in close relatives, genetics may play a role.

Eugenics

Definition: A discredited idea of “improving” humans by selective breeding.

Example: Historical movements that tried to control who could have kids.

Central Nervous System (CNS)

Definition: Brain + spinal cord — main control center.

Example: Sends and receives info for all body actions.

Peripheral Nervous System (PNS)

Definition: All nerves outside the brain/spinal cord.

Example: Connects body to the CNS.

Somatic Nervous System

Definition: processing all sensations. somatic sensory cortex.

Example: Moving your hand to wave.

Autonomic Nervous System

Definition: Controls involuntary actions (heart, breathing, digestion).

Example: Heart beats without thinking.

Sympathetic Nervous System

Definition: “Fight or flight” — prepares body for stress.

Example: Heart races when you’re scared.

Parasympathetic Nervous System

Definition: “Rest and digest” — calms body down.

Example: Slows heart rate after a panic.

Neuron

Definition: Nerve cell that sends and receives signals.

Example: Brain uses billions to think and move.

Glial Cells

Definition: Support and protect neurons.

Example: Like “nurse cells” keeping neurons healthy.

Reflex Arc

Definition: Quick, automatic response handled by spinal cord.

Example: Pulling your hand from a hot stove.

Sensory Neurons

Definition: Carry messages to brain.

Example: Touching ice
→ brain feels cold.

Motor Neurons

Definition: Send brain messages to muscles.

Example: Brain tells legs to run.

Interneurons

Definition: Link sensory and motor neurons.

Example: Brain’s “middle messengers.”

Synapse

Definition: Gap between neurons where messages pass.

Example: Like a bridge for neurotransmitters.

Action Potential

Definition: An electrical signal that travels through a neuron.

Example: The “zap” that fires when you touch something hot.

All-or-Nothing Principle

Definition: A neuron either fires completely or not at all.

Example: You can’t half-send a text; it goes or it doesn’t.

Reuptake

Definition: When neurons reabsorb leftover neurotransmitters.

Example: Recycling signal chemicals after use.

Refractory Period

Definition: Rest time after a neuron fires.

Example: Like waiting a second before sending another text.

Resting Potential

Definition: When a neuron is ready but not firing.

Example: Like a charged battery waiting to be used.

Dopamine

Definition: Linked to pleasure, movement, and learning.

Example: Reward feeling after eating or winning.

Serotonin

Definition: Affects mood, sleep, and hunger.

Example: Low serotonin
→ depression.

Norepinephrine

Definition: A neurotransmitter and hormone that increases alertness, energy, and heart rate during stress or excitement (“fight-or-flight”)

Example: wakes up your body

GABA

Definition: Calms the brain — main inhibitory chemical.

Example: Low GABA
→ anxiety.

Glutamate

Definition: Main excitatory chemical — helps learning & memory.

Example: Too much
→ migraines or seizures.

Acetylcholine

Definition: Helps muscle movement, learning, memory.

Example: Low levels
→ Alzheimer’s.

Endorphins

Definition: Body’s natural painkillers.

Example: Released after exercise (“runner’s high”).

Substance P

Definition: Sends pain signals.

Example: Tells brain “ouch!” when hurt.

Agonist

Definition: Drug that mimics a neurotransmitter.

Example: Nicotine acts like acetylcholine.

Antagonist

Definition: Blocks a neurotransmitter.

Example: Botox blocks ACh, causing muscles to relax.

Reuptake Inhibitor

Definition: Keeps neurotransmitters active longer.

Example: SSRIs block serotonin reuptake to ease depression.

Psychoactive Drugs

Definition: Chemicals that change mood or behavior.

Example: Caffeine, alcohol, or weed.

Stimulants

Definition: Speed up brain activity.

Example: Caffeine, cocaine.

Depressants

Definition: Slow down brain and body.

Example: Alcohol.

Hallucinogens

Definition: Cause distorted perceptions or hallucinations.

Example: LSD, marijuana.

Opioids

Definition: Relieve pain, make you feel relaxed.

Example: Morphine, heroin.

Tolerance

Definition: Needing more of a drug to feel the same effect.

Example: Coffee stops working
→ drink two cups.

Addiction

Definition: Can’t stop using something even if it’s harmful.

Example: Still smoking though you want to quit.

Withdrawal

Definition: Bad symptoms when you stop using a drug.

Example: Headaches after quitting caffeine.

Brain Stem

Definition: Controls basic life functions (breathing, heartbeat).

Example: You stay alive even when asleep.

Medulla

Definition: Controls vital stuff like heart rate & breathing.

Example: Damage here
→ can’t survive.

Retical Formation

Definition: Controls alertness and arousal, helping you stay awake and focused.

Example: keeps you awake.

Cerebellum

Definition: Coordinates balance and movement.

Example: Helps you walk or dance smoothly.

Thalamus

Definition: “Relay station” — sends sensory info to the right brain area.

Example: Directs sights and sounds to the correct lobe.

Hypothalamus

Definition: Regulates hunger, thirst, sleep, body temp, hormones.

Example: Makes you eat when hungry.

Pituitary Gland

Definition: “Master gland” that controls other glands.

Example: Growth hormones.

Limbic System

Definition: Emotion and memory center.

Example: Fear, love, motivation.

Hippocampus

Definition: Forms new memories.

Example: Can’t make new memories if damaged.

Amygdala

Definition: Controls emotions like fear and anger.

Example: Why you jump-scare easily.

Corpus Callosum

Definition: Connects left and right brain halves.

Example: Lets both sides communicate.

Frontal Lobe

Definition: Planning, decisions, personality, movement.

Example: Helps control impulses.

Parietal Lobe

Definition: Processes touch and spatial info.

Example: Knowing where your arm is.

Occipital Lobe

Definition: Handles vision.

Example: Damage
→ vision problems.

Temporal Lobe

Definition: Hearing, memory, and language.

Example: Helps understand what people say.

Motor Cortex

Definition: Controls voluntary movement.

Example: Moves your hand when writing.

Somatosensory Cortex

Definition: Feels touch, pressure, and pain.

Example: Detects your phone’s texture.

Association Areas

Definition: Combine info for learning and thinking from different areas.

Example: Helps you recognize your friend’s face.

Broca’s Area

Definition: brain region that forms words and speak clearly — controls the muscle used for talking

Example: Damage
→ can’t speak clearly.

Wernicke’s Area

Definition: Understands language — both spoken and written.

Example: Damage
→ can speak but words don’t make sense.

Aphasia

Definition: Trouble with speaking or understanding language.

Example: After a stroke, words don’t come out right.

Brain Plasticity

Definition: Brain’s ability to change or heal.

Example: Kids’ brains can relearn lost skills.

Split Brain

Definition: When the corpus callosum is cut, separating communication between the left and right hemispheres(sides of brain)

Example: Helps study left vs. right brain functions.

EEG

Definition: Measures electrical activity or brain waves using electrodes on the scalp.

Example: Used for sleep or seizure studies.

fMRI

Definition: A brain scan that shows active brain areas by tracking blood flow.

Example: See which parts light up during reading.

Lesioning

Definition: when scientists destroy/remove brain tissue to study what that area does

Example: See what happens if a brain part is damaged.

semantic memory

type of long term memory that stores general knowledge “fast based”

example: knowing that the capital of france is paris