AP Psych Unit 1

nature-nurture

Debate over the relative influence of genes (nature) and environment (nurture).

charles darwin

A British naturalist who developed the theory of evolution by natural selection.

behavior genetics

The field of study that examines the relationship between genetic variation and psychological traits to understand how heredity and environment influence behavior.

mutation

A change in the DNA sequence of a gene.

environment

All non-genetic influences.

heredity

The passing of genetic info and traits from parents to their offspring.

genes

The fundamental physical and functional units of heredity, consisting of specific sequences of DNA.

genome

The complete set of DNA instructions found in a cell or organism.

identical (monozygotic) twins

Twins who develop from a single fertilized egg that splits in two.

fraternal (dizygotic) twins

Twins who develop from two separate fertilized eggs.

interaction

When the effect of one factor (environment) depends on another factor (heredity).

epigenetics

How environmental factors and behaviors can cause stable, heritable changes in gene expression without altering the underlying DNA sequence.

nervous system

The body's electrochemical communication network, including the brain, spinal cord, and all the nerves.

central nervous system (CNS)

The brain and spinal cord, which act as the body's command center.

peripheral nervous system (PNS)

All the nerves extending from the brain and spinal cord that connect the CNS to the rest of the body.

nerves

Bundles of axons that form neural "cables" connecting the CNS with muscles, glands, and sense organs.

sensory (afferent) neurons

Neurons that carry incoming info from the body's sensory receptors to the CNS.

motor (efferent) neurons

Neurons that carry outgoing info from the CNS to the muscles and glands.

interneurons

Neurons within the CNS that communicate internally between the sensory inputs and motor outputs.

somatic nervous system

The division of the PNS that controls the body's skeletal muscles and voluntary movements.

autonomic nervous system (ANS)

The division of the PNS that controls the glands and internal organs, like the heartbeat.

sympathetic nervous system

The division of the ANS that arouses the body, mobilizing its energy during "fight-or-flight".

parasympathetic nervous system

The division of the ANS that calms the body, conserving its energy.

neuron

A basic nerve cell and the fundamental building block of the nervous system.

cell body

The part of a neuron that contains the nucleus; the cell's life-support center.

dendrites

Bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body.

axon

The long, nerve fiber extension of a neuron that passes messages from the cell body to other neurons, muscles, or glands.

myelin sheath

A layer of fatty tissue that insulates the axons of some neurons, enabling faster transmission of neural impulses.

glial cells (glia) 

"Support" cells that protect, nourish, and assist neurons.

sensory neuron

Nerve cell that transmits info from sensory receptors to the CNS, letting you perceive and respond to environment.

motor neuron

Nerve cells that carry signals from the CNS to your muscles and glands, triggering response.

interneurons

Nerve cells in CNS, relaying signals between sensory neurons and motor neurons to facilitate info processing and complex behaviors.

action potential

A brief electrical charge that travels down an axon, caused by the movement of positively charged atoms in and out of channels in the axon's membrane.

all-or-nothing principle

Neurons either fully fired or not at all.

depolarization

Process where a neuron's internal charge becomes less negative (more positive) due to the influx of positive ions, such as sodium (Na+) ions.

refractory period

A brief period of inactivity after a neuron has fired, during which it cannot fire again.

synapse

The junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron.

neurotransmitters

Chemical messengers that travel across the synaptic gaps between neurons.

reuptake

The process by which a sending neuron reabsorbs excess neurotransmitters from the synaptic gap.

endorphins

natural neurotransmitters linked to pain control and pleasure.

agonist

A molecule activates receptor.

antagonist

A molecule blocks reeceptor.

multiple sclerosis

A neurological disease that involves the autoimmune destruction of the myelin sheath.

dopamine

Neurotransmitter, chemical messenger in brain. Memory, sleep, mood, pleasurable reward, behavior, and cognition.

norepinephrine

Neurotransmitter and hormone in the "fight-or-flight" by increasing alertness.

GABA

Inhibitory neurotransmitter in the CNS in regulating brain activity, anxiety, and stress.

substance p

Neuropeptide that functions as a neurotransmitter in transmitting pain signals from the body to the brain.

leptin

a satiety hormone secreted by fat cells that signals the brain, specifically the hypothalamus, to reduce hunger and increase metabolism

melatonin

Hormone produced by the pineal gland that regulates circadian rhythm by signaling time to sleep.

resting potential

the stable electrical charge across a neuron's cell membrane when it is not actively sending an impulse or signal

myasthenia gravis

AID that affects the neuromuscular junction, the point where nerves meet muscles. 

inhibitory neurotransmitters

Chemical messenger that reduces likelihood neuron firing an action potential by causing hyperpolarization.

serotonin

Neurotransmitter that plays a crucial role in regulating mood, emotion, and behavior.

glutamate

Major excitatory neurotransmitter in CNS, in learning and memory by increasing the likelihood of a neuron firing

acetylcholine

Neurotransmitter in enabling muscle action, as well as in learning and memory formation

endocrine system

Body's slow chemical comm., glands that exit hormones into the bloodstream.

adrenaline

Hormone released by the adrenal glands in response to a stress

ghrelin

Hormone produced in the stomach that acts as a hunger stimulant

oxytocin

Hormone and neurotransmitter in social bonding, reproduction, and childbirth.

psychoactive drug

Chemical substance that alters perceptions and moods.

substance use disorder

Continued substance use despite bad.

stimulant

Drugs that excite (caffeine, nicotine, amphetamines)

reuptake inhibitor

Drug that blocks the neurotransmitter from being reabsorbed by the sending neuron, increasing the neurotransmitter's presence in the synaptic cleft and enhancing its signaling effect

depressants

Drugs that calm (alcohol, barbiturates, opioids).

barbiturates

Drugs that depress CNS, induce sleep or reduce anxiety.

hallucinogens

Psychedelic drugs (LSD) that distort perceptions and evoke sensory images

opioids

Drugs (morphine and heroin) that depress neural activity, less pain and anxiety.

neuroplasticity

The brain's ability to change, especially during childhood, by reorganizing after damage or building new pathways based on experience.

EEG (electroencephalogram)

Recording of the waves of electrical activity sweeping across the brain's surface.

MEG (magnetoencephalography)

Brain-imaging technique that measures magnetic fields from the brain's natural electrical currents.

CT (computed tomography) scan

Series of X-ray photographs taken from different angles and combined by computer into a composite representation of a slice of the brain

PET (positron emission tomography) scan

Visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task

MRI (magnetic resonance imaging)

Uses magnetic fields and radio waves to produce computer-generated images of soft tissue

fMRI (functional MRI)

Technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans

lesion

A naturally or experimentally caused destruction of brain tissue to examine

medulla oblongata

Base of the brainstem that controls vital, involuntary survival functions

reticular activating system (RAS)

Nerve network that runs through the brainstem and helps regulate alertness, arousal, and attention

cerebellum

Located at the rear of the brainstem, for coordinating voluntary movement, posture, balance, and fine motor skills

cerebral cortex

The thin, outer layer of the cerebrum, for higher-level mental functions.

limbic system

A group of neural structures associated with emotions (like fear and aggression), motivation, and memory formation.

thalamus

brain's "sensory control center" or "relay station," it receives most sensory info (except smell) and directs it to the appropriate areas of the cortex.

hypothalamus

below the thalamus, regulates maintenance, controls endocrine system via the pituitary gland.

pituitary gland

"master gland," it is controlled by the hypothalamus. It regulates growth and controls other endocrine glands.

hippocampus

structure in the limbic system, processing and forming new explicit (conscious) memories for long-term storage.

amygdala

Two almond-shaped neural clusters in the limbic system, linked to emotion, especially fear and aggression.

corpus callosum

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

split brain

A condition resulting from surgery that isolates the two hemispheres by cutting the corpus callosum.

broca’s area

A region in the left frontal lobe that is responsible for speech production. Damage → impair speaking.

wernicke’s area

A region, typically in the left temporal lobe, that is vital for language comprehension. Damage → difficulty understanding language. 

cortex specialization

The principle that specific areas of the brain's cortex are dedicated to specialized functions.

contralateral hemispheric organization

The left hemisphere of the brain controls the right side of the body, and the right hemisphere controls the left side of the body.

aphasia

Impairment of language, which can occur as a result of damage to any of several cortical areas, including Broca's and Wernicke's areas.

occipital lobe

Located at the back of the head, it receives and processes visual info.

temporal lobe

Positioned just above the ears, it includes the auditory areas that process sound info.

parietal lobe

top of the head towards the rear, it processes sensory input for touch and body position.

somatosensory cortex

A strip of the parietal lobe that receives and processes info from skin senses and body parts.

frontal lobe

The front-most part of the cerebral cortex, it is involved in speaking, muscle movements, planning, and judgment.

prefrontal cortex

The very front of the frontal lobe, associated with executive functions such as planning, decision-making, and social behavior.

motor cortex

A strip of the frontal lobe, located at the back, that controls voluntary movements. 

association areas

Areas involved in higher mental functions like learning, remembering, thinking, and speaking.