AP Psych- Vocab unit 3

Neuron

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

Synapse

The junction where one neuron communicates with another neuron, muscle, or gland.

Synaptic gap

The tiny space between neurons that neurotransmitters cross.

Axon

The part of a neuron that carries neural messages away from the cell body.

Dendrites

Branching parts of a neuron that receive messages and carry them toward the cell body.

Threshold

The minimum level of stimulation needed to trigger a neural impulse.

Neurotransmission

The process of neurons communicating by sending electrical and chemical signals.

Resting potential

The neuron's inactive state when it is ready to fire.

All-or-none principle

A neuron either fires completely or does not fire at all.

Depolarization

The change in a neuron's electrical charge that occurs when it becomes less negative as positive ions enter.

Myelin sheath

A fatty covering around the axon that insulates it and speeds neural transmission.

Glial cells

Cells that support, nourish, protect, and maintain neurons.

Refractory period

The brief period after a neuron fires when it cannot immediately fire again.

Action potential

A brief electrical impulse that travels down the axon.

Nervous system

The body's communication system that receives, processes, and sends information.

Sensory neurons

Neurons that carry sensory information toward the brain and spinal cord.

Motor neurons

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

Reflex arcs

Simple, automatic neural pathways that produce quick responses to stimuli.

Interneurons

Neurons in the CNS that connect and communicate between other neurons, such as sensory and motor neurons.

CNS

Central nervous system; the brain and spinal cord.

PNS

Peripheral nervous system; all nerves outside the brain and spinal cord.

SNS

Somatic nervous system; controls voluntary movements of skeletal muscles.

ANS

Autonomic nervous system; controls glands and internal organs automatically.

Sympathetic NS

The autonomic division that arouses the body and mobilizes energy during stress.

Parasympathetic NS

The autonomic division that calms the body and conserves energy after stress.

Neurotransmitter

A chemical messenger that crosses the synaptic gap and communicates with another cell.

Reuptake

The process of a neuron reabsorbing excess neurotransmitters from the synaptic gap.

Excitatory

An effect that increases the likelihood that a neuron will fire.

Inhibitory

An effect that decreases the likelihood that a neuron will fire.

Dopamine

A neurotransmitter involved in movement, learning, attention, emotion, and reward; low levels are linked to Parkinson's and excess activity is linked to schizophrenia.

Serotonin

A neurotransmitter involved in mood, hunger, sleep, arousal, and appetite; low levels are linked to depression.

Norepinephrine

A neurotransmitter involved in alertness and arousal; low levels can depress mood.

Glutamate

A major excitatory neurotransmitter involved in memory; too much can overstimulate the brain and contribute to migraines or seizures.

GABA

A major inhibitory neurotransmitter; low levels are associated with seizures, tremors, and insomnia.

Endorphins

Natural opiate-like neurotransmitters that reduce pain and can produce pleasure and a runner's high.

Substance P

A neurotransmitter involved in transmitting pain signals.

Endocrine system

The body's slow chemical communication system that uses glands to release hormones into the bloodstream.

Hormones

Chemical messengers released by endocrine glands that travel through the bloodstream and affect other tissues.

Adrenaline

Also called epinephrine; a hormone and neurotransmitter that activates the sympathetic fight-or-flight response.

Adrenal glands

Glands located on top of the kidneys that release hormones such as adrenaline.

Melatonin

A hormone that regulates the body's approximately 24-hour sleep-wake cycle, or circadian rhythm.

Oxytocin

A hormone and neurotransmitter involved in social bonding, trust, attachment, and connection.

Ghrelin

A hormone released by an empty stomach that signals hunger and stimulates appetite.

Leptin

A hormone released by fat cells that signals fullness and decreases hunger.

Pituitary gland

An endocrine gland controlled by the hypothalamus that helps regulate other endocrine glands.

Alzheimer's disease

A disease involving brain deterioration and memory loss; associated with deterioration of acetylcholine-producing neurons.

Parkinson's disease

A disorder associated with low dopamine and characterized by symptoms such as tremors and decreased mobility.

Broca's area

A region of the frontal lobe involved in producing speech.

Broca's aphasia

Difficulty producing speech caused by damage to Broca's area.

Split brain

A condition in which the corpus callosum is severed or disrupted, limiting communication between the two hemispheres.

Contralaterality

The principle that each brain hemisphere generally controls or receives information from the opposite side of the body.

Plasticity

The brain's ability to reorganize and change, especially after damage.

Aphasia

Impaired ability to use or understand language due to brain damage.

Amygdala

A limbic system structure involved in emotions such as fear and aggression.

Cerebellum

The brain structure that coordinates voluntary movement, balance, and coordination.

Brainstem/medulla

contains structures involved in basic life functions; the medulla helps regulate breathing and heartbeat.

Cerebral cortex

The outer layer of the brain involved in complex thought, information processing, and control of behavior.

Hippocampus

A limbic system structure involved in memory.

Hypothalamus

A brain structure that regulates basic drives and homeostasis and controls the pituitary gland.

Limbic system

A group of brain structures involved in emotion and basic drives such as hunger, sex, fear, and aggression.

Hemispheric specialization

The idea that the two brain hemispheres have different specialized functions.

Wernicke's area

A brain area involved in understanding language and meaning.

Motor cortex

The area of the frontal lobe that controls voluntary movement.

Sensory cortex

The area of the parietal lobe that processes touch and other body sensations.

Dual processing

The brain's ability to process information simultaneously on conscious and unconscious levels.

Lesioning

Studying brain function by damaging a specific brain area and observing the effects.

Parietal lobes

Brain lobes involved in processing sensory information, especially touch.

Temporal lobes

Brain lobes involved in hearing, language, memory, and processing sounds.

Occipital lobe

The brain lobe at the back of the brain that processes visual information.

Phantom limb syndrome

The sensation that an amputated limb is still present, sometimes including pain or other sensations.

MRI

Magnetic Resonance Imaging; produces detailed images of brain structure using magnetic fields and radio waves.

fMRI

Functional MRI; shows brain activity by measuring changes in blood flow.

EEG

Electroencephalogram; records the brain's electrical activity and brain-wave patterns.

PET scan

A brain scan that shows activity by tracking the brain's use of glucose.

CT scan

A scan that creates detailed images of the brain and skull but does not show brain function.

Cognition

Mental processes involved in thinking, knowing, remembering, understanding, and problem-solving.

Cognitive psychologist

A psychologist who studies mental processes such as thinking, memory, perception, and language.

Agonists

Drugs or chemicals that increase or activate a neurotransmitter's effects.

Antagonists

Drugs or chemicals that block or decrease a neurotransmitter's effects.

Knee jerk reflex

An automatic reflex in which tapping the patellar tendon causes the lower leg to kick forward.

Reward system in animals and humans

A brain network involved in pleasure, motivation, and reinforcement.

Right/left sides of brain

The left hemisphere is more specialized for language, reading, writing, and arithmetic, while the right is more involved in nonverbal, visual, artistic, and creative functions.

Lateralization

The specialization of certain functions in the left or right hemisphere of the brain.