AP Psych Test

Biological Psychology

The scientific study of the links between biological (genetic, neural, hormonal) and psychological processes

Neuron

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

Dendrites

A neuron’s bushy, branching extensions that receive messages and conduct impulses toward the cell body (soma)

Axon

The neuron extension that passes messages through its branches to other neurons, muscles, or glands

Myelin Sheath

A fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed of neural impulses

Action Potential

A neural impulse; a brief electrical charge that travels down an axon. Caused by the movement of positively charged ions across the membrane

Resting Potential

The fluid interior of a resting axon has a negative charge, while the fluid exterior has a positive charge (polarized state)

Refractory Period

A period of inactivity after a neuron has fired during which the neuron pumps positive ions back outside to reset (repolarize)

Threshold

The level of stimulation required to trigger a neural impulse

All-or-None Response

A neuron's reaction of either firing (with a full-strength response) or not firing at all

Synapse

The junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron (separated by the synaptic gap/cleft)

Neurotransmitters

Chemical messengers that cross the synaptic gaps between neurons to bind to receptor sites on the receiving neuron

Reuptake

A neurotransmitter’s reabsorption by the sending neuron

Agonist

A molecule that increases a neurotransmitter's action by binding to a receptor site and mimicking its effects or blocking reuptake

Antagonist

A molecule that inhibits or blocks a neurotransmitter's action by binding to receptor sites without activating them

Acetylcholine (ACh)

Function: Enables muscle action, learning, and memory.

Malfunction: Deterioration of ACh-producing neurons is linked to Alzheimer's disease

Dopamine

Function: Influences movement, learning, attention, and emotion.

Malfunction: Oversupply is linked to schizophrenia; undersupply is linked to tremors and loss of motor control in Parkinson's disease

Serotonin

Function: Affects mood, hunger, sleep, and arousal.

Malfunction: Undersupply is linked to depression

Endorphins

Function: "Morphine within"—natural, opiate-like neurotransmitters linked to pain control and pleasure

Substance P

Function: A neurotransmitter involved in transmitting pain signals to the central nervous system

GABA

Gamma-aminobutyric acid): Major inhibitory neurotransmitter. Undersupply linked to seizures, tremors, and insomnia

Glutamate

Major excitatory neurotransmitter involved in memory. Oversupply can overstimulate the brain, producing migraines or seizures

Sensory Neurons (Afferent)

Neurons that carry incoming information from the sensory receptors to the brain and spinal cord (Afferent = Arriving at CNS)

Motor Neurons (Efferent)

Neurons that carry outgoing information from the brain and spinal cord to the muscles and glands (Efferent = Exiting CNS)

Interneurons

Neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs

Somatic Nervous System

Division of the peripheral nervous system (PNS) that controls the body's skeletal muscles (voluntary control)

Autonomic Nervous System

Division of the PNS that controls the glands and muscles of internal organs (involuntary control)

Sympathetic Nervous System

Division of the ANS that arouses the body, mobilizing its energy in stressful situations ("fight or flight")

Parasympathetic Nervous System

Division of the ANS that calms the body, conserving its energy ("rest and digest")

Medulla

Controls heartbeat and breathing

Pons

Helps coordinate movement and controls sleep

Reticular Formation

A nerve network that travels through the brainstem and thalamus; plays an important role in controlling arousal and awareness

Thalamus

The brain's sensory control center (located at the top of the brainstem). Directs messages to the sensory receiving areas in the cortex (relays all senses except smell)

Cerebellum

The "little brain" at the rear of the brainstem. Functions include processing sensory input, coordinating movement output and balance, and enabling nonverbal learning and memory

Amygdala

Two lima-bean-sized neural clusters; linked to emotion, particularly fear and aggression

Hippocampus

Directs maintenance activities (eating, drinking, body temperature) and governs the endocrine system via the pituitary gland. Linked to emotion and reward

Pituitary Gland

The endocrine system's "master gland," regulated by the hypothalamus; releases growth hormone and oxytocin

Frontal Lobes

Involved in speaking, muscle movements, making plans, and judgments

Parietal Lobes

Receives sensory input for touch and body position

Occipital Lobes

Includes areas that receive information from the visual fields

Temporal Lobes

Includes auditory areas, each receiving information primarily from the opposite ear

Motor Cortex

An area at the rear of the frontal lobes that controls voluntary movements

Somatosensory Cortex

An area at the front of the parietal lobes that registers and processes body touch and movement sensations

Broca's Area

Controls language expression; an area in the left frontal lobe that directs muscle movements involved in speech production

Wernicke's Area

Controls language reception/comprehension; a brain area in the left temporal lobe involved in language comprehension

Neuroplasticity

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

Neurogenesis

The formation of new neurons

Split-Brain Operation

A condition resulting from surgery that isolates the brain's two hemispheres by cutting the corpus callosum (the band of axon fibers connecting them). Used historically to control severe epileptic seizures.

Left Hemisphere

Dominant for language, logic, calculation, and sequential processing

Right Hemisphere

Dominant for spatial perception, visual recognition (faces), inferences, and emotion recognition

Excitatory v. Inhibitory Impulse

Excitatory signals push a neuron’s accelerator to fire an action potential; inhibitory signals push the brake to prevent firing

Glial cells

Cells in the nervous system that support, nourish, and protect neurons; they also play a role in learning and thinking

Neural networks

Interconnected clusters of neurons in the brain that work together to process info and build complex skills

EEG

Records electrical waves

PET

measures radioactive glucose consumption

MRI

uses magnetic fields for structural images

fMRI

shows both structure and blood flow (function)

Cerebral cortex

the intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body’s ultimate control & info-processing center

Association areas

areas of the cerebral cortex not involved in primary motor or sensory functions; involved in higher mental functions like learning, remembering, thinking, and speaking

Corpus callosum

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

Nature v. Nuture

the long-standing controversy over the relative contributions that genes (nature) and experience (nuture) make to the development of psychological traits and behaviors