AP Psychology Unit 2 Vocabulary - Biological Bases of Behavior

Comprehensive vocabulary flashcard set covering biological psychology, nervous system structures, neural communication, endocrine system, brain regions, neuroimaging, and psychoactive drugs.

epigenetics

The study of environmental influences on gene expression that occur without a DNA change.

nervous system

The body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems.

central nervous system (CNS)

The brain and spinal cord.

peripheral nervous system (PNS)

The sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.

nerves

Bundled axons that form neural cables connecting the central nervous system with muscles, glands, and sense organs.

sensory (afferent) neurons

Neurons that carry incoming information from the body's tissues and sensory receptors to the brain and spinal cord.

motor (efferent) neurons

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

interneurons

Neurons within the brain and spinal cord that communicate internally and process information between sensory inputs and motor outputs.

somatic nervous system

The division of the peripheral nervous system that controls the body's skeletal muscles.

autonomic [aw-tuh-NAHM-ik] nervous system (ANS)

The part of the peripheral nervous system that controls the glands and the muscles of internal organs.

sympathetic nervous system

The division of the autonomic nervous system that arouses the body, mobilizing its energy.

parasympathetic nervous system

The division of the autonomic nervous system that calms the body, conserving its energy.

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

dendrites

A neuron's often bushy, branching extensions that receive and integrate messages, conducting impulses toward the cell body.

axon

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

myelin [MY-uh-lin] sheath

A fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed as neural impulses hop from one node to the next.

glial cells (glia)

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

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 resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state.

all-or-none response

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

synapse [SIN-aps]

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

neurotransmitters

Chemical messengers that cross the synaptic gaps between neurons.

reuptake

A neurotransmitter's reabsorption by the sending neuron.

endorphins [en-DOR-fins]

'Morphine within'—natural, opiate-like neurotransmitters linked to pain control and to pleasure.

agonist

A molecule that increases a neurotransmitter's action.

antagonist

A molecule that inhibits or blocks a neurotransmitter's action.

endocrine [EN-duh-krin] system

The body's 'slow' chemical communication system; a set of glands that secrete hormones into the bloodstream.

hormones

Chemical messengers that are manufactured by the endocrine glands, 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 and/or physical risk.

depressants

Drugs (such as alcohol, barbiturates, and opiates) that reduce neural activity and slow body functions.

tolerance

The diminishing effect with regular use of the same dose of a drug, requiring the user to take larger and larger doses before experiencing the drug's effect.

addiction

A primary, chronic disease of brain reward, motivation, memory, and related circuitry marked by compulsive craving and use of a substance or behavior despite adverse consequences.

withdrawal

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

barbiturates

Drugs that depress central nervous system activity, reducing anxiety but impairing memory and judgment.

opioids

Opium and its derivatives (such as morphine and heroin); depress neural activity, temporarily lessening pain and anxiety.

stimulants

Drugs (such as caffeine, nicotine, and the more powerful cocaine, amphetamines, methamphetamine, and Ecstasy) that excite neural activity and speed up body functions.

hallucinogens

Psychedelic ('mind-manifesting') drugs, such as LSD, that distort perceptions and evoke sensory images in the absence of sensory input.

near-death experience

An altered state of consciousness reported after a close brush with death; often similar to drug-induced hallucinations.

biological psychology

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

biopsychosocial approach

An integrated approach that incorporates biological, psychological, and social-cultural levels of analysis.

levels of analysis

The differing complementary views, from biological to psychological to social-cultural, for analyzing any given phenomenon.

neuroplasticity

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

lesion [LEE-zhuhn]

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

EEG (electroencephalogram)

An amplified recording of the waves of electrical activity sweeping across the brain's surface; measured by electrodes placed on the scalp.

MEG (magnetoencephalography)

A brain imaging technique that measures magnetic fields from the brain's natural electrical activity.

CT (computed tomography) scan

A series of X-ray photographs taken from different angles and combined by computer into a composite representation of a slice of the brain's structure.

PET (positron emission tomography)

A 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)

A technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue, showing brain structure.

fMRI (functional MRI)

A technique for revealing bloodflow and, therefore, brain activity by comparing successive MRI scans; shows brain function as well as structure.

hindbrain

The lower part of the brainstem, comprising the cerebellum, pons, and medulla oblongata.

midbrain

A small part of the brain above the pons that integrates sensory information and relays it upward.

forebrain

The largest and most complicated region of the brain, including the thalamus, hypothalamus, limbic system, and cerebrum.

brainstem

The oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; responsible for automatic survival functions.

medulla [muh-DUL-uh]

The base of the brainstem; controls heartbeat and breathing.

thalamus [THAL-uh-muss]

The brain's sensory control center, located on top of the brainstem; directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla.

reticular formation

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

cerebellum [sehr-uh-BELL-um]

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.

limbic system

Neural system (including the amygdala, hypothalamus, and hippocampus) located below the cerebral hemispheres; associated with emotions and drives.

amygdala [uh-MIG-duh-la]

Two lima-bean-sized neural clusters in the limbic system; linked to emotion, particularly fear and aggression.

hypothalamus [hi-po-THAL-uh-muss]

A neural structure lying below the thalamus; directs maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward.

hippocampus

A neural center located in the limbic system; helps process explicit (conscious) memories for storage.

cerebral [seh-REE-bruhl] cortex

The intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body's ultimate control and information-processing center.

frontal lobes

Portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgments.

parietal [puh-RYE-uh-tuhl] lobes

Portion of the cerebral cortex lying at the top of the head and toward the rear; receives sensory input for touch and body position.

occipital [ahk-SIP-uh-tuhl] lobes

Portion of the cerebral cortex lying at the back of the head; includes areas that receive information from the visual fields.

temporal lobes

Portion of the cerebral cortex lying roughly above the ears; includes the 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.

association areas

Areas of the cerebral cortex that are not involved in primary motor or sensory functions; involved in higher mental functions such as learning, remembering, thinking, and speaking.

neurogenesis

The formation of new neurons.

corpus callosum

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