AP Psych Unit 3 Terms: Biological Basis of Behavior

Acetylcholine

A neurotransmitter involved in muscle movement and memory.

Action Potential

A rapid change in electrical potential across a neuron's membrane, allowing it to transmit signals.

Adoption Studies

Research examining the influence of genetics versus environment by studying adopted individuals and their biological and adoptive families.

Adrenaline

Hormone and neurotransmitter that plays a key role in the body's stress response, often referred to as the "fight or flight" response.

All-or-Nothing Principle

The principle that a neuron either fires completely or does not fire at all.

Amygdala

A brain structure involved in emotion regulation, particularly fear and pleasure.

Association Areas

Parts of the brain's cerebral cortex that take information from all over the place—like what we see, hear, smell, and touch—and put it together to help us understand the world around us.

Autonomic Nervous System

The part of the nervous system that regulates involuntary bodily functions.

Brainstem

The oldest and most primitive part of the brain, responsible for basic life-sustaining functions such as breathing, heart rate, and sleep-wake cycles.

Broca's Aphasia

A language disorder characterized by difficulty in speech production while comprehension remains intact.

Broca's Area

A region in the frontal lobe associated with speech production.

Central Nervous System

Comprised of the brain and spinal cord; it processes information and coordinates activities.

Cerebellum

A brain structure that coordinates voluntary movements and maintains balance.

Cerebral Cortex

The outer layer of the brain involved in complex functions such as perception, thought, and decision-making.

Corpus Callosum

A bundle of nerve fibers connecting the left and right hemispheres of the brain.

Contralateral Hemispheric Organization

The principle that each hemisphere of the brain controls the opposite side of the body.

Cortex

The outer layer of the brain involved in many higher brain functions.

Depolarization

The process by which a neuron's membrane potential becomes less negative, leading to action potential.

Dopamine

A neurotransmitter involved in reward, motivation, and motor control.

Electroencephalogram (EEG)

A test that measures electrical activity in the brain.

Endorphins

Neurotransmitters that act as natural painkillers and are associated with pleasure.

Eugenics

The belief in improving the genetic quality of a human population by controlling reproduction to increase desirable traits and decrease undesirable ones.

Evolutionary Perspective

A theoretical approach that considers the role of evolution and natural selection in psychological processes.

Excitatory Neurotransmitters

Chemicals that increase the likelihood of a neuron firing.

Executive Functioning

A set of cognitive processes that enable individuals to plan, organize, strategize, focus attention, regulate emotions, and manage time effectively.

Family Studies

Research examining the similarities and differences among family members to assess the influence of genetics and environment.

Frontal Lobes

The part of the brain associated with reasoning, planning, and problem-solving.

Functional Magnetic Resonance Imaging (fMRI)

A technique for measuring brain activity by detecting changes in blood flow.

GABA

A neurotransmitter that acts as the primary inhibitory neurotransmitter in the central nervous system. It promotes relaxation and reduces anxiety.

Genetic Predisposition

An inherited tendency to develop certain traits or disorders.

Ghrelin

Hormone produced primarily by the stomach and small intestine that stimulates appetite and promotes hunger.

Glial Cells

Supportive cells in the nervous system that assist neurons.

Glutamate

The main excitatory neurotransmitter in the brain.

Hemispheric Specialization

The idea that different brain hemispheres have specialized functions.

Heredity

The transmission of genetic characteristics from parents to offspring.

Hippocampus

A brain structure involved in memory formation and spatial navigation.

Hormones

Chemical messengers that regulate various bodily functions, produced by glands.

Hypothalamus

A brain region involved in regulating bodily functions such as temperature and hunger.

Inhibitory Neurotransmitters

Chemicals that decrease the likelihood of a neuron firing.

Interneurons

Neurons that connect other neurons within the brain and spinal cord.

Leptin

Hormone produced primarily by fat cells that regulates energy balance and appetite. It acts on the hypothalamus in the brain to suppress appetite and increase energy expenditure.

Lesioning

The process of damaging a specific area of the brain to study its function.

Limbic System

A group of structures in the brain involved in emotion and memory.

Linguistic Processing

The complex cognitive processes involved in understanding and producing language.

Lobes of the Brain

Major regions of the cerebral cortex (frontal, parietal, occipital, temporal).

Medulla

The brainstem structure responsible for vital functions like heart rate and breathing.

Melatonin

A hormone that regulates sleep-wake cycles.

Motor Cortex

A region of the brain involved in planning and executing voluntary movements.

Motor Neurons

Neurons that transmit signals to muscles, enabling movement.

Multiple Sclerosis (MS)

A chronic disease affecting the central nervous system, characterized by damage to the myelin sheath.

Myasthenia Gravis

An autoimmune disorder that affects communication between nerves and muscles, leading to weakness.

Natural Selection

The process by which organisms with traits that are better suited to their environment are more likely to survive and reproduce, passing on those advantageous traits to future generations.

Nature

The influence of genetic factors on behavior and traits.

Neurons

The basic building blocks of the nervous system that transmit information.

Neurotransmitters

Chemical messengers that transmit signals between neurons.

Nervous System

The network of nerve cells and fibers that transmits nerve impulses throughout the body.

Norepinephrine

A neurotransmitter involved in arousal and alertness.

Nurture

The influence of environmental factors on behavior and traits.

Occipital Lobes

The regions of the brain responsible for processing visual information.

Oxytocin

A hormone involved in social bonding and reproduction.

Parasympathetic Nervous System

The part of the autonomic nervous system that promotes relaxation and energy conservation.

Parietal Lobes

Located at the top of the brain and are primarily responsible for processing sensory information from the body, such as touch, temperature, and spatial awareness.

Peripheral Nervous System

The portion of the nervous system outside the brain and spinal cord.

Plasticity

The brain's ability to adapt and reorganize itself in response to experience or injury.

Pituitary Gland

The "master gland" that regulates other endocrine glands and hormone release.

Prefrontal Cortex

The area of the frontal lobe involved in complex cognitive behavior and decision-making.

Reflex Arc

The neural pathway that controls a reflex action.

Refractory Period

The time following an action potential during which a neuron cannot fire again.

Reticular Activating System

A network of neurons in the brainstem that regulates wakefulness and sleep-wake transitions.

Resting Potential

The electrical potential of a neuron at rest, when it is not transmitting signals.

Reuptake

The process by which neurotransmitters are reabsorbed into the presynaptic neuron after transmission.

Reward Center

Areas in the brain involved in reinforcing behaviors that provide pleasure.

Sensory Neurons

Specialized nerve cells that transmit sensory information from sensory receptors, such as those in the skin, muscles, and organs, to the central nervous system (brain and spinal cord).

Serotonin

neurotransmitter that plays a vital role in regulating mood, sleep, appetite, and stress.

Somatic Nervous System

The part of the peripheral nervous system that controls voluntary movements.

Somatosensory Cortex

A region of the brain that processes sensory information from the body.

Split Brain Research

Studies that examine the effects of severing the corpus callosum on cognitive functioning.

Substance P

A neurotransmitter involved in pain perception.

Sympathetic Nervous System

The part of the autonomic nervous system responsible for the body's "fight or flight" response.

Temporal Lobes

Regions of the brain involved in processing auditory information and memory.

Thalamus

A brain structure that relays sensory and motor signals to the cerebral cortex.

Threshold

The minimum level of stimulation required to trigger an action potential in a neuron.

Twin Studies

Research involving twins to study the relative contributions of genetics and environment to behavior.

Wernicke's Aphasia

Language disorder caused by damage to Wernicke's area in the left hemisphere of the brain, typically resulting from stroke or brain injury.

Wernicke's Area

Region located in the left hemisphere of the brain, specifically in the temporal lobe, that is involved in language comprehension and understanding spoken and written language.

Computerized axial tomography (CAT or CT)

creates a computerized image using X-rays passed through various angles of the brain showing two-dimensional “slices” that can be arranged to show the extent of a lesion

Positron emission tomography (PET)

produces color computer graphics that depend on the amount of metabolic activity in the imaged brain region

dendrites

are branching tubular processes capable of receiving information

Antagonists

block a receptor site, inhibiting the effect of the neurotransmitter or agonist

Agonists

may mimic a neurotransmitter and bind to its receptor site to produce the effect of the neurotransmitter

Circadian rhythm

• is a natural, internal process that regulates the sleep-wake cycle and repeats roughly every 24 hours.

  • It's also known as your body’s clock — it influences when you fall asleep and wake up.

  • Your circadian rhythm mainly responds to light and darkness in your environment.