AP Psych Unit 1: Biological Bases of Behavior

A complete set of vocabulary flashcards covering neural communication, neurotransmitters, disorders, brain anatomy, nervous system divisions, and the endocrine system for AP Psychology Unit 1.

Neuron

A nerve cell that receives and transmits information through electrical and chemical signals, serving as the basic building block of the nervous system.

Glial Cells

Cells that support, nourish, protect, and insulate neurons, while also assisting with neural communication and waste removal.

Sensory Neurons

Neurons that carry incoming information from sensory receptors to the brain and spinal cord.

Motor Neurons

Neurons that carry outgoing information from the brain and spinal cord to muscles and glands, allowing movement and other responses.

Interneurons

Neurons located within the brain and spinal cord that process information and communicate between sensory and motor neurons.

All-or-Nothing Principle

The principle that a neuron either fires a complete action potential or does not fire at all; a stronger stimulus does not create a stronger action potential.

Depolarization

The process in which the inside of a neuron becomes less negative (more positive), usually as positively charged sodium ions enter the cell.

Action Potential

A brief electrical impulse that travels down a neuron's axon, allowing it to transmit information.

Refractory Period

A short period after a neuron fires during which it cannot immediately fire another action potential or requires a stronger stimulus to fire again.

Resting Potential

The electrical charge difference across a neuron's membrane when it is not firing, where the inside is more negatively charged than the outside, typically around $-70\text{ millivolts}$.

Reuptake

The process in which neurotransmitters are reabsorbed by the sending neuron after being released into the synapse.

Threshold

The minimum level of stimulation needed to trigger an action potential.

Neurotransmitter

A chemical messenger that carries signals between neurons across a synapse, or from neurons to other target cells.

Excitatory Neurotransmitter

A neurotransmitter that increases the likelihood that the receiving neuron will fire an action potential.

Inhibitory Neurotransmitter

A neurotransmitter that decreases the likelihood that the receiving neuron will fire an action potential.

Agonist

A substance that mimics or increases the effects of a neurotransmitter by activating its receptors or enhancing its activity.

Antagonist

A substance that blocks or reduces the effects of a neurotransmitter, often by preventing it from activating its receptors.

Acetylcholine (ACh)

A neurotransmitter involved in muscle contractions, learning, and memory; reduced acetylcholine activity is associated with Alzheimer's disease.

GABA (Gamma-Aminobutyric Acid)

The brain's major inhibitory neurotransmitter that reduces neural activity and helps regulate anxiety, sleep, and relaxation.

Serotonin

A neurotransmitter involved in mood, sleep, appetite, and emotional regulation; altered serotonin signaling is associated with depression and other mood disorders.

Dopamine

A neurotransmitter involved in reward, motivation, pleasure, learning, and movement; reduced activity is linked to Parkinson's disease, and abnormal signaling is implicated in schizophrenia.

Norepinephrine

A neurotransmitter involved in alertness, arousal, attention, and the body's response to stress; reduced activity in some pathways is associated with depression.

Glutamate

The brain's major excitatory neurotransmitter involved in learning and memory; excessive activity can contribute to seizures and neuron damage.

Substance P

A neurotransmitter and neuropeptide involved in transmitting pain signals and regulating inflammation.

Endorphins

Natural chemicals produced by the body that reduce pain and produce feelings of pleasure or well-being, often associated with a "runner's high."

Multiple Sclerosis (MS)

A disease in which the immune system damages the myelin sheath surrounding nerve fibers in the central nervous system, disrupting neural communication.

Myasthenia Gravis

An autoimmune disorder in which antibodies interfere with communication between nerves and muscles, usually by attacking acetylcholine receptors, causing muscle weakness and fatigue.

Lesion

An area of damaged or destroyed brain tissue studied by scientists to understand the functions of different brain regions.

fMRI (Functional Magnetic Resonance Imaging)

A brain-imaging technique that measures changes in blood oxygen levels to estimate brain activity during particular tasks.

EEG (Electroencephalogram)

A technique that records electrical activity in the brain using scalp electrodes, commonly used to study sleep stages, seizures, and brain-wave patterns.

Medulla

A structure in the brainstem that controls essential automatic life-sustaining functions such as breathing, heart rate, and swallowing.

Reticular Activating System (RAS)

A network of neurons in the brainstem that regulates alertness, arousal, attention, and the sleep-wake cycle, and helps filter incoming sensory information.

Cerebellum

A brain structure located near the back of the brain that coordinates balance, posture, voluntary movements, and motor learning.

Limbic System

A group of interconnected brain structures involved in emotion, motivation, memory, and basic drives, including the amygdala, hippocampus, and hypothalamus.

Thalamus

The brain's major sensory relay station that directs most incoming sensory information to appropriate areas of the cerebral cortex, excluding smell.

Hypothalamus

A small brain structure that maintains homeostasis by regulating hunger, thirst, and body temperature, while controlling the pituitary gland and endocrine system.

Hippocampus

A brain structure involved in forming and consolidating new explicit memories, including facts and personal experiences, as well as spatial navigation.

Amygdala

A brain structure involved in processing emotions, particularly fear, threat detection, and aggression, and helping form emotional memories.

Plasticity (Neuroplasticity)

The brain's ability to change, reorganize, and form new neural connections in response to learning, experiences, or injury.

Frontal Lobe

The front portion of the cerebral cortex involved in planning, judgment, decision-making, personality, impulse control, voluntary movement, and speech production.

Motor Cortex

A region at the back of the frontal lobe that controls voluntary movements by sending signals to skeletal muscles.

Broca's Area

A brain region, usually located in the left frontal lobe, involved in producing speech; damage causes difficulty speaking fluently.

Parietal Lobe

A region of the cerebral cortex that processes bodily sensations such as touch, temperature, pressure, and pain, and aids in spatial awareness.

Somatosensory Cortex

A region in the parietal lobe that receives and processes sensory information from the body, including touch, pressure, temperature, and aspects of pain.

Occipital Lobe

The lobe located at the back of the brain dedicated to processing visual information.

Temporal Lobe

A region of the cerebral cortex involved in hearing, language comprehension, memory, and recognition.

Wernicke's Area

A brain region, usually in the left temporal region, important for understanding spoken and written language; damage may cause fluent but meaningless speech.

Right Hemisphere

The right half of the brain, which controls movement and sensations from the left side of the body and specializes in spatial processing, facial recognition, and nonverbal communication.

Left Hemisphere

The left half of the brain, which controls movement and sensations from the right side of the body and specializes in language and analytical processing.

Corpus Callosum

A thick bundle of nerve fibers connecting the left and right cerebral hemispheres that enables communication between them.

Peripheral Nervous System (PNS)

All the nerves located outside the brain and spinal cord that connect the central nervous system to the rest of the body.

Somatic Nervous System

The division of the peripheral nervous system responsible for voluntary control of skeletal muscles and carrying sensory information to the central nervous system.

Autonomic Nervous System

The division of the peripheral nervous system that regulates involuntary bodily functions such as heart rate, digestion, and gland activity.

Sympathetic Nervous System

The division of the autonomic nervous system that activates fight-or-flight responses by increasing heart rate, dilating pupils, and slowing digestion during stress.

Parasympathetic Nervous System

The division of the autonomic nervous system that calms the body and conserves energy by slowing heart rate and promoting digestion.

Pituitary Gland

A small endocrine gland beneath the hypothalamus known as the "master gland" that releases hormones regulating growth and controlling other endocrine glands.

Adrenaline (Epinephrine)

A hormone released by the adrenal glands during stress or excitement that increases heart rate, breathing, and energy availability for fight-or-flight responses.