ap psych unit 1

Define: Genetic predisposition

An increased likelihood of developing a trait, behavior, or disorder because of inherited genetic factors; it increases probability but does not guarantee an outcome.

Define: Neuron

A nerve cell that receives, processes, and transmits information through electrical and chemical signals.

Define: Multiple sclerosis (MS)

A disease in which the immune system damages myelin, disrupting neural communication and often causing problems with movement, sensation, or coordination.

Define: Neural transmission

The process by which neurons communicate using electrical signals within a neuron and chemical neurotransmitters between neurons.

Define: Resting potential

The neuron's stable negative electrical charge when it is not firing, typically about -70 millivolts.

Define: Threshold

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

Define: Action potential

A brief electrical impulse that travels down an axon when a neuron fires.

Define: All-or-none principle

A neuron either fires a complete action potential once threshold is reached or does not fire at all; stronger stimulation does not create a larger action potential.

Define: Depolarization

The process during an action potential in which the inside of a neuron becomes less negative and briefly more positive.

Define: Excitatory neurotransmitter

A neurotransmitter that increases the likelihood that the receiving neuron will reach threshold and fire.

Define: Inhibitory neurotransmitter

A neurotransmitter that decreases the likelihood that the receiving neuron will reach threshold and fire.

Define: Dopamine

A neurotransmitter involved in movement, reward, motivation, attention, and emotion; abnormal dopamine activity is associated with disorders such as Parkinson's disease and schizophrenia.

Define: Serotonin

A neurotransmitter involved in mood, sleep, appetite, and arousal.

Define: Norepinephrine

A neurotransmitter involved in alertness, arousal, and the fight-or-flight response.

Define: Glutamate

The brain's major excitatory neurotransmitter; important for learning and memory.

Define: GABA

The brain's major inhibitory neurotransmitter; it helps reduce neural activity.

Define: Endorphins

Natural neurotransmitters that reduce pain and can produce feelings of pleasure or well-being.

Define: Substance P

A neurotransmitter involved primarily in transmitting pain signals.

Define: Acetylcholine (ACh)

A neurotransmitter involved in muscle movement, learning, and memory; deterioration of ACh-producing neurons is associated with Alzheimer's disease.

Define: Alzheimer's disease

A progressive neurodegenerative disorder involving severe memory loss and cognitive decline; associated with deterioration of acetylcholine-producing neurons.

Define: Myasthenia gravis

An autoimmune disorder in which antibodies interfere with acetylcholine receptors, causing muscle weakness.

Define: Sensory neurons (afferent neurons)

Neurons that carry incoming information from sensory receptors to the central nervous system.

Define: Interneurons

Neurons within the central nervous system that communicate between sensory and motor neurons and process information.

Define: Motor neurons (efferent neurons)

Neurons that carry outgoing instructions from the central nervous system to muscles and glands.

Define: Central nervous system (CNS)

The brain and spinal cord; it processes and integrates information and coordinates responses.

Define: Peripheral nervous system (PNS)

All nerves outside the brain and spinal cord; it connects the CNS to the rest of the body.

Define: Reflex arc

A rapid, automatic neural pathway in which sensory information can be processed through the spinal cord before the brain becomes consciously involved.

Define: Somatic nervous system

The division of the PNS that controls voluntary skeletal muscles and carries sensory information to the CNS.

Define: Autonomic nervous system

The division of the PNS that automatically regulates glands and internal organs.

Define: Sympathetic nervous system

The autonomic division that arouses the body for action, producing the fight-or-flight response.

Define: Parasympathetic nervous system

The autonomic division that calms the body and conserves energy, producing the rest-and-digest response.

Define: Endocrine system

A system of glands that secretes hormones into the bloodstream to regulate growth, metabolism, reproduction, and other bodily processes.

Define: Hormones

Chemical messengers released by endocrine glands and carried through the bloodstream to target tissues.

Define: Adrenaline (epinephrine)

A hormone that increases physiological arousal, such as heart rate and energy availability, during stress or excitement.

Define: Leptin

A hormone associated with long-term energy balance that signals satiety and helps regulate appetite.

Define: Ghrelin

A hormone, largely produced by the stomach, that increases hunger and appetite.

Define: Melatonin

A hormone that helps regulate circadian rhythms and sleep-wake cycles.

Define: Oxytocin

A hormone and neurotransmitter involved in childbirth, lactation, social bonding, and trust-related behaviors.

Define: Lesioning

A research method involving the destruction, removal, or damage of brain tissue to study the function of a brain area.

Define: Electroencephalogram (EEG)

A technique that records the brain's electrical activity using electrodes placed on the scalp; useful for measuring brain-wave activity and sleep patterns.

Define: Functional magnetic resonance imaging (fMRI)

A brain-imaging technique that detects changes in blood oxygenation and flow, helping identify which brain areas are active during specific tasks.

Define: Medulla

A brainstem structure that controls vital automatic functions such as breathing and heart rate.

Define: Cerebellum

A structure at the rear of the brain that coordinates balance, posture, fine motor movement, and motor learning.

Define: Reticular formation

A network in the brainstem involved in arousal, alertness, and the sleep-wake cycle.

Define: Thalamus

A sensory relay station that directs most incoming sensory information, except smell, to appropriate areas of the cerebral cortex.

Define: Hypothalamus

A small structure that regulates homeostasis, including hunger, thirst, body temperature, and the endocrine system; it helps control the pituitary gland.

Define: Amygdala

A limbic system structure involved in processing emotion, especially fear, aggression, and emotionally significant experiences.

Define: Hippocampus

A limbic system structure essential for forming and consolidating new explicit memories.

Define: Brainstem

The lower part of the brain connecting the spinal cord with higher brain regions; it regulates many basic survival functions, including breathing and arousal.

Define: Cerebral cortex

The thin outer layer of the cerebrum responsible for complex thinking, perception, voluntary movement, and language.

Define: Limbic system

A group of interconnected brain structures involved in emotion, motivation, and memory.

Define: Contralateral hemispheric organization

The tendency for each cerebral hemisphere to control and receive information primarily from the opposite side of the body.

Define: Hemispheric specialization

The tendency for the left and right cerebral hemispheres to perform somewhat different functions.

Define: Split-brain patients

People whose corpus callosum has been surgically severed or damaged, limiting communication between the two cerebral hemispheres.

Define: Corpus callosum

A large band of nerve fibers that connects the left and right cerebral hemispheres and allows them to communicate.

Define: Lobes of the cerebral cortex

Major divisions of the cerebral cortex: frontal, parietal, occipital, and temporal lobes, each associated with specialized functions.

Define: Association areas

Areas of the cerebral cortex involved in higher mental functions such as learning, memory, thinking, judgment, and language.

Define: Frontal lobes

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

Define: Prefrontal cortex

The frontmost part of the frontal lobes involved in executive functions such as planning, impulse control, working memory, and decision-making.

Define: Central executive

The component of working memory that directs attention and coordinates information from other working-memory systems.

Define: Broca's area

Usually located in the left frontal lobe; involved in producing speech and language.

Define: Aphasia

An impairment of language ability caused by brain damage, affecting speech production, comprehension, or both.

Define: Wernicke's area

Usually located in the left temporal lobe; involved in understanding spoken and written language.

Define: Motor cortex

A strip of cortex at the rear of the frontal lobes that controls voluntary movements.

Define: Parietal lobes

Cortical regions near the top and rear of the brain involved in processing touch and body-position information and integrating sensory input.

Define: Somatosensory cortex

A strip of cortex at the front of the parietal lobes that receives and processes sensations such as touch, pressure, temperature, and pain.

Define: Phantom limb syndrome

The experience of sensations, including pain, in a limb that has been amputated, reflecting the brain's continuing representation of that body part.

Define: Occipital lobes

Cortical regions at the back of the brain primarily responsible for processing visual information.

Define: Temporal lobes

Cortical regions on the sides of the brain involved in auditory processing, language, and aspects of memory.

Define: Linguistic processing

The brain's processing of language, including understanding and producing spoken, written, or signed communication.