AP Psychology Unit 1: Biological Processes, Sensation, Heredity, and Sleep

Flashcards on biological bases of behavior, neural firing, nervous system divisions, sensory systems, environmental and genetic influences, and sleep science.

Neurons

Specialized cells that transmit electrical and chemical signals throughout the brain and body.

Glial Cells

Support cells in the nervous system that provide structure, insulation, and waste removal for neurons.

Neuron Structure

The anatomical components of a nerve cell, including the nucleus, soma/cell body, dendrites, axon hillock, axon, myelin sheath, nodes of Ranvier, and axon terminals.

Reflex Arc

A simple, automatic response pathway in the spinal cord consisting of sensory neurons that detect a stimulus, interneurons that process information, and motor neurons that activate a response.

All-or-Nothing Principle

The principle that a neuron either fires completely or does not fire at all once its stimulation threshold is reached.

Depolarization

An electrical shift across a neuron's membrane that initiates a neural signal.

Refractory Period

A brief pause following neural firing during which the neuron cannot fire again.

Resting Potential

The stable, resting state of readiness of a neuron before it receives a signal to fire.

Reuptake

The process by which neurotransmitters are reabsorbed by the sending neuron after firing across the synapse.

Threshold

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

Dopamine

A neurotransmitter involved in movement, learning, and pleasure, linked to Parkinson's disease and schizophrenia.

Serotonin

A neurotransmitter that regulates mood and appetite, low levels of which are associated with depression.

Norepinephrine

A neurotransmitter that plays a key role in alertness and arousal.

Glutamate

The primary excitatory neurotransmitter in the brain, essential for learning.

GABA

The primary inhibitory neurotransmitter in the brain that reduces anxiety and neural excitation.

Endorphins

Natural painkilling neurotransmitters released during physical exertion or stress.

Substance P

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

Acetylcholine

A neurotransmitter responsible for enabling muscle movement and memory formation.

Adrenaline

A hormone that increases heart rate and energy during stressful or dangerous situations.

Leptin

A hormone responsible for regulating hunger signals and metabolism.

Ghrelin

A hormone released to trigger hunger signals in the body.

Melatonin

A hormone secreted to regulate sleep-wake cycles, low levels of which contribute to insomnia.

Oxytocin

A hormone that promotes bonding, trust, and social connection.

Agonists

Drugs or substances that mimic or enhance the action of specific neurotransmitters.

Antagonists

Drugs or substances that block receptor sites, preventing neurotransmitters from binding.

Reuptake Inhibitors

Drugs that block the reabsorption of neurotransmitters, leaving more active neurotransmitters in the synaptic gap.

Stimulants

A class of psychoactive drugs, such as caffeine and cocaine, that increase neural activity and bodily functions.

Depressants

A class of psychoactive drugs, such as alcohol, that reduce neural activity and slow bodily functions.

Hallucinogens

A class of psychoactive drugs, such as marijuana, that distort perceptions and alter sensory experiences.

Opioids

A class of drugs, such as heroin and morphine, that relieve pain and induce euphoria by binding to endorphin receptors.

Tolerance

The requirement of larger doses of a drug over time to achieve the initial effect due to brain adaptation.

Addiction

A chronic condition marked by compulsive drug seeking and use despite negative consequences.

Withdrawal

The physical or psychological discomfort experienced when an individual discontinues an addictive substance.

Central Nervous System (CNS)

The primary control center of the body comprising the brain and spinal cord.

Peripheral Nervous System (PNS)

The network of nerves connecting the central nervous system to muscles, organs, and sensory glands throughout the body.

Autonomic Nervous System

The subsystem of the PNS that regulates involuntary functions such as heart rate, digestion, and breathing.

Sympathetic Nervous System

The branch of the autonomic nervous system that prepares the body for action by triggering the fight-or-flight response.

Parasympathetic Nervous System

The branch of the autonomic nervous system that calms the body and restores internal balance following arousal.

Somatic Nervous System

The subsystem of the PNS that governs voluntary muscle movements.

Sensation

The process of detecting environmental stimuli that meet a threshold and transducing them into neurochemical messages for perception.

Just-Noticeable Difference

The minimal difference in intensity between two stimuli required for a person to detect the difference 50% of the time.

Weber's Law

Ernst Weber's principle stating that the size of a just-noticeable difference is a constant proportion of the initial stimulus intensity.

Sensory Interaction

The principle that different sensory systems continuously collaborate to influence overall perception.

Sensory Adaptation

The reduction in sensory receptor sensitivity caused by continuous exposure to an unchanging stimulus.

Synesthesia

A sensory phenomenon where stimulation in one modality produces an involuntary experience in another sense.

Cones

Retinal receptor cells concentrated near the fovea that function best in daylight and detect fine detail and color.

Rods

Retinal receptor cells located in the periphery that function well in low light and detect movement, black, white, and gray.

Parts of the Eye

The visual structures including the cornea, pupil, iris, lens, retina, macula, optic nerve, sclera, choroid, ciliary body, and vitreous body.

Trichromatic Theory

The theory proposing that color vision results from combinations of red, green, and blue cone receptor signals.

Opponent Process Theory

The theory asserting that visual receptors process opposing colors (red-green, yellow-blue, black-white) along shared neural pathways.

Prosopagnosia

A neurological condition marked by face blindness resulting from an inability of the occipital lobes to recognize faces.

Sound Localization

The brain's capability to locate a sound source by calculating slight differences in timing and intensity between both ears.

Anatomy of the Ear

The structural features of the ear, including the auricle (pinna), ear canal, tympanum (eardrum), malleus (hammer), incus (anvil), stapes (stirrup), semicircular canals, cochlea, eustachian tube, and auditory nerve.

Place Theory

An auditory theory stating that pitch perception depends on the specific location where hair cells are activated on the basilar membrane.

Frequency Theory

An auditory theory proposing that pitch perception corresponds to the speed at which nerve impulses travel along the auditory nerve.

Volley Theory

The theory that groups of auditory neurons fire in alternating sequences to transmit high-frequency sound pitch.

Conductive Hearing Loss

Hearing loss resulting from physical damage to mechanical components of the outer or middle ear.

Sensorineural Hearing Loss

Hearing loss caused by dysfunction or damage to inner ear hair cells or the auditory nerve.

Olfaction

The sense of smell, initiated by odorant receptors in the nasal cavity, which is the only sensory pathway that bypasses the thalamus.

Pheromones

Chemical signals emitted by an individual that trigger physiological or behavioral responses in members of the same species.

Gustation

The chemical sense of taste, comprising six primary qualities: salty, sweet, bitter, sour, umami, and oleogustus.

Taste Bud Anatomy

The microscopic structure of gustatory sense organs, including the taste pore, taste receptor cells, basal cells, epithelium, and afferent nerve fibers.

Gate-Control Theory

The pain model proposing that small nerve fibers transmit pain signals, while larger nerve fibers can close a neural gate to block pain.

Kinesthesia

The sense that detects the position, orientation, and movement of individual body parts.

Vestibular Sense

The sense responsible for maintaining body balance and head orientation through fluid movement inside the semicircular canals and vestibular sacs.

Heredity

The genetic transmission of physical and behavioral characteristics from biological parents to their offspring.

Environmental Factors

All non-genetic external influences, such as family upbringing, culture, education, and chemical exposures, that affect behavior and gene expression.

Natural Selection

Charles Darwin's evolutionary mechanism wherein inherited variations that enhance survival and reproduction are continuously passed down.

Circadian Rhythm

The body's natural 24-hour cycle regulating physical, mental, and behavioral changes in response to light and darkness.

REM Sleep

A stage of sleep marked by rapid eye movement, high brain activity, vivid dreaming, and temporary motor muscle paralysis induced by the brain stem.

NREM-3

The deep sleep stage dominated by delta brain waves, during which tissue repair, immune recovery, and chemical waste clearance occur in the brain.

Activation-Synthesis Theory

Hobson and McCarley's theory proposing that dreams are generated when the brain attempts to synthesize random electrical signals from REM sleep into a coherent narrative.

Consolidation Theory

The perspective holding that sleep, especially REM sleep, facilitates the stabilization and transfer of short-term memories into long-term storage.

Insomnia

A persistent sleep disorder involving ongoing difficulties falling asleep or staying asleep.

Narcolepsy

A neurological disorder marked by uncontrollable, sudden episodes of falling asleep during waking hours.

Sleep Apnea

A sleep disorder characterized by repeated temporary cessation of breathing that interrupts deep sleep cycles.

REM Sleep Behavior Disorder

A parasomnia in which normal muscular paralysis during REM sleep fails, causing individuals to physically act out their dreams.

Somnambulism

A non-REM sleep disorder commonly known as sleepwalking, wherein individuals engage in complex physical activities while remaining asleep.