psycology ch 2 flash card

CT Scan (Computed Tomography)

An imaging technique that uses X-ray beams and computer processing to create cross-sectional images of bone and tissue; often used to diagnose acute injuries like fractures or bleeding.

MRI (Magnetic Resonance Imaging)

A brain-imaging technique that uses powerful magnetic fields and radio waves to produce detailed structural images of soft tissue.

PET Scan (Positron Emission Tomography)

A neuroimaging method that injects radioactive glucose tracers to display active chemical and metabolic processes in the brain.

EEG (Electroencephalography)

A technique using electrodes placed on the scalp to record rhythmic waves of electrical activity generated by neurons; commonly used to evaluate sleep disorders and seizures.

Medulla

The base of the brainstem that regulates vital autonomic life-support functions, such as breathing, heart rate, and blood pressure.

Pons

A brainstem structure that regulates sleep-wake cycles, coordinates body movements, and relays communication between the cerebellum and the rest of the brain.

Reticular Formation

A nerve network within the brainstem that filters incoming sensory stimuli and plays a key role in controlling arousal and alertness.

Thalamus

The brain's central sensory relay station that routes incoming signals from all senses (except smell) to higher cortical areas.

Hippocampus

A limbic system structure critical for processing, consolidating, and forming new long-term memories.

Amygdala

Two almond-shaped neural clusters in the limbic system that regulate core emotional responses, especially fear, aggression, and threat processing.

Corpus Callosum

The thick band of neural axon fibers connecting the left and right cerebral hemispheres, enabling interhemispheric communication.

Frontal Lobe

The cerebral lobe responsible for higher-order cognitive functions such as planning, reasoning, impulse control, abstract thinking, and voluntary movement.

Parietal Lobe

The cerebral lobe that processes somatosensory input, including touch, temperature, pressure, pain, and spatial orientation.

Temporal Lobe

The cerebral lobe responsible for auditory processing, language comprehension, and long-term memory integration.

Occipital Lobe

The cerebral lobe located at the rear of the skull dedicated to receiving and processing visual stimuli.

Motor Cortex

The region at the posterior edge of the frontal lobe that plans, controls, and executes voluntary muscle movements.

Somatosensory Cortex

The strip of tissue situated at the front of the parietal lobe that registers and processes bodily sensations like touch, pressure, and temperature.

Broca's Area

A region in the left frontal lobe that governs motor speech production and grammatical sentence construction.

Wernicke's Area

A region in the left temporal lobe crucial for comprehending spoken and written language and formulating meaningful speech.

Central Nervous System (CNS)

The master division of the nervous system consisting of the brain and spinal cord.

Peripheral Nervous System (PNS)

The sensory and motor neurons that link the central nervous system to the limbs, organs, and rest of the body.

Sympathetic Nervous System

The autonomic branch that mobilizes body systems during stress, triggering the 'fight-or-flight' response by elevating heart rate, breathing, and alertness.

Parasympathetic Nervous System

The autonomic branch that conserves energy and calms the body, initiating 'rest-and-digest' operations to reduce heart rate and stimulate digestion.

Action Potential

A brief electrochemical impulse that travels down an axon to convey neural signals.

Myelin Sheath

A protective layer of fatty tissue wrapping around neural axons that speeds up electrical signal transmission.

Dendrites

Branching extensions of a neuron that receive chemical messages from neighboring cells and direct impulses toward the soma.

Axon Terminals

Branches at the ending tip of an axon that package neurotransmitters into vesicles to release signals across synaptic clefts.

Synapse

The microscopic junction or gap where chemical communication occurs between sending and receiving neurons.

Refractory Period

The brief resting pause after an action potential fires during which a neuron cannot fire another impulse until baseline polarization resets.

Afferent (Sensory) Neurons

Nerve cells that transmit incoming sensory data from sensory receptors inward to the spinal cord and brain.

Efferent (Motor) Neurons

Nerve cells that relay outgoing motor instructions from the brain and spinal cord out to muscles and glands.

Neuroplasticity

The brain's capacity to modify its neural wiring, establish new connections, and compensate for damage or changing environmental demands.

Serotonin

A key neurotransmitter that modulates mood, sleep patterns, emotional stability, and appetite.

Acetylcholine (ACh)

A neurotransmitter essential for voluntary muscle contraction, memory, and cognitive learning; deterioration of producing neurons is linked to Alzheimer's disease.

Endorphins

Internally synthesized, opiate-like neurotransmitters that relieve pain sensation and elevate mood.

Epinephrine

A neurotransmitter and hormone (also known as adrenaline) that elevates heart rate and energy supply during acute physical stress.

Transduction

The conversion of external sensory stimuli (like light or sound waves) into neural impulses the brain can process.

Absolute Threshold

The minimum level of stimulus energy required to be consciously detected at least $50\%$ of the time.

Sensory Adaptation

A reduction in sensitivity that occurs when sensory receptors are exposed to constant, unchanging stimulation.

Bottom-Up Processing

Information processing that starts at raw sensory receptors and works up to higher-level integration in the brain without prior expectations.

Top-Down Processing

Perceptual processing guided by cognitive factors, context, memories, and personal expectations.

Gate-Control Theory

The theory that non-painful input closes spinal gates to painful input, preventing pain sensations from traveling to the central nervous system.

Perceptual Set

A mental predisposition or mental expectation that biases how sensory data is interpreted.

Opponent-Process Theory

The theory that color perception relies on three opposing paired retinal channels: red-green, blue-yellow, and black-white.

Rods

Retinal photoreceptor cells that detect black, white, and gray; essential for peripheral and twilight/dim-light vision.

Cones

Retinal photoreceptors clustered in the fovea that function under bright light conditions to perceive fine detail and color.

Fovea

The central focal point of the retina containing a high concentration of cones where visual visual acuity is highest.

Blind Spot

The area on the retina devoid of photoreceptors where the optic nerve exits the posterior of the eye.

Cochlea

A coiled, bony, fluid-filled inner-ear chamber lined with hair cells where mechanical sound waves are transduced into neural signals.

Semicircular Canals

Three fluid-filled bony loops in the inner ear that monitor dynamic head movement and rotational balance.

Vestibular Sense

The sensory system providing feedback regarding whole-body balance, orientation, and movement in gravitational space.

Sensorineural Hearing Loss

Hearing impairment caused by physical damage to the cochlea's hair cell receptors or the auditory nerve.

Conduction Hearing Loss

Hearing impairment caused by mechanical problems in conducting sound waves through the eardrum or the ossicles of the middle ear.

Place Theory

The hearing theory stating that pitch perception correlates with the specific anatomical location stimulated along the cochlea's basilar membrane.

Frequency Theory

The hearing theory asserting that the rate of nerve impulses traveling up the auditory nerve matches the exact frequency of a sound wave.

Olfaction and Gustation

The chemical sensory systems for smell and taste, the latter comprising five basic categories: sweet, sour, salty, bitter, and umami.