Human Sensation, Consciousness, and Attention

Comprehensive vocabulary flashcards covering pain mechanisms, body senses, chemical senses, consciousness, attention processes, and attention disorders based on the lecture transcript.

Nociceptors

Specialized sensory cells embedded in the skin designed to detect and signal pain.

Mechanoreceptors

Specialized receptors embedded in the skin responsible for detecting the sense of touch.

Thermoreceptors

Specialized receptors embedded in the skin responsible for detecting changes in temperature.

Gate Control Theory of Pain

The theory proposing that neural impulses generated by pain receptors can be blocked or gated at the level of the spinal cord before reaching the brain for perception.

Large Fibers

Nerve fibers whose activation shuts the spinal gate, preventing pain signals from reaching the brain for perception (activated by physical stimuli like ice or psychological comfort).

Small Fibers

Nerve fibers whose activation inhibits the closing of the gate, opening it up and allowing pain to be perceived by the brain.

Endorphins

The body's natural morphine-like chemicals that act on the opioid system to suppress pain signals and produce pain-killing effects.

Kinesthesis

The body sense that provides information about where limbs are in space through specialized receptors located in muscles that detect elongation and contraction.

Vestibular Sense

The body sense originating within the inner ear that contributes to balance, movement, and perceiving gravity.

Semicircular Canals

Three fluid-filled canals attached to the cochlea oriented in different directions whose moving fluid contributes to balance and perception of gravity.

Chemoreceptors

The broad class of receptors for both taste and smell that bind chemical molecules from food, liquid, or air and convert them into action potentials.

Olfaction

The chemical sense of smell, initiated when airborne chemical odorants bind to receptors in the nasal cavity.

Cilia (Olfactory)

Small hair-like extensions hanging down from chemoreceptors at the top of the nasal cavity that bind airborne odorant chemicals.

Olfactory Bulb

A brain structure serving as a processing pit stop that receives sensory inputs from olfactory receptor cells before sending signals to regions like the thalamus and primary olfactory cortex.

Gustation

The official scientific term for the sense of taste.

Bitter

A taste quality consisting of poison alkaloids, generally avoided across the animal kingdom because it signals that food may cause illness or death.

Sour

A taste quality that generally signals a food is unripe or spoiled, typically leading to avoidance.

Sweet

A taste quality that serves as a safety signal indicating foods full of sugars necessary for maintaining energy stores.

Salty

A taste quality signaling the presence of sodium chloride, which is necessary for cellular balance and neural action potentials.

Umami

A savory taste quality indicating the presence of monosodium glutamate in food, commonly detected in red meats and mushrooms.

Flavor

A full perceptual experience combining bottom-up sensory input (taste and smell) with top-down cognitive factors (visual appearance, expectations, and price).

Papillae

Visible bumps on the tongue that contain grooves and crevices where taste buds reside.

Taste Buds

Flower-bud-like sensory structures located in the grooves around papillae (estimated at roughly 10,000 in the mouth), each composed of 20 to 50 individual taste receptor cells.

Taste Receptor Cells

Individual chemoreceptors within taste buds specialized for detecting specific tastes, possessing a high turnover rate of about 10 days.

Capsaicin

A chemical found in spicy foods that binds directly to nociceptors rather than taste receptors, producing sensations of heat and pain.

Synesthesia

A neurological condition characterized by sensory crossover, where stimulation of one sense automatically triggers the experience of another sense.

Misophonia

A neurological condition in which specific sounds (such as chewing, clicking pens, or rustling paper) trigger intense emotional, behavioral, and physiological distress.

Consciousness

An individual's awareness of and ability to respond to their surroundings, as well as awareness of their own internal mental processes.

Preconscious

A level of consciousness consisting of thoughts and memories not currently in active awareness but accessible and easily called to mind.

Unconscious

A level of consciousness consisting of thoughts and experiences that a person is not aware of and cannot consciously access.

Sentience

The subjective ability to know oneself, characterized by self-awareness and understanding that one is a distinct individual separate from others.

Attention

Internal cognitive processes used to set a priority list for allocating mental resources and controlling behavior.

Selective Attention

The process of focusing conscious awareness on specific environmental inputs while filtering out competing stimuli.

Inattentional Blindness

A failure to detect unexpected objects that are fully visible in the visual field because focused attention is directed elsewhere.

Dichotic Listening Technique

An experimental procedure used to study attention (introduced in the 1950s by Daniel Brogden) where participants hear two different auditory messages simultaneously through headphones in separate ears.

Cocktail Party Effect

The ability to focus on a single auditory conversation in a noisy environment while still unconsciously monitoring background stimuli for personally meaningful information, such as one's name.

Automaticity

Fast and effortless cognitive or behavioral processing that requires little to no focused conscious attention once a skill is mastered.

Visual Neglect

An attentional disorder, typically caused by a stroke damaging the parietal lobe, characterized by a tendency to completely ignore stimuli on one side of the perceptual world (usually the left side).