Sensation Vocabulary Flashcards

Vocabulary practice flashcards covering terms related to sensation, vision, audition, gustation, olfaction, and somatosensory systems from the lecture slide.

Sensation

The process by which sensory receptors and the nervous system receive and represent stimulus energies from the environment.

Transduction

The conversion of one form of energy into another, such as transforming stimulus energies into neural impulses the brain can interpret.

Absolute threshold

The minimum stimulus energy needed to detect a particular stimulus 50 percent of the time.

Just-noticeable difference

The minimum difference between two stimuli required for detection 50 percent of the time.

Sensory adaptation

Diminished sensitivity to a stimulus as a consequence of constant, unchanging stimulation.

Weber's law

The principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage rather than a constant amount.

Sensory interaction

The principle that one sense may influence another, such as when the smell of food influences its taste.

Synesthesia

A neurological condition in which stimulation of one sensory or cognitive pathway leads to involuntary experiences in a second sensory or cognitive pathway.

Retina

The light-sensitive inner surface of the eye containing photoreceptor cells plus layers of neurons that begin processing visual information.

Blind spot

The point at which the optic nerve leaves the eye, creating a region where no photoreceptor cells are located.

Visual nerve

The nerve pathway that carries neural impulses from the eye to the brain.

Lens

The transparent structure behind the pupil that changes shape to help focus images on the retina.

Accommodation

The process by which the eye's lens changes shape to focus near or far objects on the retina.

Nearsightedness

A visual condition in which nearby objects are seen clearly while distant objects appear blurry because images focus in front of the retina.

Farsightedness

A visual condition in which distant objects are seen clearly while near objects appear blurry because images focus behind the retina.

Photoreceptors

Specialized sensory receptor cells in the retina that convert light energy into neural signals.

Rods

Retinal photoreceptors that detect black, white, and gray, and are necessary for peripheral and night vision.

Cones (blue, green, red)

Retinal photoreceptors concentrated near the center of the retina that function in bright light, detecting fine detail and color in blue, green, and red wavelengths.

Trichromatic theory

The theory that the retina contains three different types of color receptors (sensitive to red, green, and blue) which together can produce the perception of any color.

Opponent-process theory

The theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision.

Afterimages

Visual sensations that persist after the stimulus that caused them has ceased, often appearing in complementary colors due to fatigue in opponent-process cells.

Ganglion cells

Neurons in the retina whose axons converge to form the optic nerve and transmit visual signals to the brain.

Dichromatism

A form of color deficiency caused by the lack of one type of cone photoreceptor, resulting in difficulty distinguishing certain colors.

Monochromatism

Complete color blindness caused by the absence or dysfunction of two or three types of cones, resulting in vision restricted to shades of gray.

Prosopagnosia

A neurological condition characterized by the inability to recognize familiar faces despite intact general visual perception.

Blindsight

A condition in which a person responds to a visual stimulus without consciously experiencing seeing it.

Wavelength

The distance from the peak of one light or sound wave to the peak of the next, determining hue in vision and pitch in hearing.

Pitch

A tone's experienced highness or lowness, which depends directly on the frequency of the sound wave.

Amplitude

The height of a wave, which determines brightness in light waves and loudness in sound waves.

Loudness

The perception of auditory intensity, determined primarily by the amplitude of sound waves.

Pitch perception

The sensory and cognitive processing mechanism by which the auditory system interprets the pitch or frequency of a sound.

Place theory

The pitch perception theory asserting that we hear different pitches because sound waves trigger activity at different places along the cochlea's basilar membrane.

Volley theory

The pitch perception theory stating that neural impulses fire in rapid succession (volleys) to achieve a combined frequency capable of encoding medium-to-high pitch sounds.

Frequency theory

The pitch perception theory stating that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone.

Sound localization

The process by which the auditory system determines the location or source of a sound in space using arrival time and intensity differences between ears.

Conduction deafness

Hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea.

Sensorineural deafness

Hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves.

Olfactory system

The sensory system responsible for the sense of smell.

Thalamus

The brain's sensory control center that routes sensory messages to appropriate areas in the cortex (with the exception of smell).

Pheromones

Chemical substances secreted by an organism that trigger a specific behavioral or physiological response in other members of the same species.

Gustation

The sensory system and process responsible for taste perception.

Sweet, sour, salty, bitter, umami, oleogustus

The recognized basic taste qualities detected by taste receptors in the mouth.

Taste receptors

Sensory receptor cells located in taste buds that detect chemical substances dissolved in saliva.

Supertasters

Individuals with an unusually high density of taste papillae who experience taste sensations with heightened intensity.

Medium tasters

Individuals with an average density of taste papillae who perceive tastes at a typical intensity level.

Nontasters

Individuals with a lower density of taste papillae who experience taste sensations with reduced intensity.

Warm/cold receptors

Thermoreceptors located in the skin that are specialized to detect increases (warmth) or decreases (cold) in temperature.

Gate control theory

The theory that the spinal cord contains a neurological gate that blocks pain signals or allows them to pass on to the brain.

Phantom limb

The experience of sensory sensations or pain felt in a limb or body part that has been amputated.

Vestibular sense

The sense of body movement and position, including the sense of balance.

Semicircular canals

Three fluid-filled structures in the inner ear that monitor head movement and rotational motion to maintain balance.

Kinesthesis

The system for sensing the position and movement of individual body parts through receptors in muscles, tendons, and joints.