- audition
- sense of hearing
- auricle
- cartilaginous outer ear
- basilar membrane
- stiff structure in the cochlea that indirectly anchors auditory receptors
- bipolar neuron
- neuron with two processes extending from the cell body, typically in opposite directions
- candela
- (cd) unit of measurement of luminous intensity (brightness)
- circadian
- describes a time cycle about one day in length
- cochlea
- whorled structure that contains receptors for transduction of the mechanical wave into an electrical signal
- cone
- weakly photosensitive, chromatic, cone-shaped neuron in the fovea of the retina that detects bright light and is used in daytime color vision
- cornea
- transparent layer over the front of the eye that helps focus light waves
- fovea
- region in the center of the retina with a high density of photoreceptors and which is responsible for acute vision
- free nerve ending
- ending of an afferent neuron that lacks a specialized structure for detection of sensory stimuli; some respond to touch, pain, or temperature
- glabrous
- describes the non-hairy skin found on palms and fingers, soles of feet, and lips of humans and other primates
- glomerulus
- in the olfactory bulb, one of the two neural clusters that receives signals from one type of olfactory receptor
- Golgi tendon organ
- muscular proprioceptive tension receptor that provides the sensory component of the Golgi tendon reflex
- gustation
- sense of taste
- hyperopia
- (also, farsightedness) visual defect in which the image focus falls behind the retina, thereby making images in the distance clear, but close-up images blurry
- incus
- (also, anvil) second of the three bones of the middle ear
- inner ear
- innermost part of the ear; consists of the cochlea and the vestibular system
- iris
- pigmented, circular muscle at the front of the eye that regulates the amount of light entering the eye
- kinesthesia
- sense of body movement
- labyrinth
- bony, hollow structure that is the most internal part of the ear; contains the sites of transduction of auditory and vestibular information
- lens
- transparent, convex structure behind the cornea that helps focus light waves on the retina
- malleus
- (also, hammer) first of the three bones of the middle ear
- mechanoreceptor
- sensory receptor modified to respond to mechanical disturbance such as being bent, touch, pressure, motion, and sound
- Meissner’s corpuscle
- (also, tactile corpuscle) encapsulated, rapidly-adapting mechanoreceptor in the skin that responds to light touch
- Merkel's disc
- unencapsulated, slowly-adapting mechanoreceptor in the skin that responds to touch
- middle ear
- part of the hearing apparatus that functions to transfer energy from the tympanum to the oval window of the inner ear
- muscle spindle
- proprioceptive stretch receptor that lies within a muscle and that shortens the muscle to an optimal length for efficient contraction
- myopia
- (also, nearsightedness) visual defect in which the image focus falls in front of the retina, thereby making images in the distance blurry, but close-up images clear
- nociception
- neural processing of noxious (such as damaging) stimuli
- odorant
- airborne molecule that stimulates an olfactory receptor
- olfaction
- sense of smell
- olfactory bulb
- neural structure in the vertebrate brain that receives signals from olfactory receptors
- olfactory epithelium
- specialized tissue in the nasal cavity where olfactory receptors are located
- olfactory receptor
- dendrite of a specialized neuron
- organ of Corti
- in the basilar membrane, the site of the transduction of sound, a mechanical wave, to a neural signal
- ossicle
- one of the three bones of the middle ear
- outer ear
- part of the ear that consists of the auricle, ear canal, and tympanum and which conducts sound waves into the middle ear
- oval window
- thin diaphragm between the middle and inner ears that receives sound waves from contact with the stapes bone of the middle ear
- Pacinian corpuscle
- encapsulated mechanoreceptor in the skin that responds to deep pressure and vibration
- papilla
- one of the small bump-like projections from the tongue
- perception
- individual interpretation of a sensation; a brain function
- pheromone
- substance released by an animal that can affect the physiology or behavior of other animals
- presbyopia
- visual defect in which the image focus falls behind the retina, thereby making images in the distance clear, but close-up images blurry; caused by age-based changes in the lens
- proprioception
- sense of limb position; used to track kinesthesia
- pupil
- small opening through which light enters
- reception
- receipt of a signal (such as light or sound) by sensory receptors
- receptive field
- region in space in which a stimulus can activate a given sensory receptor
- receptor potential
- membrane potential in a sensory receptor in response to detection of a stimulus
- retina
- layer of photoreceptive and supporting cells on the inner surface of the back of the eye
- rhodopsin
- main photopigment in vertebrates
- rod
- strongly photosensitive, achromatic, cylindrical neuron in the outer edges of the retina that detects dim light and is used in peripheral and nighttime vision
- Ruffini ending
- (also, bulbous corpuscle) slowly-adapting mechanoreceptor in the skin that responds to skin stretch and joint position
- semicircular canal
- one of three half-circular, fluid-filled tubes in the vestibular labyrinth that monitors angular acceleration and deceleration
- sensory receptor
- specialized neuron or other cells associated with a neuron that is modified to receive specific sensory input
- sensory transduction
- conversion of a sensory stimulus into electrical energy in the nervous system by a change in the membrane potential
- stapes
- (also, stirrup) third of the three bones of the middle ear
- stereocilia
- in the auditory system, hair-like projections from hair cells that help detect sound waves
- superior colliculus
- paired structure in the top of the midbrain, which manages eye movements and auditory integration
- suprachiasmatic nucleus
- cluster of cells in the hypothalamus that plays a role in the circadian cycle
- tastant
- food molecule that stimulates gustatory receptors
- taste bud
- clusters of taste cells
- tectorial membrane
- cochlear structure that lies above the hair cells and participates in the transduction of sound at the hair cells
- tonic activity
- in a neuron, slight continuous activity while at rest
- tympanum
- (also, tympanic membrane or ear drum) thin diaphragm between the outer and middle ears
- ultrasound
- sound frequencies above the human detectable ceiling of approximately 20,000 Hz
- umami
- one of the five basic tastes, which is described as “savory” and which may be largely the taste of L-glutamate
- vestibular sense
- sense of spatial orientation and balance
- vision
- sense of sight