CHAPTER 9

Description:	HEARING, VESTIBULAR, TASTE & SMELL
Category:	Physiology
Created by:	lisadaychild on 2009-11-05

Question	Answer
AMPLITUDE	The distance of particle movement in a defined period of time, usually measured as dynes per square centimeter.
AMPULLA	An enlarged region of each semicircular canal that contains the receptor cells (hair cells) of the vestibular system.
AMUSIA	A disorder characterized by the inability to discern tunes accurately.
ANOSMIA	The inability to smell.
AUDITORY BRAIN IMPLANT ABI	A type of auditory prosthesis in which implanted microphones directly stimulate the auditory nuclei of the brainstem rather than the cochlea.
BASILAR MEMBRANE	A membrane in the cochlea that contains the principal structures involved in auditory transduction.
BINAURAL	Pertaining to two ears.
CENTRAL DEAFNESS	A hearing impairment that is related to lesions in auditory pathways or centers, including sites in the brainstem, thalamus, or cortex.
CILIUM	A hairlike extension
CIRCUMVALLATE	One of three types of small structures on the tongue, located in the back, that contain taste receptors.
CHOCLEA	A snail-shaped structure in the inner ear that contains the primary receptor cells for hearing.
COCHLEAR AMPLIFIER	The mechanism by which the cochlea is physically distorted by outer hair cells in order to “tune” the cochlea to be particularly sensitive to some frequencies more than others.
COCHLEAR IMPLANT	An electromechanical device that detects sounds and selectively stimulates nerves in different regions of the cochlea via surgically implanted electrodes.
COCHLEAR NUCLEI	Brainstem nuclei that receive input from auditory hair cells and send output to the superior olivary complex.
COINCIDENCE DETECTOR	A device that senses the co-occurence of two events.
CONDUCTIN DEAFNESS	A hearing impairment that is associated with pathology of the external-ear or middle-ear cavities.
CORTICAL DEAFNESS	A hearing impairment that is caused by a fault or defect in the cortex.
CUPULA	A small gelatinous column that forms part of the lateral-line system of aquatic animals and also occurs within the vestibular system of mammals.
DECIBEL dB	A measure of sound intensity.
DENDRITIC KNOB	A portion of olfactory receptor cells present in the olfactory epithelium.
DUPLEX THEORY	A theory of pitch perception that combines place theory and volley theory.
EXTERNAL EAR	The part of the ear that we readily see (the pinna) and the canal that leads to the eardrum.
FOLIATE PAPILLAE	One of three types of small structures on the tongue, located along the sides, that contain taste receptors.
FOURIER ANALYSIS	The analysis of a complex pattern into the sum of sine waves.
FREQUENCY	The number of cycles per second in a sound wave; measured in hertz (Hz).
FUNDAMENTAL	The predominant frequency of an auditory tone or a visual scene.
FUNGIFORM PAPILLAE	One of three types of small structures on the tongue, located in the front, that contain taste receptors.
GLOMERULUS	A complex arbor of dendrites from a group of olfactory cells.
GUSTATORY SYSTEM	The taste system.
HAIR CELL	One of the receptor cells for hearing in the cochlea.
HARMONICS	Multiples of a particular frequency called the fundamental.
HERTZ Hz	Cycles per second, as of an auditory stimulus.
INCUS	Latin for anvil. A middle-ear bone situated between the malleus and the stapes.
INFERIOR COLLICULI	Paired structures on the dorsal surface of the midbrain, caudal to the superior colliculi, that receive auditory information.
INFRASOUND	Very low frequency sound; in general, below the threshold for human hearing, at about 20 Hz.
INNER EAR	The cochlea and vestibular apparatus.
INNER HAIR CELL (IHC)	One of the two types of receptor cells for hearing in the cochlea.
INTENSITY DIFFERENCES	Perceived differences in loudness between the two ears, which can be used to localize a sound source.
LABLED LINES	The concept that each nerve input to the brain reports only a particular type of information.
LATENCY DIFFERENCES	Differences between the two ears in the time of arrival of a sound, which can be employed by the nervous system to localize sound sources.
LATERAL-LINE SYSTEM	A sensory system, found in many kinds of fishes and some amphibians, that informs the animal of water motion in relation to the body surface.
LOUDNESS	The subjective experience of the pressure level of a sound.
MALLEUS	Latin for hammer. A middle-ear bone that is connected to the tympanic membrane.
MEDIAL GENICULATE NUCLEI	Nuclei in the thalamus that receive input from the inferior colliculus and send output to the auditory cortex.
MIDDLE EAR	The cavity between the tympanic membrane and the cochlea.
MINIMAL DISCRIMINABLE FREQUENCY DIFFERENCE	The smallest change in frequency that can be detected reliably between two tones.
MITRAL CELL	A type of cell in the olfactory bulb that conducts smell information from the glomeruli to the rest of the brain.
MITRAL CELL	A type of cell in the olfactory bulb that conducts smell information from the glomeruli to the rest of the brain.
MONAURAL	Pertaining to one ear.
MOTION SICKNESS	The experience of nausea brought on by unnatural passive movement, as in a car or boat.
OLFACTORY BULB	An anterior projection of the brain that terminates in the upper nasal passages and, through small openings in the skull, provides receptors for smell.
OLFACTORY EPITHELIUM	A sheet of cells, including olfactory receptors, that lines the dorsal portion of the nasal cavities and adjacent regions, including the septum that separates the left and right nasal cavities.
ORGAN OF CORTI	A structure in the inner ear that lies on the basilar membrane of the cochlea and contains the hair cells and terminations of the auditory nerve.
OSSICLES	Three small bones (incus, malleus, and stapes) that transmit sound across the middle ear, from the tympanic membrane to the oval window.
OTOACOUSTIC EMISSION	A sound produced by the cochlea itself, either spontaneously or in response to an environmental noise.
otolith	A small bony crystal on the gelatinous membrane in the vestibular system.
ototoxic	Toxic to the ears, especially the middle or inner ear.
outer hair cell (OHC)	One of the two types of receptor cells for hearing in the cochlea.
oval window	The opening from the middle ear to the inner ear.
papilla	A small bump that projects from the surface of the tongue. Papillae contain most of the taste receptor cells.
pattern coding	Coding of information in sensory systems based on the temporal pattern of action potentials.
pheromone	A chemical signal that is released outside the body of an animal and affects other members of the same species.
pinna	The external part of the ear.
pitch	A dimension of auditory experience in which sounds vary from low to high.
place theory	A theory of frequency discrimination stating that pitch perception depends on the place of maximal displacement of the basilar membrane produced by a sound.
polymodal or multisensory	Involving several sensory modalities.
pure tone	A tone with a single frequency of vibration.
round window	A membrane separating the cochlear duct from the middle-ear cavity.
saccule	A small, fluid-filled sac under the utricle in the vestibular system that responds to static positions of the head.