9 - Hearing, Vestibular Perception, Taste, and Smell Flashcards
External ear
The part of the ear that we readily see (the pinna) and the canal that leads to the eardrum
Transduction
The conversion of one form of energy to another
Pinna
The external part of the ear
Pure tone
A tone with a single frequency of vibration
Amplitude
The force sound exerts per unit area, usually measured as dynes per square centimeter
Loudness
The subjective experience of the pressure level of a sound
Frequency
The number of cycles per second in a sound wave, measured in hertz (Hz)
Hertz (Hz)
Cycles per second, as of an auditory stimulus
Pitch
A dimension of auditory experience in which sounds vary from low to high
Fundamental
The predominant frequency of an auditory tone or a visual scene
Harmonics
Multiples of a particular frequency called the fundamental
Timbre
The characteristic sound quality of a musical instrument, as determined by the relative intensities of its various harmonics
Fourier analysis
The analysis of a complex pattern into the sum of sine waves
Decibel (dB)
A measure of sound intensity
Middle ear
The cavity between the tympanic membrane and the cochlea
Ossicles
Three small bones (incus, malleus, and stapes) that transmit sound across the middle ear, from the tympanic membrane to the oval window
Tympanic membrane
Also called eardrum. The partition between the external ear and the middle ear
Oval window
The opening from the middle ear to the inner ear
Malleus
Latin for “hammer.” A middle-ear bone that is connected to the tympanic membrane
Incus
Latin for “anvil.” A middle-ear bone situated between the malleus and the stapes
Stapes
Latin for “stirrup.” A middle-ear bone that is connected to the oval window
Tensor tympani
The muscle attached to the malleus that modulates mechanical linkage to protect the delicate receptor cells of the inner ear from damaging sounds
Stapedius
A middle-ear muscle that is attached to the stapes
Inner ear
The cochlea and vestibular apparatus
Cochlea
A snail-shaped structure in the inner ear that contains the primary receptor cells for hearing
Scala vestibuli
Also called vestibular canal. One of three principle canals running along the length of the cochlea
Scala media
Also called middle canal. The central of the three spiraling canals inside the cochlea, situated between the scala vestibuli and the scala tympani
Scala tympani
Also called tympanic canal. One of three principle canals running along the length of the cochlea
Round window
A membrane separating the cochlear duct from the middle-ear cavity
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
Hair cell
One of the receptor cells for hearing in the cochlea
Basilar membrane
A membrane in the cochlea that contains the principle structures involved in auditory transduction
Inner hair cell (IHC)
One of the two types of receptor cells for hearing in the cochlea
Outer hair cell (OHC)
One of the two types of receptor cells for hearing in the cochlea
Stereocilium
A relatively stiff hair that protrudes from a hair cell in the auditory or vestibular system
Tectorial membrane
A membrane that sits atop the organ of Corti in the cochlear duct
Tip link
A fine, threadlike fiber that runs along and connects the tips of stereocilia
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
Otoacoustic emission
A sound produced by the cochlea itself, either spontaneously or in response to an environmental noise
Tuning curve
A graph of responses of a single auditory nerve fiber or neuron to sounds that vary in frequency and intensity
Vestibulocochlear nerve
Cranial nerve VIII, which runs from the cochlea to the brainstem auditory nuclei
Cochlear nuclei
Brainstem nuclei that receive input from auditory hair cells and send output to the superior olivary complex