Unit 6 C: Audition

audition

the sense of hearing

frequency

the number of complete waves that pass a given point in a certain amount of time; in audition it determines pitch

amplitude

the height of a wave; in audition it determines loudness or intensity of a sound

pitch

the highness or lowness of a sound; it is determined by the frequency of sound waves

outer ear

visible part of the ear (called the pinna or auricle) and the auditory canal

auditory canal

part of the outer ear that channels sounds from the outside to the eardrum

middle ear

the chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea's oval window

eardrum

the membrane that seperates the outer ear from the middle ear and that vibrates when sound waves strike it; also called the tympanic membrane

ossicles

The three smallest bones in the human body which amplfy sound vibrations in the middle ear. They are the malleus (hammer), incus (anvil), and stapes (stirrup).

inner ear

the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs

cochlea

a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses

oval window

membrane that covers the opening between the middle ear and inner ear

basilar membrane

A structure that runs the length of the cochlea in the inner ear and holds the auditory receptors, called hair cells.

hair cells

receptor cells for hearing found in the cochlea

place theory

in hearing, the theory that links the pitch we hear with the place where the cochlea's membrane is stimulated; best for explaining high-pitched sounds

frequency theory

in hearing, the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch; best for explaining low-pitched sounds

volley principle

neural cells alternate firing so that they achieve a combined frequency that goes much higher than what they could do on their own; explains high-pitched noises for frequency theory (ex. soldiers who alternative firing so the others can reload)

sound localization

the process by which you determine the location of a sound; based on differences in timing and intensity of experience between two ears

conduction hearing loss

hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea (i.e., damage to the eardrum or ossicles)

sensorineural hearing loss

hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerves; also called nerve deafness

nerve deafness

hearing loss caused by damage to the cochlea's receptor cells or to the auditory nerve; also called sensorineural hearing loss

auditory nerve

the nerve that carries impulses from the inner ear to the brain, resulting in the perception of sound

cochlear implant

a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea