AP Psychology: Unit 4 Topic 4

Hearing and the Ear

audition

the sense or act of hearing

frequency

the number of complete wavelengths that pass a point in a given time

decibels

a unit used to measure the intensity or loudness of a sound

pitch

a tone’s experienced highness or lowness; depends on the frequency

middle ear

the chamber between the eardrum and cochlea containing three tiny bones that concentrate the vibrations of the eardrum on the cochlea’s oval window

cochlea

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

inner ear

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

basilar membrane

a thin, flexible strip of tissue inside the inner ear's cochlea that vibrates in response to different sound frequencies

place theory

we hear different pitches because different sound waves trigger activity at different spots along the cochlea’s basilar membrane (hard to determine location on the basilar membrane where low pitch stimulates)

frequency theory

the brain reads pitch by monitoring the frequency of neural impulses traveling up the auditory nerve

sound localization

the perceptual process of determining the location of a sound's origin

conduction hearing loss

hearing loss caused by damage to the mechanical system that conducts sounds waves to the cochlea

sensorineural hearing loss

hearing loss caused by damage to the cochlea’s hair cell receptors or to the auditory nerve; also called nerve deafness

cochlear implant

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