20-21 Module

Module 20: 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 (e.g., per second).
Pitch – A tone's experienced highness or lowness; depends on frequency.

Middle Ear – The chamber between the eardrum and cochlea, containing three tiny bones (hammer, anvil, and stirrup) that concentrate vibrations on the cochlea's oval window.
Cochlea [KOHK-lee-uh] – A coiled, bony, fluid-filled tube in the inner ear; sound waves travel through the cochlear fluid and trigger nerve impulses.
Inner Ear – The innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs.

Sensorineural Hearing Loss – Caused by damage to the cochlea’s receptor cells or auditory nerves; the most common form of hearing loss (also called nerve deafness).
Conduction Hearing Loss – A less common form of hearing loss, caused by damage to the mechanical system that conducts sound waves to the cochlea.

Cochlear Implant – A device that converts sounds into electrical signals and stimulates the auditory nerve through electrodes threaded into the cochlea.
Place Theory – The theory that links the pitch we hear with the place where the cochlea’s membrane is stimulated.
Frequency Theory – The theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, enabling us to sense its pitch (also called temporal theory).

Gate-Control Theory – The theory that the spinal cord contains a neurological "gate" that blocks pain signals or allows them to pass to the brain. The gate is opened by the activity of pain signals traveling up small nerve fibers.
Kinesthesia [kin-ehs-THEE-zhuh] – Our movement sense; the system for sensing the position and movement of individual body parts.
Vestibular Sense – Our sense of body movement and position, enabling balance.

Olfaction – The sense of smell.
Sensory Interaction – The principle that one sense may influence another, such as when the smell of food influences its taste.
Embodied Cognition – The influence of bodily sensations, gestures, and other states on cognitive preferences and judgments.