Audition and the Ear

Audition

Audition

the sense/ act of hearing via sound waves

Loudness

determined by amplitude of a wave (more amplitude equals more of this)

Amplitude

height of a wave measured in dB

Pitch

the tone of a sound; dependent on frequency (higher frequency = higher of this)

Frequency

the number of wavelengths that pass a point in a period of time

Pinna

the outer ear lobe which collects sound

External auditory canal (ear canal)

channels sound waves to the eardrum, where earwax is

outer ear

pinna and canal

middle ear

eardrum and bones

Eardrum

thin membrane that vibrates when sound waves hit it

Ossicles

feel vibrations from eardrum and send sound to inner ear

Hammer

1st ossicle

Anvil

2nd Ossicle

Stirrup

3rd Ossicle

Inner Ear

where transduction occurs

Cochlea

snail; filled with fluid where sound waves pass and trigger neural impulses

Basilar Membrane

inner lining of cochlea with hair cells that help stimulate neurons and transduce

Auditory Nerve

sends sound neural impulses to brain (opposite thalamus to temporal lobe)

Place Theory

pitch theory; we hear pitch based on which place in the cochlea is stimulated by the vibrations (different sounds reach different spots in the cochlea) - explains high pitched sounds better!

Frequency Theory

pitch theory; the rate of nerve impulses matches the frequency of the tone (high rate equals high pitch) - Explains low pitched sounds better!

Conductive deafness

loss of hearing because sound waves are blocked from transferring from the outer to the inner ear (ex. tumor, object, infection) - treatable and typically temporary

Sensorineural deafness

loss of hearing because of damage to inner ear or auditory nerve (can be from birth or lasting impact of illness)

Cochlear Implant

hearing aid which helps restore hearing after neural issues IF auditory nerve is healthy (converts sound to electrical signals)

Kennard Principle

it is better to be injured when younger because of the brains greater neuroplasticity (brain developing/ can bounce back easier)