Hearing Science

What is the main function of the pinna?

It collects sound and directs it to the ear canal

What part of the ear amplifies frequencies between 2.5-3.5 kHz?

The external ear canal

Why is amplification of 2.5-3.5 kHz important?

Speech sounds fall within this frequency range

What kind of cavity is the middle ear?

An air-filled cavity

What structure separates the outer ear from the middle ear?

The tympanic membrane (eardrum)

What are the three ossicles in order from outermost to innermost?

Malleus, incus, stapes

Which ossicle connects to the inner ear?

The stapes

What is the function of the Eustachian tube?

To ventilate the middle ear and drain fluid

Why are middle ear infections more common in infants?

Infants’ eustachian tubes are less steep than adults

What mechanism in the middle ear amplifies sound?

The area difference between the tympanic membrane and the stapes footplate

What is a useful analogy for sound amplification by the middle ear?

A thumb tack

What fills the inner ear?

Both perilymph and endolymph

What is the main hearing structure in the inner ear

The cochlea

Which structure lies above the hair cells inside the cochlea?

The tectorial membrane

What are the sensory receptors for hearing called?

Hair cells

What are the two types of hair cells

Inner hair cells and outer hair cells

What membrane supports the hair cells in the cochlea?

The basilar membrane