Lesson 12C: Ear and Audition

Audition

The process of transducing sound waves into neural signals.

Auricle

The large external structure of the ear also known as the pinna.

Tympanic Membrane

Also known as the eardrum; it vibrates when struck by sound waves.

Ossicles

Three tiny bones in the middle ear: malleus, incus, and stapes.

Eustachian Tube

A tube that connects the middle ear to the pharynx; helps equilibrate air pressure.

Cochlea

A spiral-shaped structure in the inner ear responsible for hearing.

Scala Vestibuli

The upper fluid-filled tube within the cochlea that begins at the oval window.

Scala Tympani

The lower fluid-filled tube within the cochlea that ends at the round window.

Organs of Corti

Sensory structures within the cochlear duct that transduce wave motion into neural signals.

Stereocilia

Hair-like projections from hair cells that play a critical role in hearing.

Round Window

A membrane-covered opening that allows fluid movement in the cochlea.

Basilar Membrane

A membrane in the cochlea that vibrates in response to fluid waves, aiding in sound perception.

Neural Signal Transduction

The processes by which auditory information is transformed into electrical signals for the brain.

Vestibulocochlear Nerve (CN VIII)

The nerve responsible for transmitting auditory and balance information from the inner ear to the brain.

K+ Ion Channels

Mechanically-gated channels in hair cells that open to allow K+ influx during depolarization.

Hair Cells

Mechanoreceptors in the cochlea that detect sound vibrations and convert them into neural signals.

Pathway of Hearing

The sequence of events from sound wave entry to signal processing in the temporal lobe.