Scala tympani is one of the perilymph

Perilymph

Perilymph is an extracellular fluid located within the cochlea in two of its three compartments: the scala tympani and scala vestibuli. The ionic composition of perilymph is comparable to that of plasma and cerebrospinal fluid...

-filled cavities in the cochlear labyrinth of the human ear. It is separated from the scala media

Scala media

The cochlear duct is an endolymph filled cavity inside the cochlea, located in between the scala tympani and the scala vestibuli, separated by the basilar membrane and Reissner's membrane respectively....

 by the basilar membrane

Basilar membrane

The basilar membrane within the cochlea of the inner ear is a stiff structural element that separates two liquid-filled tubes that run along the coil of the cochlea, the scala media and the scala tympani .-Function:...

, and it extends from the round window

Round window

The round window is one of the two openings into the inner ear. It is closed off from the middle ear by the round window membrane, which vibrates with opposite phase to vibrations entering the inner ear through the oval window...

 to the helicotrema

Helicotrema

The helicotrema is the part of the cochlear labyrinth where the scala tympani and the scala vestibuli meet. It is the main component of the cochlear apex. The hair cells in this area best detect low frequency sounds.-External links:* at Allegheny University of the Health Sciences* at IUPUI...

, where it continues as scala vestibuli

Scala vestibuli

Scala vestibuli is a perilymph-filled cavity inside the cochlea of the inner ear that conducts sound vibrations to the scala media.It is separated from the scala media by Reissner's membrane and extends from the vestibule of the ear to the helicotrema where it joins scala tympani.-External links:* ...

.

The purpose of the perilymph-filled scala tympani and scala vestibuli

Scala vestibuli

Scala vestibuli is a perilymph-filled cavity inside the cochlea of the inner ear that conducts sound vibrations to the scala media.It is separated from the scala media by Reissner's membrane and extends from the vestibule of the ear to the helicotrema where it joins scala tympani.-External links:* ...

 is to transduce the movement of air that causes the tympanic membrane and the ossicles

Ossicles

The ossicles are the three smallest bones in the human body. They are contained within the middle ear space and serve to transmit sounds from the air to the fluid-filled labyrinth . The absence of the auditory ossicles would constitute a moderate-to-severe hearing loss...

 to vibrate, to movement of liquid and the basilar membrane

Basilar membrane

The basilar membrane within the cochlea of the inner ear is a stiff structural element that separates two liquid-filled tubes that run along the coil of the cochlea, the scala media and the scala tympani .-Function:...

. This movement is conveyed to the organ of Corti

Organ of Corti

The organ of Corti is the organ in the inner ear of mammals that contains auditory sensory cells, or "hair cells."The organ was named after the Italian anatomist Marquis Alfonso Giacomo Gaspare Corti , who conducted microscopic research of the mammaliean auditory system.-Structure and function:The...

 inside the scala media, composed of hair cell

Hair cell

Hair cells are the sensory receptors of both the auditory system and the vestibular system in all vertebrates. In mammals, the auditory hair cells are located within the organ of Corti on a thin basilar membrane in the cochlea of the inner ear...

s attached to the basilar membrane and their stereocilia

Stereocilia

In the inner ear, stereocilia are the mechanosensing organelles of hair cells, which respond to fluid motion in numerous types of animals for various functions, including hearing and balance. They are about 10–50 micrometers in length and share some similar features of microvilli...

 embedded in the tectorial membrane

Tectorial membrane

Tectorial membrane can refer to:*Tectorial membrane *Tectorial membrane...

. The movement of the basilar membrane compared to the tectorial membrane causes the sterocilia to bend. They then depolarise

Depolarization

In biology, depolarization is a change in a cell's membrane potential, making it more positive, or less negative. In neurons and some other cells, a large enough depolarization may result in an action potential...

 and send impulses to the brain via the cochlear nerve

Cochlear nerve

The cochlear nerve is a nerve in the head that carries signals from the cochlea of the inner ear to the brain...

. This produces the sensation of sound

Sound

Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.-Propagation of...

.

External links

• Slide from University of Kansas
  University of Kansas
  The University of Kansas is a public research university and the largest university in the state of Kansas. KU campuses are located in Lawrence, Wichita, Overland Park, and Kansas City, Kansas with the main campus being located in Lawrence on Mount Oread, the highest point in Lawrence. The...
  
  
• Diagram at IUPUI
• Image at University of New England, Maine
  University of New England, Maine
  The University of New England is an independent, coeducational university with two campuses in Maine: the main campus in Biddeford and another in Portland.- History :...