ear

In the inner ear (cochlea) the sound is converted into neural activity. Basilar membrane acts as a divider of two fluids (scala media and the scala tympani) and the hair cells pick up movement in order to send a signal to the brain to interpret the sound. ii. The organ of corti is an extremely sensitive area of the cochlea. It transforms pressure waves into action potentials iii.

--the tectorial membrane in which the hair cells are embedded). This movement bends the hair cells to cause receptor potentials in these cells which in turn cause the release of transmitter onto the neurons of the auditory nerve. In this case, the hair cell receptors are very pressure sensitive. The greater the force of the vibrations on the membrane, the more the hair cells bend and hence the greater the receptor potential generated by these hair cells.

On the other side of the eardrum is the fluid-filled cochlea. The eustashian tube helps with equalizing pressure on both sides of the eardrum, which allows the eardrum to freely move back and forth. As a sound wave enters the canal, it pushes the eardrum in and out, which causes the eardrum to vibrate like a trampoline when you jump on it. When this happens, the vibrations set the ossicles into motion. The ossicles are made up of three little bones, the malleus, incus and stapes.

These sound waves cause the eardrum to vibrate. The vibrations are caught by the middle ear, a set of small bones, which transfer the vibrations to the cochlea (inner ear). Here, the sound waves are converted to neural impulses. The neural network in the human brain decodes information from both ears. Within the cochlea resides a basilar membrane, a supporting structure for the cochlea nerve.

The waves then travel to the inner ear or cochlea which is the site of sound's transduction into chemical energy. Within the cochlea, sound waves travel through fluid which stimulates the stereocilia, small hair-like projections of hair cells along the basilar membrane. The actions of the stereocilia cause the release of K+, potentially depolarizing the cell (1). The flexibility of the basilar membrane allows stereocilia to move back and forth in response to the waves in the Cochlear fluid. Each stereocilium is linked to another through structures called "tip links" (1) , (3) As the stereocilia move towards the tallest ones, the tip links cause ion channels to open, depolarizing the cell and allowing free K+ to move into the cell (1).

Vibrating air moving at different frequencies hits the eardrum which causes the middle ear's three bones to move accordingly. The stapes, one of these inner ear bones hits on the oval window of the inner ear, and because the inner ear is filled with fluid, the bulging of the oval window causes this fluid to slosh around. The round window, also in the inner ear, compensates for the increased pressure by bulging outward. The inner ear has two functions, to transduce sound via the cochlea and to maintain a person's vertical position with respect to gravity via the vestibular system (1). .

The eardrum is a thin membrane stretched in the inner end of the canal. Air pressure which caused by the sound waves, cause the eardrum to vibrate. Then, these vibrations are transmitted to three small bones called (Ossicles) which located in the middle ear. Middle ear perceive vibrations and conduct them to another thin membrane called the (Oval window) which separates the middle ear from the inner ear. The inner ear contains the (Cochlea), a spiral-shaped structure that contains the organ of (Corti) which sits in a sensitive membrane called the (basilar membrane).

Otitis media with Effusion (OME) The Ear The ear is made up of an outer (external), middle and inner ear. The outer and middle ear is mainly involved in transmitting sounds to the inner ear where that sound is processed. The first step in this process involves sound waves entering the external auditory canal and passing the tympanic membrane (otherwise known as the eardrum- this separates the outer ear from the middle ear)( Vander A, Sherman J, Luciano D, 2001). As small air molecules (sound) passes through the tympanic membrane they cause it to vibrate and these vibrations are then passed onto the middle ear (Moore KL, Agur MRA, 2002). The middle ear formed from 3 tiny bones (malleus, incus and stapes)- known as auditory ossicles then amplify this sound onto the oval window (which separates the middle and inner ear).

The ear is able to pick up sound waves and transfer them into nerve impulses that can be read by the brain. Background: A sound wave is pressure variations in air. Sound waves move through air the same as a wave in water. A sound wave is caused by an objects vibrations that cause the air surrounding it to vibrate. When the air vibrates it, the ear drum picks up the vibrations and translates them to the brain.

The ear is made up of three areas: the outer, middle, and inner ear. The outer ear is very important for collecting sound waves. It is made up of the pinna and the ear canal. The pinna, the actual physical outward appearance of the ear, receives sound waves and begins to funnel them into the ear canal. The ear canal is also known as the auditory meatus which is basically a convoluted tube.