Stereocilia showing tip links

Colour-enhanced, close-up image of stereocilia on the outer hair cells of the cochlea. When the stereocilia are deflected by sound, the fine tip links that connect them are stretched. This causes ion channels to open allowing potassium and calcium ions to flow into the cell. This in turn sets off nerve signals that carry the sound information to the brain. If the tip links fail to function properly, sound signals will not be transferred to the brain and deafness will result. Conversely, if the ion channels remain open, signals will be constantly flowing to the brain. This may help to explain tinnitus.