(Top) A tip link, consisting of Protocadherin 15 (blue) and Cadherin 23 (gold) connects the MET complex at the top of one stereocilium to the actin core of the stereocilium in the next tallest row. Overstimulation, such as from loud noise, can cause tip link breakage (bottom left). According to [23], a temporary tip link, consisting of only Protocadherin 15, is formed within about 12 hours of damage, partially reestablishing MET channel function (bottom middle). Within about 36 hours after damage, the Protocadherin 15 at the top half of the tip link is replaced by Cadherin 23 to allow full restoration of MET function (bottom right).