Sound localization in ¢shes requires that otolith organs
respond directly to the acoustic particle motion
(vector) component of underwater sound, similar to
accelerometers. Hair cells are directional receivers
(Hudspeth and Corey, 1977) covering the otolithic organ
epithelia in patterns such that their axes of best
sensitivity are oriented di¡erently (e.g., Popper and
Platt, 1993). The axis of particle motion is hypothesized
to be determined from the array of primary a¡erents
that receive