Ear (IMAGE) Max-Planck-Gesellschaft Caption When sound waves reach the snail-shaped structure of the inner ear, sensory cells are activated. If the hair-like cilia of such cells are damaged by a mutation of the SMPX gene, they can no longer respond to acoustic stimuli. Credit fotolia Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.