Vibrations of the guinea pig organ of Corti in the apical turn.

Vibrations of the organ of Corti were measured in response to sound applied to the ear in the apical turn of a living guinea pig. Measurements were made at 29 points on the Reissner's membrane (RM) at 10 micro spacing along a radial track. Measurements also included 22 points on the reticular lamina (RL), Claudius' cells and osseous spiral lamina. Our goal was to characterize the vibration of the RM and the RL with high spatial resolution along a radial axis. The tuning and spatial patterns of the RM are compared in the radial direction with those for the RL at the fundamental frequency and at the second harmonic. The shape of the RM tuning curve changes with radial position, and differ significantly from those observed at the RL. These results support our earlier findings (Hao and Khanna, Hear. Res. 99 (1996) 176-189).