Fig. 8. Responses of a type I medial octavolateralis nucleus (MON) unit to a 50 Hz vibrating sphere stimulus in still (left) and running (15.5 cm s^-1; right) water. Raster plots and level-response functions are as in Fig. 4. Displacement amplitudes were 2720, 1660 and 560 µm. In still water, this unit responded to the vibrating sphere with an increase in discharge rate. Ongoing discharge rates in still and running water were comparable. Nevertheless, the response to the vibrating sphere was masked both in terms of spike rate and phase-coupling.