Fig. 12. Responses of three type I medial octavolateralis nucleus (MON) units to a
50 Hz vibrating sphere stimulus. Raster plots are shown of the responses to
the sphere presented at two distinct locations along the side of the fish
(indicated by open and filled circles). Displacement amplitude was 2717 µm.
(A) Example of a unit that responded with a decrease in discharge rate when
the sphere was in the head region and with an increase in discharge rate when
the sphere was in the trunk region. Both responses were masked in running
water. (B) Example of a unit that responded with an increase in discharge rate
when the sphere was near the caudal peduncle and when the sphere was in the
trunk region. Neither of these responses was masked in running water. (C)
Example of a unit that responded with an increase in discharge rate when the
sphere was opposite to the operculum and with a decrease in discharge rate
when the sphere was near the tip of the snout. The response elicited by the
sphere placed near the operculum was not masked, whereas that elicited by the
sphere placed near the snout was masked by running water.
