Distance Determination via the Lateral Line in the Mottled Sculpin

We determined the ability of blinded mottled sculpin (Cottus bairdi) to determine the distance from the trunk of a vertically oscillating sphere. Sphere distance from the trunk and oscillation amplitude was varied randomly. Fish were trained to respond to a one-cycle oscillation (50 Hz) by attempting to touch the sphere with the mouth in one movement from the fish's initial position. Each of the four fish was tested with both left and right trunk canals intact. Afterward, one canal was blocked with a nylon thread and the other left intact. Precision of distance determination was measured as the correlation coefficient of the distance from the sphere to the fish's trunk before stimulus onset and the response distance. Fish were significantly better at distance determination with intact canals than on the side with the canal blocked (P < 0.001).