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Fig. 1. Schematic diagram of the behavioral testing apparatus used to elicit and
analyze goldfish C-starts. Light is projected from above and fish
images are captured from below the tank by both a video camera and a matrix
camera. Goldfish are stimulated with a vibratory stimulus created by lifting
the whole tank with a solenoid. The computer simultaneously triggers the
solenoid and the matrix camera, which starts saving silhouettes at a rate of
500 silhouettes s-1 (i.e. every 2 ms). These fish silhouettes are
stored in the expanded memory of a controller and then loaded onto the
computer hard drive for analysis.