Carlson and Baker
In fish that can detect variation in signal waveform, the receptors, shown as pink dots, are distributed across the body surface (top left). These receptors spontaneously generate spikes at low rates (middle left). When responses to 10 repetitions of an electric stimulus pulse are superimposed on one another (bottom left), it is clear that each stimulus repetition elicits a short-latency spike. In fish that cannot detection variation in signal waveform, the receptors are organized into three clusters, or rosettes, on the head (top right). These receptors generate spontaneous oscillations (middle right). An electric stimulus pulse resets the oscillation phase: across 10 stimulus repetitions, the oscillations are out of phase with one another before the stimulus, but reset to the same phase just after the stimulus (bottom right).