Figure 1.

A–D, Speed tuning curves computed from the responses of four different MT neurons (three single units, one multiunit). Each neuron is represented by a pair of tuning curves showing its mean control and cooling responses (±SEM). Some cells responded best to slow speeds (A, preferred speed 1.6°/s), others to faster speeds (B, 50.2°/s), and others to medium speeds (C, D, 12.8°/s, 17.5 °/s). The median control speed across the population was 15.2°/s. Curves show the log Gaussian fits, points and vertical lines show the mean and SEM, and black and gray colors represent precooling and cooling responses. Black arrows indicate equivalent responses before cooling (see Speed tuning in main text).