Supplementary Figure 8: Additional examples of two-dimensional tuning.

The neuron (a) fires preferentially at a tilt angle of 20° nose-down and has a very broad tuning curve. In neuron (b), the highest firing rate was recorded at the highest tilt angle used in the study. It is plausible, and likely, that this neuron’s firing rate would increase when tilt exceeds 45°. Thus we cannot determine the location of the neuron’s peak response, but we can conclude that it equals or exceeds 45°. Neuron (c) is one of 3 cells that showed bimodal tuning. Neuron (d) is dG-tuned and fires preferentially at a tilt angle of 11°. Neuron (e) is dG-tuned and fires preferentially at a tilt angle equal or in excess of 45°. In d and e, ND (nose-down), LED (left ear down), NU (nose-up) and RED (right ear down) refer to the direction of tilt velocity. These measurements were obtained in n=31 cells