Fig. 4.

Model fits of the response tuning curves elicited by bidirectional stimuli of 2 example neurons. A and C: 2 motion components both moved at 100% coherence. B and D: the clockwise-side component moved at 100% coherence, and the CC-side component moved at 60% coherence. A and B: example neuron 1. All 3 models, linear weighted summation (LWS), simplified normalization (DivNorm), and summation plus nonlinear interaction (SNL), provided good fits. The fitting results of these models were almost identical, and therefore curves of different model fits are overlapping. C and D: example neuron 2. The LWS and DivNorm model fits are nearly identical in D. Error bars of the bidirectional responses indicate standard errors.