Figure 7.

Dynamics of disparity tuning with stimulus-triggered spikes. A, Spike density functions triggered on the presence of positive correlation in the images at a particular disparity. These correlations at the preferred disparity (disparity 1) produce a transient increase in activity. At disparities 2 and 3, they produce a transient reduction in activity. Disparity 2 produced the weakest response during the rising phase of the response, whereas disparity 3 produced the weakest response during the decay. The minimum response for disparity 2 precedes the minimum for disparity 3. B, From spike density functions for all disparities, two cross-sections were extracted showing disparity selectivity at different times. A delay of 10 ms before the optimal represented the rising phase. The decaying phase was 10 ms after the optimal. The disparities shown in A are marked with the corresponding numbers. In this example, the disparity tuning sharpened over time. C, Population data. The disparity-tuning functions were transformed to frequency spectra (after zero padding to improve the frequency resolution). The peak frequencies were expressed as multiples of the fundamental frequency (units of octave). The peaks of the spectra shifted to higher frequencies over time.