Figure 4.

(A) Model mean MSTd population activation using a steeper sigmoidal signal function compared to Figure 3A (see Table 1). The model produces linear peak timing in near (green), behaviorally relevant (red), and far (cyan) conditions while qualitatively simulating the low frequency deflections present in the Dubin and Duffy (2009) data (Figure 1). The behaviorally irrelevant condition (blue) does not yield a distinct peak, thereby qualitatively matching the data of Dubin and Duffy (2009). (B) Model mean population MSTd population activation of cells selective to the FoE position (windowed). The solid and dashed gray curves show the activation of units not selective to the FoE in the near and far conditions, respectively. (C) Model mean MSTd population activation in a network that features distance-dependent competition and windowing, which better reflect neurophysiological and experimental conditions. Consistent with the data of Dubin and Duffy (2009) (Figure 1), the curves for all conditions drop off more steeply after peaking, the peak in the behaviorally relevant case has higher contrast, and the behaviorally irrelevant condition response is flatter.