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Fig. 5.28. Long-range lateral connections in the combined OR/OD map. The inhibitory lateral connections for four sample neurons from the regions marked in Figure 5.27 are shown situated on the OR preference and selectivity map (top) and the OD map (bottom) as in Figures 5.12 and 5.17. The connection patterns on the OR map are similar to those in the orientation-only map. The most selective iso-OR neurons (a) are located near the OD stripe boundaries, and receive connections equally from neurons of both eye preferences. Neurons in iso-OR regions away from the OD boundaries connect more strongly to one eye (not shown). OR fractures (b) and pinwheels (d) tend to occur near the centers of OD stripes and receive connections primarily from the same eye preference. Saddle points (c) can occur either in the middle or near the boundaries of OD stripes, and thus can have either monocular or binocular connection patterns; the example neuron is in a monocular OD region and connects primarily to the left eye. These connection patterns further extend the predictions from Figure 5.12, showing how the connection patterns are shared between the OD and OR maps.