Figure 3.

A schematic representation of the parallel inputs to V5. The classical input (shown in red) reaches V5 through V1 with latencies of about 60 ms. The V1-by-passing input (green) delivers its signals at latencies of about 30 ms. Its critical involvement in the detection of fast motion becomes evident in patients suffering from the Riddoch Syndrome, whose motion vision is a much impoverished but conscious capacity to detect the direction of motion of fast moving stimuli. There are further parallel (cortical) inputs to V5 in the classical pathways, from V2 and V3 (gray); the feedback from V5 to V1 is shown in blue.