Multiplexing in the primate motion pathway

This article begins by reviewing recent work on 3D motion processing in the primate visual system. Some of these results suggest that 3D motion signals may be processed in the same circuitry already known to compute 2D motion signals. Such “multiplexing” has implications for the study of visual cortical circuits and neural signals. A more explicit appreciation of multiplexing-and the computations required for demultiplexing-may enrich the study of the visual system by emphasizing the importance of a structured and balanced “encoding/decoding” framework. In addition to providing a fresh perspective on how successive stages of visual processing might be approached, multiplexing also raises caveats about the value of “neural correlates” for understanding neural computation.

► Processing of visual motion in 3D depends on both disparity-based and velocity-based cues. ► Recent results suggest that the velocity-based cue is important. ► This processing appears to be multiplexed within the same circuitry as for 2D motion. ► Multiplexing may represent a general aspect of neural signaling. ► This perspective reinforces the importance of an encoding-decoding framework.