Motion Detection for Reflexive Tracking

摘要: The moving observer who looks in the direction of heading experiences radial optic flow, which is known to elicit horizontal vergence eye movements at short latency, expansion causing convergence and contraction divergence: Radial Flow Vergence Response (RFVR). off one side linear version latency: Ocular Following (OFR). Although RFVR OFR are very different kinds movement sensitive patterns global motion, they have similar local spatiotemporal properties. For example, both responses critically dependent on Fourier composition motion stimuli, consistent with early spatio-temporal filtering prior detection, as well-known energy model analysis. When stimuli sine-wave gratings, two share a dependence spatial frequency contrast those even quantitative details similar. consists single step (“two-frame movie”) then brief inter-stimulus interval results reversal responses, idea that mediated by detectors receive visual input whose temporal impulse response function strongly biphasic. Further, when confronted gratings differ slightly competing motions, show nonlinear relative contrasts gratings: sine waves more than about an octave higher completely dominates lower loses its influence: winner-take-all. It has been suggested these interactions result from mutual inhibition between low-level mechanisms sensing harmonics. Lastly, unit recordings lesions monkeys suggest types neurons MT/MST region cerebral cortex flow. We will argue various findings all acquire their properties level MT/MST, where respond large-field shared common earlier stage, striate cortex, energy.