Silicon Model of Motion Adaptation in the Fly Visual System
نویسنده
چکیده
We describe an adaptive version of the Hassenstein–Reichardt detector, which models direction-selective computation in the fly. The Hassenstein– Reichardt detector has a fixed time constant. However, several researchers have shown that the time constant of the fly’s motion system adapts to the temporal frequency or speed of the input. The time constant of our adaptive detector also adapts to the input frequencies, so that our detector can respond over a larger range of frequencies. The time constant of our system thus codes the time scale of the input frequencies. This adaptation property of the motion system allows the system to maintain high sensitivity to changes in velocity from the mean level. We show how our model is implemented in analog VLSI as part of a low-power silicon motion system, and we show measurements of the time-constant adaptation.
منابع مشابه
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