Analog VLSI implementation of a visual interneuron: enhanced sensory processing through biophysical modeling

Abstract

Journal ArticleFlies are capable of rapid, coordinated flight through unstructured environments. This flight is guided by visual motion information that is extracted from photoreceptors in a robust manner. One feature of the fly's visual processing that adds to this robustness is the saturation of wide-fi_x000C_eld motion-sensitive neuron responses with increasing pattern size. This makes the cell's responses less dependent on the sparseness of the optical ow fi_x000C_eld while retaining motion information. By implementing a compartmental neuronal model in silicon, we add this "gain control" to an existing analog VLSI model of fly vision. This results in enhanced performance in a compact, low-power CMOS motion sensor. Our silicon system also demonstrates that modern, biophysically-detailed models of neural sensory processing systems can be instantiated in VLSI hardware