PSYCHOPHYSICS OF MOTION ADAPTATION PARALLELS INSECT ELECTROPHYSIOLOGY

We investigate the form and time course of motion adaptation, comparin g the psychophysical performance of human subjects with existing elect rophysiological data on insect vision, In the H1 neuron of the fly, th e response to a maintained motion stimulus is known to decrease over t ime while sensitivity to variations in speed around the maintained lev el increases [1]. This behaviour can be modelled by modifying a correl ation-based motion detector to include adaptable temporal filters (Fig . 1) [2]. We find that the form and time course of sensitivity changes in human motion perception are comparable to fly vision. We propose t hat, in both cases, adaptation serves to improve the transmission of n ovel motion information along the visual pathways at the expense of ma intaining an accurate representation of the unchanging components of t he stimulus. (C) Current Biology Lid ISSN 0960-9822