Contour integration and cortical processing

Our understanding of visual processing in general, and contour integration in particular, has undergone great change over the last 10 years. There is now all accumulation of psychophysical and neurophysiological evidence that the outputs of Cells With conjoint orientation preference and spatial position are integrated in the process of explication Of rudimentary contours. Recent neuroanatomical and neurophysiological results Suggest that this process takes place at the cortical level V1. The code for contour integration may be a temporal one in that it may only manifest itself in the latter part of the spike train as a result of feedback and lateral interactions. Here we review some of the properties Of contour integration from a psychophysical perspective and we speculate oil their underlying neurophysiological substrate. (C) 2003 Elsevier Ltd. All rights reserved.