HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) A corrigendum has been published All Versions of this Article: 96/6/3492    most recent 00575.2006v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (7) Citing Articles via Google Scholar Google Scholar Articles by David, S. V. Articles by Gallant, J. L. Search for Related Content PubMed PubMed Citation Articles by David, S. V. Articles by Gallant, J. L.

Spectral Receptive Field Properties Explain Shape Selectivity in Area V4

¹Graduate Group in Bioengineering, ²Department of Molecular and Cellular Biology, ³Department of Psychology, and ⁴Program in Neuroscience, University of California, Berkeley

Submitted 31 May 2006; accepted in final form 12 September 2006

Neurons in cortical area V4 respond selectively to complex visual patterns such as curved contours and non-Cartesian gratings. Most previous experiments in V4 have measured responses to small, idiosyncratic stimulus sets and no single functional model yet accounts for all of the disparate results. We propose that one model, the spectral receptive field (SRF), can explain many observations of selectivity in V4. The SRF describes tuning in terms of the orientation and spatial frequency spectrum and can, in principle, predict the response to any visual stimulus. We estimated SRFs for neurons in V4 of awake primates by linearized reverse correlation of responses to a large set of natural images. We find that V4 neurons have large orientation and spatial frequency bandwidth and often bimodal orientation tuning. For comparison, we estimated SRFs for neurons in primary visual cortex (V1). Consistent with previous observations, we find that V1 neurons have narrower bandwidth than that of V4. To determine whether estimated SRFs can account for previous observations of selectivity, we used them to predict responses to Cartesian gratings, non-Cartesian gratings, natural images, and curved contours. Based on these predictions, we find that the majority of neurons in V1 are selective for Cartesian gratings, whereas the majority of V4 neurons are selective for non-Cartesian gratings or natural images. The SRF describes visual tuning properties with a second-order nonlinear model. These results support the hypothesis that a second-order model is sufficient to describe the general mechanisms mediating shape selectivity in area V4.

This article has been cited by other articles:

				C. Cadieu, M. Kouh, A. Pasupathy, C. E. Connor, M. Riesenhuber, and T. Poggio A Model of V4 Shape Selectivity and Invariance J Neurophysiol, September 1, 2007; 98(3): 1733 - 1750. [Abstract] [Full Text] [PDF]