Journal article

Publication year: 2007

Pages: 3385-3393

Journal: Vision Research

Volume number: 47

Issue number: 27

ISSN: 0042-6989

eISSN: 1878-5646

Open access status: Green

DOI Link: https://doi.org/10.1016/j.visres.2007.10.001

Publisher: Elsevier

Abstract: 
The Craik-O'Brien-Cornsweet effect (COCE) is a visual illusion in which a difference in brightness is observed between two regions of equal luminance separated by a contrast edge with opposite luminance gradients on each side. The COCE also occurs with chromatic contrasts. It has been hypothesized that the COCE is mediated by a cortical filling-in process. According to the filling-in hypothesis, the filling-in or spreading of neural activity proceeds at finite speed, and therefore exhibits some temporal tuning as a function of the width of the area to be filled in. In the present study, observers varied the temporal frequency of a COC grating to determine the maximum temporal frequency at which a temporal modulation of brightness or color was perceived. In the achromatic COCE, contours were modulated along the luminance axis of the DKL color space; in the chromatic COCE, contours were modulated either along the L - M or the S - (L + M) axis. For the achromatic condition, the critical temporal frequency at which the COCE was still perceived had the shape of an inverted U, inconsistent with the filling-in hypothesis: the critical temporal frequency increased with increasing spatial frequency only up to 0.2 cycles/deg, but then decreased for higher spatial frequencies. For the chromatic COCE, the critical temporal frequency decreased with increasing spatial frequency, which is also inconsistent with filling-in. Thus, the results of the present study are inconsistent with the idea that the temporal dynamics of the COCE, both achromatic and chromatic, are due to filling-in. Instead, our results are consistent with the spatial filtering properties of the luminance and chromatic systems. (C) 2007 Elsevier Ltd. All rights reserved.

Harvard Citation style: Devinck, F., Hansen, T. and Gegenfurtner, K. (2007) Temporal properties of the chromatic and achromatic Craik-O'Brien-Cornsweet effect, Vision Research, 47(27), pp. 3385-3393. https://doi.org/10.1016/j.visres.2007.10.001

APA Citation style: Devinck, F., Hansen, T., & Gegenfurtner, K. (2007). Temporal properties of the chromatic and achromatic Craik-O'Brien-Cornsweet effect. Vision Research. 47(27), 3385-3393. https://doi.org/10.1016/j.visres.2007.10.001