THE INFLUENCE OF ADAPTATION ON PERCEIVED VISUAL LOCATION

We demonstrate a marked effect of prior adaptation upon the perceived position of subsequently presented stimuli using both first-order (lum inance-defined) and second-order (texture-defined) stimuli. The effect of varying the contrast of the adapting and test stimuli depends only upon the ratio of adapting/test contrast. Adaptation effects for the two types of stimuli differ in terms of interocular transfer and rate of decay. Whilst adapting and testing with the same type of stimulus ( first- or second-order) produces large shifts in perceived position, l ittle or no crossover effect was found. The data are accounted for by a model in which the centroid of the linear combination of after-image and test stimulus is extracted. (C) 1997 Elsevier Science Ltd.