'Mixing in' afterimage colors

Item does not contain fulltextColoured stimuli may reveal different afterimage colours at the same retinal location, depending on surface contours presented after the image (Van Lier and Vergeer, 2007 Perception 36 200 - 201). Here we demonstrate that the filling-in of the afterimage colour depends on the colours that are presented inside and outside these contours. In the experiment, a composite star-like pattern alternated with the outline of one of its two component star-like shapes. The composite pattern was coloured, except the central area--which was grey. The component shapes were completely grey. The colours were drawn from the set of 'Teufel colours'. The participants matched the afterimage colour in the central area of the component shape (which coincided with the central grey area of the previously presented composite pattern) with Teufel-colour patches. The results show that the perceived afterimage colour is a mixture of filled-in afterimage colours, based on the--previously presented--colour outside the component shape and the complementary colour of the colour inside that shape.1 p