Evidence for a role of action in color perception

Action is not usually considered to play a role in colour perception. However, sensorimotor theories of perception (Gibson 1962; O’Regan and Noë 2002; Hurley 1998; Myin 2001) suggest that on the contrary the transformations created by action in sensory input are a necessary condition for all perception. In the case of colour vision, eye movements may explain how a retina with significant non-regularities in resolution and cone arrangement (Roorda and Williams 1999) could permit the perception of a richly colored world (Clark and O’Regan 2000; Skaf et al. 2002). We provide evidence that perception of color is modified when an artificial coupling is introduced linking eye movements and color changes. After 40 minutes of wearing left-field blue / right-field yellow spectacles, observers’ color vision adapts so that after removing the spectacles, white patches seem to become bluer when the eyes move rightwards and yellower when the eyes move leftwards. This induced dependency of color perception on the direction of eye saccade is shown to be dependent on the amount of eye movements during exposure. This result, which cannot be explained neither by retinal adaptation, nor by a conditioned association between color and side, constitute first clear evidence for a role of eye movements in perceived color and argue for the involvement in color perception of neural mechanisms continuously tuned to sensorimotor contingencies