The role of action in sensation: evidence from colour perception

For proponents of the sensorimotor approach to perception consciousness is not amp;amp;lsquo;generatedamp;amp;lsquo; by passive reception of information on sensors or by neural excitation. Instead, phenomenal experience occurs when an agent interacts with its environment, involving its body in mastered active exploration. Action-sensation coupling is therefore a necessary condition for perception, even in cases such as colour vision, where the coupling is often implicit and eye movements are not necessary at any given moment to perceive. Thus, colour sensation could be defined by the specific coupling between eye movements and transformations in cone excitation. Using left-field blue / right-field yellow spectacles. we introduced an artificial regularity between eye movements and colour changes. Perceptual learning of the new sensory motor contingency was obtained in 40 minutes, inducing a dependency of colour judgement on the direction of eye movement. A second compute r-contro lled exp eriment confirmed these results for luminance judgement after 20 minutes of exposure. Our experiments established clearly the necessity of eye movement for perceptual learning and argue for the constitutive role of action in the genesis of colour sensation