Abstract
It is widely assumed that we must use predictions to determine the nature of our perceptual experiences. Work from the last few years suggests that supporting mechanisms operate via top-down modulations of sensory processing. However, theories within the domain of action concerning the operation of these mechanisms are at odds with those from other perceptual disciplines. Specifically, action theories propose that we cancel predicted events from perceptual processing to render our experiences informative - telling us what we did not already know. In contrast, theories outside of action - typically couched within Bayesian frameworks - demonstrate that we combine our predictions (priors) with the evidence (likelihood) to determine perception (posterior). Such functions are achieved via predictions sharpening processing in early sensory regions. In this talk I will present three fMRI studies from our lab that ask how these predictions really shape early visual processing. They will ask whether action predictions in fact shape visual processing differently from other types of prediction and about differences in representation across different cortical laminae. The studies compare processing of observed avatar movements and simple grating events, and ask about the information content associated with the stimulus types as well as signal level across different types of voxels. We can conclude that action expectations exhibit a similar sharpening effect on visual processing to other expectations, rendering our perception more veridical on average. Future work must now establish how we also use our predictions - across domains - to yield informative experiences.