Action sharpens sensory representations of expected outcomes

Floris P De Lange,Clare Press,Sam J Gilbert,Daniel Yon

doi:10.1038/s41467-018-06752-7

Abstract

When we produce actions we predict their likely consequences. Dominant models of action control suggest that these predictions are used to ‘cancel’ perceptual processing of expected outcomes. However, normative Bayesian models of sensory cognition developed outside of action propose that rather than being cancelled, expected sensory signals are represented with greater fidelity (sharpened). Here, we distinguished between these models in an fMRI experiment where participants executed hand actions (index vs little finger movement) while observing movements of an avatar hand. Consistent with the sharpening account, visual representations of hand movements (index vs little finger) could be read out more accurately when they were congruent with action and these decoding enhancements were accompanied by suppressed activity in voxels tuned away from, not towards, the expected stimulus. Therefore, inconsistent with dominant action control models, these data show that sensorimotor prediction sharpens expected sensory representations, facilitating veridical perception of action outcomes.

Highlights

When we produce actions we predict their likely consequences
Activity should be suppressed only in units tuned away from expected inputs, rather than in units tuned towards these inputs as hypothesised by the cancellation account. In line with this account, Kok et al17. found that visual stimuli that were expected on the basis of a preceding tone evoked weaker responses in primary visual cortex (V1) primarily in voxels tuned away from the presented stimulus, and multivariate pattern analysis (MVPA) demonstrated a superior ability to decode the observed stimulus from activity patterns in this area
We adjudicated between these possibilities by requiring human participants to execute hand actions and simultaneously observe congruent or incongruent movements of an avatar hand, while recording neural activity using functional magnetic resonance imaging

Summary

Introduction

When we produce actions we predict their likely consequences. Dominant models of action control suggest that these predictions are used to ‘cancel’ perceptual processing of expected outcomes. If prediction sharpens populations towards expected outcomes, population responses will contain more information about observed hand movements on congruent trials and there will be reduced activation in units tuned away from the congruent stimulus.

Results

Conclusion