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Neural dynamics of perceptual inference and its reversal during imagery.

ABSTRACT: After the presentation of a visual stimulus, neural processing cascades from low-level sensory areas to increasingly abstract representations in higher-level areas. It is often hypothesised that a reversal in neural processing underlies the generation of mental images as abstract representations are used to construct sensory representations in the absence of sensory input. According to predictive processing theories, such reversed processing also plays a central role in later stages of perception. Direct experimental evidence of reversals in neural information flow has been missing. Here, we used a combination of machine learning and magnetoencephalography to characterise neural dynamics in humans. We provide direct evidence for a reversal of the perceptual feed-forward cascade during imagery and show that, during perception, such reversals alternate with feed-forward processing in an 11 Hz oscillatory pattern. Together, these results show how common feedback processes support both veridical perception and mental imagery.

SUBMITTER: Dijkstra N

PROVIDER: S-EPMC7371419 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Neural dynamics of perceptual inference and its reversal during imagery.

Dijkstra Nadine N Ambrogioni Luca L Vidaurre Diego D van Gerven Marcel M

eLife 20200720

After the presentation of a visual stimulus, neural processing cascades from low-level sensory areas to increasingly abstract representations in higher-level areas. It is often hypothesised that a reversal in neural processing underlies the generation of mental images as abstract representations are used to construct sensory representations in the absence of sensory input. According to predictive processing theories, such reversed processing also plays a central role in later stages of perceptio ...[more]

PMID: 32686645

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Dataset Information

Neural dynamics of perceptual inference and its reversal during imagery.

Publications

Neural dynamics of perceptual inference and its reversal during imagery.

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