Lookup NU author(s): Dr Will Sedley,
Dr Manon Grube,
Professor Tim Griffiths
This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).
© 2017 The Author(s). Perception relies on the integration of sensory information and prior expectations. Here we show that selective neurodegeneration of human frontal speech regions results in delayed reconciliation of predictions in temporal cortex. These temporal regions were not atrophic, displayed normal evoked magnetic and electrical power, and preserved neural sensitivity to manipulations of sensory detail. Frontal neurodegeneration does not prevent the perceptual effects of contextual information; instead, prior expectations are applied inflexibly. The precision of predictions correlates with beta power, in line with theoretical models of the neural instantiation of predictive coding. Fronto-temporal interactions are enhanced while participants reconcile prior predictions with degraded sensory signals. Excessively precise predictions can explain several challenging phenomena in frontal aphasias, including agrammatism and subjective difficulties with speech perception. This work demonstrates that higher-level frontal mechanisms for cognitive and behavioural flexibility make a causal functional contribution to the hierarchical generative models underlying speech perception.
Author(s): Cope TE, Sohoglu E, Sedley W, Patterson K, Jones PS, Wiggins J, Dawson C, Grube M, Carlyon RP, Griffiths TD, Davis MH, Rowe JB
Publication type: Article
Publication status: Published
Journal: Nature Communications
Online publication date: 18/12/2017
Acceptance date: 27/10/2017
ISSN (electronic): 2041-1723
Publisher: Nature Publishing Group
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