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Alpha/beta power decreases track the fidelity of stimulus-specific information.

ABSTRACT: Massed synchronised neuronal firing is detrimental to information processing. When networks of task-irrelevant neurons fire in unison, they mask the signal generated by task-critical neurons. On a macroscopic level, such synchronisation can contribute to alpha/beta (8-30 Hz) oscillations. Reducing the amplitude of these oscillations, therefore, may enhance information processing. Here, we test this hypothesis. Twenty-one participants completed an associative memory task while undergoing simultaneous EEG-fMRI recordings. Using representational similarity analysis, we quantified the amount of stimulus-specific information represented within the BOLD signal on every trial. When correlating this metric with concurrently-recorded alpha/beta power, we found a significant negative correlation which indicated that as post-stimulus alpha/beta power decreased, stimulus-specific information increased. Critically, we found this effect in three unique tasks: visual perception, auditory perception, and visual memory retrieval, indicating that this phenomenon transcends both stimulus modality and cognitive task. These results indicate that alpha/beta power decreases parametrically track the fidelity of both externally-presented and internally-generated stimulus-specific information represented within the cortex.

SUBMITTER: Griffiths BJ

PROVIDER: S-EPMC6904219 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Alpha/beta power decreases track the fidelity of stimulus-specific information.

Griffiths Benjamin James BJ Mayhew Stephen D SD Mullinger Karen J KJ Jorge João J Charest Ian I Wimber Maria M Hanslmayr Simon S

eLife 20191129

Massed synchronised neuronal firing is detrimental to information processing. When networks of task-irrelevant neurons fire in unison, they mask the signal generated by task-critical neurons. On a macroscopic level, such synchronisation can contribute to alpha/beta (8-30 Hz) oscillations. Reducing the amplitude of these oscillations, therefore, may enhance information processing. Here, we test this hypothesis. Twenty-one participants completed an associative memory task while undergoing simultan ...[more]

PMID: 31782730

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Alpha/beta power decreases track the fidelity of stimulus-specific information.

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Alpha/beta power decreases track the fidelity of stimulus-specific information.

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