Dataset Information

Lack of awareness despite complex visual processing: Evidence from event-related potentials in a case of selective metamorphopsia.

ABSTRACT: Visual awareness is thought to result from integration of low- and high-level processing; instances of integration failure provide a crucial window into the cognitive and neural bases of awareness. We present neurophysiological evidence of complex cognitive processing in the absence of awareness, raising questions about the conditions necessary for visual awareness. We describe an individual with a neurodegenerative disease who exhibits impaired visual awareness for the digits 2 to 9, and stimuli presented in close proximity to these digits, due to perceptual distortion. We identified robust event-related potential responses indicating 1) face detection with the N170 component and 2) task-dependent target-word detection with the P3b component, despite no awareness of the presence of faces or target words. These data force us to reconsider the relationship between neural processing and visual awareness; even stimuli processed by a workspace-like cognitive system can remain inaccessible to awareness. We discuss how this finding challenges and constrains theories of visual awareness.

SUBMITTER: Schubert TM

PROVIDER: S-EPMC7355000 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Lack of awareness despite complex visual processing: Evidence from event-related potentials in a case of selective metamorphopsia.

Schubert Teresa M TM Rothlein David D Brothers Trevor T Coderre Emily L EL Ledoux Kerry K Gordon Barry B McCloskey Michael M

Proceedings of the National Academy of Sciences of the United States of America 20200622 27

Visual awareness is thought to result from integration of low- and high-level processing; instances of integration failure provide a crucial window into the cognitive and neural bases of awareness. We present neurophysiological evidence of complex cognitive processing in the absence of awareness, raising questions about the conditions necessary for visual awareness. We describe an individual with a neurodegenerative disease who exhibits impaired visual awareness for the digits 2 to 9, and stimul ...[more]

PMID: 32571942

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Dataset Information

Lack of awareness despite complex visual processing: Evidence from event-related potentials in a case of selective metamorphopsia.

Publications

Lack of awareness despite complex visual processing: Evidence from event-related potentials in a case of selective metamorphopsia.

Similar Datasets

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