Dataset Information

Tonic somatosensory responses and deficits of tactile awareness converge in the parietal operculum.

ABSTRACT: Although clinical neuroscience and the neuroscience of consciousness have long sought mechanistic explanations of tactile-awareness disorders, mechanistic insights are rare, mainly because of the difficulty of depicting the fine-grained neural dynamics underlying somatosensory processes. Here, we combined the stereo-EEG responses to somatosensory stimulation with the lesion mapping of patients with a tactile-awareness disorder, namely tactile extinction. Whereas stereo-EEG responses present different temporal patterns, including early/phasic and long-lasting/tonic activities, tactile-extinction lesion mapping co-localizes only with the latter. Overlaps are limited to the posterior part of the perisylvian regions, suggesting that tonic activities may play a role in sustaining tactile awareness. To assess this hypothesis further, we correlated the prevalence of tonic responses with the tactile-extinction lesion mapping, showing that they follow the same topographical gradient. Finally, in parallel with the notion that visuotactile stimulation improves detection in tactile-extinction patients, we demonstrated an enhancement of tonic responses to visuotactile stimuli, with a strong voxel-wise correlation with the lesion mapping. The combination of these results establishes tonic responses in the parietal operculum as the ideal neural correlate of tactile awareness.

SUBMITTER: Del Vecchio M

PROVIDER: S-EPMC8719842 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Tonic somatosensory responses and deficits of tactile awareness converge in the parietal operculum.

Del Vecchio Maria M Fossataro Carlotta C Zauli Flavia Maria FM Sartori Ivana I Pigorini Andrea A d'Orio Piergiorgio P Abarrategui Belen B Russo Simone S Mikulan Ezequiel Pablo EP Caruana Fausto F Rizzolatti Giacomo G Garbarini Francesca F Avanzini Pietro P

Brain : a journal of neurology 20211201 12

Although clinical neuroscience and the neuroscience of consciousness have long sought mechanistic explanations of tactile-awareness disorders, mechanistic insights are rare, mainly because of the difficulty of depicting the fine-grained neural dynamics underlying somatosensory processes. Here, we combined the stereo-EEG responses to somatosensory stimulation with the lesion mapping of patients with a tactile-awareness disorder, namely tactile extinction. Whereas stereo-EEG responses present diff ...[more]

PMID: 34633436

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Dataset Information

Tonic somatosensory responses and deficits of tactile awareness converge in the parietal operculum.

Publications

Tonic somatosensory responses and deficits of tactile awareness converge in the parietal operculum.

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