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Cortica

Literature Review

Vol. 4 No. 2 (2025): From synpatic pruning to educational neuroscience

États modifiés de la conscience : Revue systématique PRISMA et preuve de concept

  • Gowtham Karim Rajadurai
  • Cherine Fahim
  • Sophie Nicole
  • Chantal Martin Soelch
DOI
https://doi.org/10.26034/cortica.2025.8924
Submitted
December 8, 2025
Published
2025-12-15

Abstract

Contexte

La transe cognitive auto‑induite (TCAI) est un état volontaire d’absorption et d’hyperfocalisation attentionnelle, potentiellement utile pour moduler les réponses au trauma et certaines manifestations dissociatives. Pourtant, ses corrélats neurophysiologiques et ses retombées cliniques demeurent peu intégrés aux modèles actuels de psychotraumatologie.

Objectifs

(i) Synthétiser systématiquement, selon les recommandations PRISMA, les données comportementales et neurophysiologiques portant sur la TCAI et des transes apparentées ; (ii) examiner la faisabilité d’un enregistrement EEG portable à faible densité pour documenter les marqueurs oscillatoires de la TCAI chez des praticiennes expertes.

Méthode

Une recherche dans six bases de données a identifié 1 173 références ; après élimination des doublons et application des critères d’inclusion/exclusion, 13 études ont été retenues (accord inter‑juge κ = 0,87). Les mesures incluaient principalement l’EEG, mais aussi l’IRMf, la SPECT ou le TMS‑EEG. En parallèle, une preuve de concept EEG a été menée auprès de trois praticiennes formées à la TCAI (psychologue, infirmière en psychiatrie et art thérapeute), comparant un repos yeux ouverts à une auto‑induction (EMOTIV Insight casque sans fil, 5 électrodes).

Résultats

La revue met en évidence : (a) une augmentation de la puissance thêta, (b) des modulations des bandes alpha/bêta, et (c) des réorganisations de la connectivité (notamment DMN et réseaux fronto‑pariétaux). Ces patterns s’accompagnent phénoménologiquement d’absorption accrue, d’imagerie mentale vivace et d’une réduction de l’hypervigilance. Les données restent toutefois hétérogènes (protocoles, tailles d’échantillon, définitions de la transe), et la bande gamma apparaît moins consistante. Dans la preuve de concept, toutes les participantes ont montré une hausse marquée des ondes thêta ; une élévation gamma nette n’était observée que chez l’une d’elles.

Conclusion

Les résultats convergent pour identifier la bande thêta comme marqueur robuste des états de transe, tandis que les modulations gamma semblent plus idiosyncratiques. La faisabilité d’un EEG portable ouvre la voie à des protocoles d’auto‑régulation, susceptibles de compléter les approches psychothérapeutiques centrées sur la régulation émotionnelle, le trauma et la dissociation. Des études de plus grande envergure, multimodales, préenregistrées et contrôlées sont nécessaires pour préciser la spécificité neurophysiologique de la TCAI et son utilité clinique en psychotraumatologie.

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