Beyond homogeneity: Charting the landscape of heterogeneity in psychiatric electroencephalography

Ebadi, A.; Allouch, S.; Mheich, A.; Tabbal, J.; Kabbara, A.; Robert, G.; Lefebvre, A.; Iftimovici, A.; Rodriguez-Herreros, B.; Chabane, N.; HASSAN, M.

doi:10.1101/2024.03.04.583393

bioRxiv · 10.1101/2024.03.04.583393

Beyond homogeneity: Charting the landscape of heterogeneity in psychiatric electroencephalography

Ebadi, A.·Allouch, S.·Mheich, A.·Tabbal, J.·Kabbara, A.·Robert, G.·Lefebvre, A.·Iftimovici, A.·Rodriguez-Herreros, B.·Chabane, N.·HASSAN, M.

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Abstract

Electroencephalography (EEG) has been thoroughly studied for decades in psychiatry research. Yet its integration into clinical practice as a diagnostic/prognostic tool remains unachieved. We hypothesize that a key reason is the underlying patients heterogeneity, overlooked in psychiatric EEG research relying on a case-control approach. We combine HD-EEG with normative modeling to quantify this heterogeneity using two well-established and extensively investigated EEG characteristics -spectral power and functional connectivity-across a cohort of 1674 patients with attention-deficit/hyperactivity disorder, autism spectrum disorder, learning disorder, or anxiety, and 560 matched controls. Normative models showed that deviations from population norms among patients were highly heterogeneous and frequency-dependent. Deviation spatial overlap across patients did not exceed 40% and 24% for spectral and connectivity, respectively. Considering individual deviations in patients has significantly enhanced comparative analysis, and the identification of patient-specific markers has demonstrated a correlation with clinical assessments, representing a crucial step towards attaining precision psychiatry through EEG.

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Ebadi, A., Allouch, S., Mheich, A., Tabbal, J., Kabbara, A., Robert, G., Lefebvre, A., Iftimovici, A., Rodriguez-Herreros, B., Chabane, N., HASSAN, M.. 2024-03-08. Beyond homogeneity: Charting the landscape of heterogeneity in psychiatric electroencephalography. https://doi.org/10.1101/2024.03.04.583393

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