Objective: Large-scale connectivity, especially interhemispheric connections, plays a crucial role for recovery after stroke. Here we used methods from information theory to characterize interhemispheric information flow in wake- and sleep-EEG after cerebral ischemia.Methods:34 patients with unilateral ischemic stroke were included. Symbolic Transfer Entropy (STE) was applied between bipolar EEG signals on the left and the right cerebral hemisphere during polysomnographic recordings in the acute phase and 3 months after stroke.Results:In the acute phase, we found a sleep stage-dependent preferred interhemispheric asymmetry: during non-REM sleep the information flow was predominantly directed from the contralesional toward the ipsilesional hemisphere. This effect was greatly reduced in a follow-up recording 3 months after stroke onset.Conclusion: Our findings are consistent with functional imaging studies showing a transient hyperactivity of contralesional areas after stroke. We conclude that STE is a robust method for detecting post-stroke connectivity reorganizations, and that sleep stages have to be taken into account when assessing functional connectivity.Significance EEG is more widely available than functional MRI. Future studies will have to confirm whether EEG derived STE can be useful in a clinical setting during rehabilitation after stroke. (C) 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Stroke causes a transient imbalance of interhemispheric information flow in EEG during non-REM sleep

Nobili L;
2018-01-01

Abstract

Objective: Large-scale connectivity, especially interhemispheric connections, plays a crucial role for recovery after stroke. Here we used methods from information theory to characterize interhemispheric information flow in wake- and sleep-EEG after cerebral ischemia.Methods:34 patients with unilateral ischemic stroke were included. Symbolic Transfer Entropy (STE) was applied between bipolar EEG signals on the left and the right cerebral hemisphere during polysomnographic recordings in the acute phase and 3 months after stroke.Results:In the acute phase, we found a sleep stage-dependent preferred interhemispheric asymmetry: during non-REM sleep the information flow was predominantly directed from the contralesional toward the ipsilesional hemisphere. This effect was greatly reduced in a follow-up recording 3 months after stroke onset.Conclusion: Our findings are consistent with functional imaging studies showing a transient hyperactivity of contralesional areas after stroke. We conclude that STE is a robust method for detecting post-stroke connectivity reorganizations, and that sleep stages have to be taken into account when assessing functional connectivity.Significance EEG is more widely available than functional MRI. Future studies will have to confirm whether EEG derived STE can be useful in a clinical setting during rehabilitation after stroke. (C) 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.
File in questo prodotto:
File Dimensione Formato  
Stroke causes a transient imbalance of interhemispheric informationflow in EEG during non-REM sleep.pdf

accesso chiuso

Tipologia: Documento in versione editoriale
Dimensione 781.74 kB
Formato Adobe PDF
781.74 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11567/927637
Citazioni
  • ???jsp.display-item.citation.pmc??? 3
  • Scopus 11
  • ???jsp.display-item.citation.isi??? 10
social impact