Objective: Quantitative Electroencephalography (qEEG) can capture changes in brain activity following stroke. qEEG metrics traditionally focus on oscillatory activity, however recent findings highlight the importance of aperiodic (power-law) structure in characterizing pathological brain states. We assessed neurophysiological alterations and recovery after mono-hemispheric stroke by means of the Spectral Exponent (SE), a metric that reflects EEG slowing and quantifies the power-law decay of the EEG Power Spectral Density (PSD).Methods: Eighteen patients (n = 18) with mild to moderate mono-hemispheric Middle Cerebral Artery (MCA) ischaemic stroke were retrospectively enrolled for this study. Patients underwent EEG recording in the sub-acute phase (T0) and after 2 months of physical rehabilitation (T1). Sixteen healthy controls (HC; n = 16) matched by age and sex were enrolled as a normative group. SE values and narrow-band PSD were estimated for each recording. We compared SE and band-power between patients and HC, and between the affected (AH) and unaffected hemisphere (UH) at T0 and T1 in patients.Results: At T0, stroke patients showed significantly more negative SE values than HC (p = 0.003), reflecting broad-band EEG slowing. Most important, in patients SE over the AH was consistently more negative compared to the UH and showed a renormalization at T1. This SE renormalization significantly correlated with National Institute of Health Stroke Scale (NIHSS) improvement (R = 0.63, p = 0.005). Conclusions: SE is a reliable readout of the neurophysiological and clinical alterations occurring after an ischaemic cortical lesion. Significance: SE promise to be a robust method to monitor and predict patients' functional outcome.(c) 2022 International Federation of Clinical Neurophysiology.

EEG spectral exponent as a synthetic index for the longitudinal assessment of stroke recovery / J. Lanzone, M.A. Colombo, S. Sarasso, F. Zappasodi, M. Rosanova, M. Massimini, V.D. Lazzaro, G. Assenza. - In: CLINICAL NEUROPHYSIOLOGY. - ISSN 1388-2457. - 137:(2022 May), pp. 92-101. [10.1016/j.clinph.2022.02.022]

EEG spectral exponent as a synthetic index for the longitudinal assessment of stroke recovery

S. Sarasso;M. Rosanova;M. Massimini;
2022

Abstract

Objective: Quantitative Electroencephalography (qEEG) can capture changes in brain activity following stroke. qEEG metrics traditionally focus on oscillatory activity, however recent findings highlight the importance of aperiodic (power-law) structure in characterizing pathological brain states. We assessed neurophysiological alterations and recovery after mono-hemispheric stroke by means of the Spectral Exponent (SE), a metric that reflects EEG slowing and quantifies the power-law decay of the EEG Power Spectral Density (PSD).Methods: Eighteen patients (n = 18) with mild to moderate mono-hemispheric Middle Cerebral Artery (MCA) ischaemic stroke were retrospectively enrolled for this study. Patients underwent EEG recording in the sub-acute phase (T0) and after 2 months of physical rehabilitation (T1). Sixteen healthy controls (HC; n = 16) matched by age and sex were enrolled as a normative group. SE values and narrow-band PSD were estimated for each recording. We compared SE and band-power between patients and HC, and between the affected (AH) and unaffected hemisphere (UH) at T0 and T1 in patients.Results: At T0, stroke patients showed significantly more negative SE values than HC (p = 0.003), reflecting broad-band EEG slowing. Most important, in patients SE over the AH was consistently more negative compared to the UH and showed a renormalization at T1. This SE renormalization significantly correlated with National Institute of Health Stroke Scale (NIHSS) improvement (R = 0.63, p = 0.005). Conclusions: SE is a reliable readout of the neurophysiological and clinical alterations occurring after an ischaemic cortical lesion. Significance: SE promise to be a robust method to monitor and predict patients' functional outcome.(c) 2022 International Federation of Clinical Neurophysiology.
EEG; qEEG; Rehabilitation; Stroke;
Settore BIO/09 - Fisiologia
Settore MED/26 - Neurologia
   Human Brain Project Specific Grant Agreement 3 (HBP SGA3)
   HBP SGA3
   EUROPEAN COMMISSION
   H2020
   945539
mag-2022
8-mar-2022
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/916632
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