Modulation of task-related cortical connectivity in the acute and subacute phase after stroke

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningfagfællebedømt

Lisbeth Hoejkjaer Larsen, Ivan Chrilles Zibrandtsen, Troels Wienecke, Troels Wesenberg Kjær, Henning Langberg, Jens Bo Nielsen, Mark Schram Christensen

The functional relevance of cortical reorganisation post-stroke is still not well understood. In this study we investigated task-specific modulation of cortical connectivity between neural oscillations in key motor regions during the early phase after stroke. EEG and EMG recordings were examined from 15 patients and 18 controls during a precision grip task using the affected hand. Each patient attended two sessions in the acute and subacute phase (median of 3 & 34 days) post-stroke. Dynamic causal modeling (DCM) for induced responses was used to investigate task-specific modulations of oscillatory couplings in a bilateral network comprising supplementary motor area (SMA), dorsal premotor cortex (PMd) and primary motor cortex (M1). Fourteen models were constructed for each subject and the input induced by the experimental manipulation (task) was set to inferior parietal lobule (IPL). Bayesian model selection favoured a fully connected model. A reduced coupling from SMA and intact M1 in the γ-band (31-48 Hz) to lesioned M1 in the β-band (15-30 Hz) was observed in patients in the acute phase compared to controls. Behavioral performance improved significantly in the subacute phase while an increased positive coupling from intact PMd to lesioned M1 and a less negative modulation from lesioned M1 to intact M1 were observed for patients compared to controls both from the γ-band to the β-band. We infer that the observed differences in cross-frequency cortical interactions are important for functional recovery. This article is protected by copyright. All rights reserved.

OriginalsprogEngelsk
TidsskriftEuropean Journal of Neuroscience
Vol/bind47
Udgave nummer8
Sider (fra-til)1024-1032
Antal sider9
ISSN0953-816X
DOI
StatusUdgivet - 2018

ID: 191289799