Page 305 - MEGIN Book Of Abstracts - 2023

CONCLUSIONS This study provides new information subacute stroke, when behavioural effects might be ex-
on the differential cortical activations modulated by pected to be greater, have been relatively unexplored.
bilateral and unilateral MT. Here, we examined the neurophysiological effects and
the factors influencing responsiveness of dual-tDCS in
SIGNIFICANCE Bilateral MT led to greater M1 neural subacute stroke survivors.
activities than unilateral MT and bilateral movements
without a mirror in stroke patients. METHODS We conducted a randomized sham-con-
trolled crossover study in 18 survivors with first-ever,
Keywords: Mirror therapy, Mirror visual feedback, Stroke, unilateral subcortical ischaemic stroke 2-4 weeks after
magnetoencephalography (MEG) stroke onset and 14 matched healthy controls. Partici-
pants had real dual-tDCS (with an ipsilesional [right for
Clinical neurophysiology: official journal of the controls] M1 anode and a contralesional M1 [left for
International Federation of Clinical Neurophysiology controls] cathode; 2 mA for 20mins) and sham dual-
(2020), Vol. 131, No. 10 (32828035) (6 citations) tDCS on separate days, with concurrent paretic [left for
controls] hand exercise. Using transcranial magnetic
stimulation (TMS) and magnetoencephalography
Neurophysiological signatures of hand motor (MEG), we recorded motor evoked potentials (MEPs),
response to dual-transcranial direct current the ipsilateral silent period (iSP), short-interval intracor-
stimulation in subacute stroke: a TMS and MEG tical inhibition, and finger movement-related cortical
study (2020) oscillations before and immediately after tDCS.

Kuo, I-Ju; Tang, Chih-Wei; Tsai, Yun-An; Tang, Shuen- RESULTS Stroke survivors had decreased excitability in
Chang; Lin, Chun-Jen; Hsu, Shih-Pin; Liang, Wei-Kuang; ipsilesional M1 with a relatively excessive transcallosal
Juan, Chi-Hung; Zich, Catharina; Stagg, Charlotte J; Lee, inhibition from the contralesional to ipsilesional hemi-
I-Hui sphere at baseline compared with controls, as quanti-
fied by decreased MEPs and increased iSP duration.
Department of Neurosurgery, Taipei Veterans General Dual-tDCS led to increased MEPs and decreased iSP
Hospital, No.201, Sec. 2, Shipai Rd., Beitou Dist, Taipei City, duration in ipsilesional M1. The magnitude of the tDCS-
112, Taiwan; Department of Neurology, Far Eastern Memo- induced MEP increase in stroke survivors was predicted
rial Hospital, No.21, Sec. 2, Nanya S. Rd., Banqiao Dist, New by baseline contralesional-to-ipsilesional transcallosal
Taipei City, 220, Taiwan; Division of Cerebrovascular Diseases, inhibition (iSP) ratio. Baseline post-movement syn-
Neurological Institute, Taipei Veterans General Hospital, chronization in α-band activity in ipsilesional M1 was
No.201, Sec. 2, Shipai Rd., Beitou Dist, Taipei City, 112, Taiwan; decreased after stroke compared with controls, and
Institute of Brain Science, Brain Research Center, National its tDCS-induced increase correlated with upper limb
Yang-Ming University, No.155, Sec. 2, Linong St., Beitou Dist, score in stroke survivors. No significant adverse effects
Taipei City, 112, Taiwan; Institute of Cognitive Neuroscience, were observed during or after dual-tDCS.
National Central University, No.300, Zhongda Rd., Zhongli
Dist, Taoyuan City, 320, Taiwan; MRC Brain Network Dynam- CONCLUSIONS Task-concurrent dual-tDCS in subacute
ics Unit, University of Oxford, Oxford, OX1 3TH, UK; Division stroke can safely and effectively modulate bilateral M1
of Cerebrovascular Diseases, Neurological Institute, Taipei excitability and inter-hemispheric imbalance and also
Veterans General Hospital, No.201, Sec. 2, Shipai Rd., Beitou movement-related α-activity.
Dist, Taipei City, 112, Taiwan. ihlee@vghtpe.gov.tw

BACKGROUND Dual transcranial direct current stimula-
tion (tDCS) to the bilateral primary motor cortices (M1s)
has potential benefits in chronic stroke, but its effects in

 ontents  Index 284
C