title: Corticospinal excitability changes to anodal tDCS elucidated with NIRS-EEG joint-imaging: An ischemic stroke study.
abstract: Transcranial direct current stimulation (tDCS) has been shown to modulate corticospinal excitability. We used near-infrared spectroscopy (NIRS)-electroencephalography (EEG) joint-imaging during and after anodal tDCS to measure changes in mean cerebral haemoglobin oxygen saturation (rSO2) along with changes in the log-transformed mean-power of EEG within 0.5 Hz-11.25 Hz. In two separate studies, we investigated local post-tDCS alterations from baseline at the site of anodal tDCS using NIRS-EEG/tDCS joint-imaging as well as local post-tDCS alterations in motor evoked potentials (MEP)-measure of corticospinal excitability. In the first study, we found that post-tDCS changes in the mean rSO2 from baseline mostly correlated with the corresponding post-tDCS change in log-transformed mean-power of EEG within 0.5 Hz-11.25 Hz. Moreover, a decrease in log-transformed mean-power of EEG within 0.5 Hz-11.25 Hz corresponded with an increase in the MEP-measure of corticospinal excitability--found in the second study. Therefore, we propose to combine NIRS-EEG/tDCS joint-imaging with corticospinal excitability investigation in a single study to confirm these finding. Furthermore, we postulate that the innovative technologies for portable NIRS-EEG neuroimaging may be leveraged to objectively quantify the progress (e.g., corticospinal excitability alterations) and dose tDCS intervention as an adjuvant treatment during neurorehabilitation.
authors.forename: Utkarsh
authors.initials: U
authors.lastname: Jindal
authors.forename: Mehak
authors.initials: M
authors.lastname: Sood
authors.forename: Shubhajit Roy
authors.initials: SR
authors.lastname: Chowdhury
authors.forename: Abhijit
authors.initials: A
authors.lastname: Das
authors.forename: Daniel
authors.initials: D
authors.lastname: Kondziella
authors.forename: Anirban
authors.initials: A
authors.lastname: Dutta
mesh_terms: D000368:Aged; D002545:Brain Ischemia / Q000534:rehabilitation*; D004566:Electrodes; D004569:Electroencephalography / Q000295:instrumentation / Q000379:methods*; D019054:Evoked Potentials, Motor / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008962:Models, Theoretical; D019265:Spectroscopy, Near-Infrared; D000071939:Stroke Rehabilitation; D065908:Transcranial Direct Current Stimulation / Q000295:instrumentation / Q000379:methods*