based online NVC/CVR monitoring tool towards delivery of non-invasive brain stimulation is proposed. SUMMARY. Cortical neural activity can be modulated ...
Development of an EEG-fNIRS based online monitoring tool towards delivery of non-invasive brain stimulation Anirban Dutta, Mark Muthalib, Shubhajit Roy Chowdhury, David Guiraud, Michael A. Nitsche, Stephane Perrey
Abstract—A method for electroencephalography (EEG)functional near-infrared spectroscopy (fNIRS) based monitoring of cerebrobascular reactivity (CVR) and neurovascular coupling (NVC) during anodal transcranial direct current stimulation (tDCS) is presented. A case study on an able-bodied volunteer showed that our tDCS-fNIRS/EEG platform can characterize the “online” and “offline” effects of 2-mA tDCS modulation in both electrophysiological (EEG) and haemodynamic (fNIRS) components. Therefore, an EEG-fNIRS based online NVC/CVR monitoring tool towards delivery of non-invasive brain stimulation is proposed.
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SUMMARY Cortical neural activity can be modulated with tDCS [1]. During cortical neural activity, the electric currents from all excitable membranes of brain tissue superimpose in the extracellular medium and generate EEG. Neural activity has been shown to be closely related, spatially and temporally, to cerebral blood flow (CBF) that supplies glucose via neurovascular coupling (NVC) [2]. Here, cerebrovascular reactivity (CVR) is the change in CBF in response to NVC stimulus where its hemodynamic component can be captured by functional near-infrared spectroscopy (fNIRS). fNIRS (Oxymon MK III, Artinis Medical Systems) provided continuous monitoring of cerebral oxygenation and blood volume with high temporal resolution. We presented EEGfNIRS based monitoring of NVC/CVR under perturbation with tDCS [3] where initial dip in the oxy-haemoglobin concentration and concomitant increase in the mean power spectral density within lower (
