Systemic Review on Transcranial Electrical Stimulation Parameters and EEG/fNIRS Features for Brain Diseases

Abstract

BackgroundBrain disorders are gradually becoming the leading cause of death worldwide. However, the lack of knowledge of brain disease’s underlying mechanisms and ineffective neuropharmacological therapy have led to further exploration of optimal treatments and brain monitoring techniques.ObjectiveThis study aims to review the current state of brain disorders, which utilize transcranial electrical stimulation (tES) and daily usable noninvasive neuroimaging techniques. Furthermore, the second goal of this study is to highlight available gaps and provide a comprehensive guideline for further investigation.MethodA systematic search was conducted of the PubMed and Web of Science databases from January 2000 to October 2020 using relevant keywords. Electroencephalography (EEG) and functional near-infrared spectroscopy were selected as noninvasive neuroimaging modalities. Nine brain disorders were investigated in this study, including Alzheimer’s disease, depression, autism spectrum disorder, attention-deficit hyperactivity disorder, epilepsy, Parkinson’s disease, stroke, schizophrenia, and traumatic brain injury.ResultsSixty-seven studies (1,385 participants) were included for quantitative analysis. Most of the articles (82.6%) employed transcranial direct current stimulation as an intervention method with modulation parameters of 1 mA intensity (47.2%) for 16–20 min (69.0%) duration of stimulation in a single session (36.8%). The frontal cortex (46.4%) and the cerebral cortex (47.8%) were used as a neuroimaging modality, with the power spectrum (45.7%) commonly extracted as a quantitative EEG feature.ConclusionAn appropriate stimulation protocol applying tES as a therapy could be an effective treatment for cognitive and neurological brain disorders. However, the optimal tES criteria have not been defined; they vary across persons and disease types. Therefore, future work needs to investigate a closed-loop tES with monitoring by neuroimaging techniques to achieve personalized therapy for brain disorders.

Effect of Transcranial Pulsed Current Stimulation on Fatigue Delay after Medium-Intensity Training

“…Ninety participants were randomly divided into two groups, with fourty-five participants in each group, and they received true or sham (controls) stimulation of tPCS. In this study, we referred to the research paradigm of Yang et al on TES stimulation parameters [ 23 ]. The stimulation time of tPCS was set to 15 min and the stimulation intensity was set to 1.5 mA.…”

Neuromodulation in 2035

“…The proposed mechanism is that neural activity is promoted by the current flow under one electrode, and is inhibited under the second 18 ; clinical applications are being explored in rehabilitation, neuropsychiatry, epilepsy, and memory enhancement. 19,20 A derivative of this technique is transcranial alternating current stimulation (tACS). tACS provides a variable excitation waveform that can mimic natural brain rhythms such as the theta band (;4 Hz) associated with memory, create high-frequency impulses for blocking pain, or explore the effect on dynamic motor systems.…”

The application and perspective of hyperbaric oxygen therapy in acute ischemic stroke: From the bench to a starter?

“…Second, the way of assessing the effect of HBOT needs to be updated. Compared to the traditional clinical function score and the infarct size, functional MRI (fMRI), quantitative electroencephalogram (qEEG), and other responses to neurological function indicators can be used (47). In the study by Cevolani et al, fMRI was first used to evaluate HBOT functional effects on the central nervous system (CNS) of patients with strokes, suggesting a possible role of fMRI in revealing functional neuronal correlates of neuronal plasticity and HBOT-related neoangiogenesis (48).…”