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Simultaneous EEG Monitoring During Transcranial Direct Current Stimulation
Published on: June 17, 2013
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Local effective connectivity changes after transcranial direct current stimulation in obsessive-compulsive disorder
Hanyang Ruan1, Daniela Rodriguez Manrique2, Chelsea Winkelmann1
1School of Medicine and Health, Department of Diagnostic and Interventional Neuroradiology, Technical University of Munich, Munich, Germany; School of Medicine and Health, TUM-NIC Neuroimaging Center, Technical University of Munich, Munich, Germany.
Journal of Affective Disorders
|January 13, 2025
Summary
Transcranial direct current stimulation (tDCS) enhanced local brain network connectivity in the sensorimotor network (SMN) for individuals with obsessive-compulsive disorder (OCD). This suggests tDCS may help normalize brain activity in OCD patients.
Area of Science:
- Neuroscience
- Psychiatry
- Medical Imaging
Background:
- Obsessive-compulsive disorder (OCD) is characterized by altered brain network connectivity.
- The sensorimotor network (SMN) plays a role in OCD pathophysiology.
- Non-invasive brain stimulation techniques like tDCS are being explored for therapeutic potential in OCD.
Purpose of the Study:
- To investigate the effects of transcranial direct current stimulation (tDCS) on brain network connectivity in patients with OCD.
- To determine if tDCS targeting the right pre-supplementary motor area (pre-SMA) can modulate effective connectivity within the brain.
Main Methods:
- A randomized, double-blind, sham-controlled study involving 43 OCD patients.
- Anodal tDCS applied to the right pre-SMA with a cathodal reference on the left pre-SMA (2 mA).
- Resting-state functional MRI (fMRI) and regression dynamic causal modelling (rDCM) analyzed effective connectivity (EC) and graph theory metrics.
Main Results:
- Single-session tDCS significantly altered local effective connectivity within the SMN compared to sham.
- Active tDCS led to increased recruitment level, clustering coefficient, and local efficiency in the SMN.
- No significant changes were observed in global network connectivity.
Conclusions:
- A single tDCS session can effectively modulate local effective connectivity within the SMN in individuals with OCD.
- tDCS targeting the SMN may offer a potential intervention for normalizing altered brain network connectivity in OCD.
- Further research is needed to determine the long-term effects of tDCS in OCD.
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