Biomarker use in predicting transcranial direct-current stimulation (tDCS) response: a systematic scoping review

Area of Science:

• Neuroscience
• Neuromodulation
• Biomarker Discovery

Background:

• Trans-cranial Direct Current Stimulation (tDCS) is a non-invasive neuromodulation technique with growing evidence for treating neuropsychiatric conditions.
• Predictive and monitoring biomarkers are crucial for optimizing tDCS efficacy in clinical practice.

Purpose of the Study:

• To systematically review and identify biomarkers that can predict response to tDCS in patients with neuropsychiatric disorders.
• To highlight promising candidate biomarkers for future research and clinical application.

Main Methods:

• A systematic scoping review of MEDLINE and EMBASE databases was conducted.
• Studies were screened, and data extracted, with quality assessed using JADAD, MINORS, and Ottawa scales.
• Biomarkers with positive results in at least two studies across ten neuropsychiatric disorder categories were identified.

Main Results:

• Functional connectivity was the most frequently identified biomarker across 7 out of 10 disorder groups.
• Electroencephalography (EEG) features and cortical activation were also prominent biomarkers.
• Other identified biomarkers included anatomical features, clinical assessments, and neurotransmitter levels.

Conclusions:

• This review consolidates evidence for promising biomarkers to predict and monitor tDCS response in neuropsychiatric populations.
• The findings provide a foundation for future research to validate these biomarkers and improve personalized tDCS treatment.