Anatomical Characteristics Predict Response to Transcranial Direct Current Stimulation (tDCS): Development of a...

Area of Science:

• Neuroscience
• Biomedical Engineering
• Medical Imaging

Background:

• Transcranial direct current stimulation (tDCS) shows promise for neurological and psychological disorders.
• Inter-subject variability in tDCS after-effects limits treatment efficacy.
• Current fixed-dose methods neglect individual anatomical differences.

Purpose of the Study:

• To investigate how age and anatomical features (CSF volume, skull thickness, brain tissue composition) influence tDCS electric field distribution and cortical excitability.
• To develop a personalized approach for tDCS by accounting for individual patient morphology.

Main Methods:

• Computational modeling of electric field distribution using realistic head models from MRI scans of 23 adults and children.
• Analysis of correlations between anatomical variables and electric field strength.
• Identification of factors influencing tDCS responsiveness.

Main Results:

• Significant negative correlations were found between maximum electric field strength and anatomical parameters (p < 0.05).
• The percentage of brain tissue exposed to electric fields above 0.227 V/m was a key determinant of tDCS responsiveness.
• Multiple regression models were proposed for predicting patient response.

Conclusions:

• Individual anatomical variations significantly affect tDCS outcomes.
• Personalized tDCS, guided by computational models and patient-specific anatomy, can enhance treatment efficacy.
• Tailoring current intensity to individual morphology is essential for optimizing tDCS therapy.