Determination of optimal injection current pattern for multichannel transcranial electrical stimulation without...

Area of Science:

• Neuroscience
• Biomedical Engineering
• Medical Imaging

Background:

• Multichannel transcranial electrical stimulation (tES) relies on optimized current patterns for focal stimulation.
• Individual magnetic resonance images (MRIs) create accurate finite element (FE) head models but are often inaccessible.
• Standard head models offer a less accurate alternative due to anatomical variations.

Purpose of the Study:

• To develop a novel approach for determining tES injection current patterns using multiple head models.
• To enhance stimulation focality in multichannel tES without individual MRIs.
• To compare the efficacy of a multi-model approach against single standard models.

Main Methods:

• Optimized injection current patterns using 20 FE head models for three cortical targets.
• Averaged individual patterns to create a mean injection current pattern for each target.
• Evaluated stimulation focality using mean, individual, and standard model current patterns.

Main Results:

• The mean current pattern significantly improved stimulation focality compared to a standard head model.
• A minimum of 13 head models are necessary to achieve superior focality.
• The multi-model approach demonstrated enhanced stimulation accuracy.

Conclusions:

• Employing multiple head models is a practical strategy to boost multichannel tES efficacy.
• This method provides a viable alternative when individual MRI data is not obtainable.
• Improved stimulation focality can be achieved without compromising accuracy.