Using bioimpedance spectroscopy parameters as real-time feedback during tDCS.

Area of Science:

• Neuroscience
• Biomedical Engineering
• Medical Physics

Background:

• Transcranial Direct Current Stimulation (tDCS) shows promise for neurological disorders but lacks reliable efficacy indicators.
• Current tDCS monitoring relies on easily measured but difficult-to-interpret voltage changes.

Purpose of the Study:

• To explore the feasibility of using BioImpedance Spectroscopy (BIS) parameters as real-time feedback during tDCS.
• To establish BIS as a potential indicator for monitoring and personalizing tDCS treatment.

Main Methods:

• An exploratory analysis was conducted using BIS parameters measured on the scalp during tDCS.
• BIS spectra were fitted to an equivalent electrical circuit model to extract parameters.
• A quadratic regression model was developed to predict DC voltage based on BIS parameters.

Main Results:

• BIS parameters are associated with applied DC voltage and reflect head tissue conductivity and capacitance.
• A quadratic regression model successfully predicted DC voltage using extracted BIS parameters.
• BIS measurements are cost-effective, safe, and do not interfere with tDCS.

Conclusions:

• BioImpedance Spectroscopy (BIS) shows potential as a real-time monitoring tool for Transcranial Direct Current Stimulation (tDCS).
• BIS parameters offer interpretable feedback related to tissue properties, enabling potential adjustments to tDCS protocols.
• This approach could lead to personalized tDCS treatments for neurological conditions.