Experimental Setup for the Systematic Investigation of Infrared Neural Stimulation (INS)

Infrared neural stimulation (INS) gains growing interest both in electrophysiological research and for potential clinical applications, promising advantages like contactless operation, superior focality and hence spatial selectivity, and lack of electrical stimulation artifacts for nerve stimulation. We established an experimental setup for systematic investigation of relevant INS parameters, since little quantitative research for deeper understanding has been performed yet. Our customized setup facilitates the use of multiple fiber-based infrared laser systems of different wavelengths for remote stimulation, multi-site low-noise EMG recording and automated laser beam characterization. Hence, this setup simplifies upcoming systematic studies on both technical and physiological conditions for laser-induced neural activation. Determination of safe margins for reliable stimulation will help to understand the underlying physiological mechanisms and establish INS as alternative method for neural activation. Here, we present our experimental setup and preliminary results of our ongoing work.