A Safe and Artefact Free Device for Monitoring Galvanic Skin Conductance During FMRI

Peter Erhard¹, Dieter Leibfritz¹

We developed a device for measuring galvanic skin response (GSR) during functional magnetic resonance imaging (fMRI). The goal was to prevent the volunteer from the risk of electric stimulation due to gradient induced currents into the leads of the device. This was achieved by inserting photo electronic switches into the leads close to the electrodes. These switches are turned off during gradient switching. As GSR data is only acquired during quiet periods, no additional filtering was implemented. First tests show efficient protection from electric stimulation. However the GSR signal is still contaminated by physiological noise and minor gradient cross talk.