What can occur from referencing electrodes with dissimilar metals to each other?

When referencing electrodes made from dissimilar metals, a galvanic or electrochemical reaction can take place at the interface where the two metals meet. This occurs due to differences in electrode potentials, which can induce the generation of a small voltage. Depending on the skin's conductivity and other environmental factors, this reaction may lead to a galvanic skin response, which can manifest as a change in skin resistance or potentially cause localized sensations.

The galvanic skin response specifically relates to the skin's electrical activity in reaction to stimulation—this can affect the accuracy of any readings taken from such electrodes, since the resulting interference can create misleading data. Therefore, it's crucial to consider the materials used in electrode construction to mitigate such occurrences, ensuring accurate measurements during sleep studies or other assessments that leverage electrodermal activity.