THE THEORY OF PERIPHERAL NERVE RECORDING

The main focus of this chapter is the bioelectrical, chemical, and physical theories underlying the recording of bioelectric potentials from the body, with emphasis placed on recording from the peripheral nervous system. Following a general overview of recording bioelectric signals, we start our discussion with a mathematical description of the extracellular electric field distribution produced by the active nerve fiber, and discuss implications from the model predicting how the electrode, its placement and recording configuration influences the recording. These models are based upon certain assumptions about the regular electrochemical properties of the system. We continue with a discussion of the properties of the electrolytic medium in which signals travel and make our way to the electrochemical interface in which they are picked up. Finally, we discuss the recording system that picks up the signal and methods to evaluate the quality of the signal and noise that exist in the recording.