Directionally-sensitive peripheral nerve recording: bipolar nerve cuff design.

Although bipolar nerve cuff electrodes (NCEs) are used in clinical neurostimulation therapies (e.g., epilepsy, obstructive sleep apnea), the use of this electrode as part of a closed-up controlled system is very limited. The literature points to high noise content (i.e., poor signal-to-noise ratio, SNR) as the primary reason for not using bipolar NCEs to record neural activity. In fact, over the past several decades, the pseudo-tripolar NCEs, the symmetric configuration of this electrode array (i.e., electrically-shorted side contacts) makes it very difficult to obtain directional information from the recorded neural activity (efferent vs. afferent). In this study, we investigated the feasibility of using a bipolar NCE to achieve low-noise, directionally-sensitive recording of peripheral nerve activity.