Velocity-selective recording from frog nerve using a multi-contact cuff electrode.

Obtaining neural information from nerve cuff recordings for use as feedback signals for neural prostheses is slowly becoming state-of-the-art. Traditional tripolar cuff recordings cannot provide information on the fiber type contributing to the compound electro neurogram. In order to get this data we employed a novel nerve cuff carrying eleven electrode contacts equally distributed along its axis. Connecting this cuff to a custom made low-noise ten-channel amplifier, a data acquisition system and applying some basic data processing routines, we were able to generate profiles that show, for the first time, the different propagation velocities that contribute to the whole nerve signal.