A low-noise gaited amplifier for closed-loop controlled fes systems

A low-noise battery powered high gain gaited preamplifier was developed for recording of afferent nerve activity in peripheral nerves. This low power device was tested in chronic experiments using a triphasic cuff electrode for neural recording at the tibial nerve of the cat. Recording in presence of stimulation has been tried in a closed-loop control: the lateral gastrocnemius was stimulated while the processed tibial nerve recordings were above an arbitrary selected threshold. We found that recordings showed reasonable rejection of stimulation and M-wave artifacts, while retaining the information of interest.