Alternate excitation of large and small axons with different stimulation waveforms: an application to muscle activation.

A method has been developed to activate separately and alternately two axon groups in an intact nerve trunk through a single-channel stimulation electrode. Two types of stimuli, quasitrapezoidal-shaped and narrow rectangular-shaped current pulses, were employed to activate smaller and larger axons, respectively. The technique was demonstrated on an alpha motor fibre population in cat peripheral nerve and was utilised to reduce muscle fatigue during repetitive stimulation. This method may have applications in physiological research and the design of neural prostheses.