Abstract:
‘Common Electrode’ microneurography (i.e. stimulating a nerve and recording return afferent neural activity through the same microelectrode
facilitates investigation of linkages between sensory and motor nervous systems in humans. Currently there is no commercial product designed
specifically to conduct common electrode microneurography experiments. However, such experiments would advance investigations in several key
areas including spinal injury research.
In this paper, we report on the successful production and testing (on a human subject) of an integrated amplifier built specifically for this purpose.
The amplifier was built using commercially available components to allow for both easy and economical manufacture. In particular, we report on
the design requirements and outline our chosen design solutions.
The amplifier handles low-level neural signals amidst large 50 Hz interference, with protection against potentially high stimulation voltages of
over 100V dc, with minimal cross-coupling of rapid stimulus pulses onto the high gain amplifier’s input, and a short ‘blocking’ time between
stimulation and recording. The amplifier also includes necessary filters, selectable gains and internal stimulator triggering circuits to provide a
simple, integrated solution for common electrode operation on human subjects.
