A novel stimulus artifact removal technique for high-rate electrical stimulation.
Electrical stimulus artifact corrupting electrophysiological recordings often makes the subsequent analysis of the underlying neural response difficult. This is particularly evident when investigating short-latency neural activity in response to high-rate electrical stimulation. We developed and evaluated an off-line technique for the removal of stimulus artifact from electrophysiological recordings. Pulsatile electrical stimulation was presented at rates of up to 5000 pulses/s during extracellular recordings of guinea pig auditory nerve fibers. Stimulus artifact was removed by replacing the sample points at each stimulus artifact event with values interpolated along a straight line, computed from neighbouring sample points. This technique required only that artifact events be identifiable and that the artifact duration remained less than both the inter-stimulus interval and the time course of the action potential. We have demonstrated that this computationally efficient sample-and-interpolate technique removes the stimulus artifact with minimal distortion of the action potential waveform. We suggest that this technique may have potential applications in a range of electrophysiological recording systems.
Heffer
Leon F
LF
Department of Otolaryngology, The University of Melbourne, Melbourne, Australia. l.heffer@pgrad.unimelb.edu.au
Fallon
James B
JB
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D016477:Artifacts; D003056:Cochlear Nerve / Q000502:physiology; D003627:Data Interpretation, Statistical; D004558:Electric Stimulation / Q000379:methods*; D004594:Electrophysiology; D006168:Guinea Pigs; D008839:Microelectrodes; D009412:Nerve Fibers / Q000502:physiology