Influence of electrode site and size on variability of magnetic evoked potentials.
Successive magnetic evoked potentials (MEPs) concern varying motor neurons. We investigated whether this MEP-specific source of variability depends on electrode site and size. Amplitude variability (standard deviation) was largest over the center of the hypothenar muscles. Latencies were longer at distal and proximal sites than at the center site. Large electrodes (10 cm2) did not decrease this source of amplitude variability compared with EEG electrodes, in contrast to other sources of variability.
Dunnewold
R J
RJ
Department of Neurology and Clinical Neurophysiology, Leiden University Hospital, The Netherlands.
van der Kamp
W
W
van den Brink
A M
AM
Stijl
M
M
van Dijk
J G
JG
D000328:Adult; D004566:Electrodes; D004867:Equipment Design; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006225:Hand; D006801:Humans; D008280:Magnetics / Q000295:instrumentation; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology