The N18 component of the median nerve SEP is not reduced by vibration.
OBJECTIVE
To study the interference of mechanical vibration of the palm of the hand on the median nerve short-latency SEP components.


METHODS
Electrically-elicited short-latency median nerve SEP were obtained before and during mechanical vibration (120 Hz) of the palm in two groups of normal individuals (6 in group I and 9 in group II). The amplitude of the different components was compared between the two conditions through non-parametric statistical tests.


RESULTS
A significant reduction in the amplitude of the N9, P13/14 and N20 components was detected, however no overall significant changes were detected for the N18 component.


CONCLUSIONS
Vibration interference reduced all studied components except the N18, these findings are interpreted as supporting evidence for the proposed association between the N18 component and the inhibitory activities elicited in the dorsal column nuclei.
Department of Neurology, Escola Paulista de Medicina, UNIFESP, São Paulo, SP, Brazil.
G M
GM
Manzano
N
N
Negrão
J A
JA
Nóbrega
D000328:Adult; D005073:Evoked Potentials, Somatosensory; D005260:Female; D006225:Hand / Q000294:innervation; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000502:physiology*; D008875:Middle Aged; D011930:Reaction Time / Q000502:physiology; D014732:Vibration