Possible role of the basal ganglia in the generation of the N30 potential of the median nerve somatosensory evoked potentials.
OBJECTIVE
The origin and afferentation of the frontal N30 component of the median nerve somatosensory evoked potentials (SEPs) have not yet been fully elucidated. The aim of this study was to assess the possible selective impairment of the N30 component in patients with lacunar infarcts of the basal ganglia as compared to patients with lacunar infarctions sparing the basal ganglia and to a group of healthy subjects.


METHODS
Median nerve SEPs were measured in ten patients with lacunar infarctions of the brain (but no cortical atrophy or leukoaraiosis) and 13 healthy volunteers. Four patients had lacunar infarctions affecting the basal ganglia and 6 patients had lesions affecting other structures.


RESULTS
In two patients with lesions affecting the head of the caudate nucleus, there was no identifiable N30 component on the affected side. In one patient with bilateral lesions of the globus pallidus, the amplitude of the N30 component was significantly reduced. In one patient with lesion of the tail of the caudate nucleus, the N30 component was unaffected. The amplitude of the N30 component was also reduced in two patients with frontal subcortical white matter lesions. In all the other subjects, we recorded normal N30 components on both sides.


CONCLUSIONS
Our results further support the importance of the basal ganglia, especially the head of the caudate nucleus in the generation of the N30 component of the median nerve SEPs.
Beniczky
Sándor
S
Department of Neurology, Faculty of Medicine, University of Szeged, Szeged, Hungary. besa@nepsy.szote.u-szeged.hu
Nagy
Helga
H
Varga
Edina
E
Vörös
Erika
E
Kéri
Szabolcs
S
Vécsei
László
L
D000328:Adult; D001479:Basal Ganglia / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002544:Cerebral Infarction / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005073:Evoked Potentials, Somatosensory; D006801:Humans; D008279:Magnetic Resonance Imaging; D008475:Median Nerve / Q000503:physiopathology*; D008875:Middle Aged; D014057:Tomography, X-Ray Computed