Short latency somatosensory evoked potentials following mechanical taps to the face. Scalp recordings with a non-cephalic reference.
Trigeminal somatosensory evoked potentials were recorded over the scalp using non-cephalic reference sites following mechanical taps to the face. A negative wave form, Nf17, was recorded bilaterally with its highest amplitude over the frontal scalp contralateral to the side of stimulation. A localized negative wave form, Np25, was recorded over the centro-parietal scalp contralateral to the side of stimulation. Np25 had an onset latency of 16.46 msec. The location and restricted spatial distribution of Np25 suggest that it represents the initial activation of the face area of the primary sensory cortex. The widespread bilateral nature of Nf17 and its latency of onset preceding that of Np25 suggest that Nf17 may be a 'far-field' potential reflecting activity in subcortical sensory pathways subserving the face.
Seyal
M
M
Department of Neurology, University of California, Davis Medical Center, Sacramento 95817.
Browne
J K
JK
D000328:Adult; D001921:Brain / Q000502:physiology; D001931:Brain Mapping; D004569:Electroencephalography; D005073:Evoked Potentials, Somatosensory; D005145:Face / Q000294:innervation / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010812:Physical Stimulation; D014276:Trigeminal Nerve / Q000502:physiology