peared. CT showed hemorrhagecaused by luxury perfusion inthe leftparietallobe. The. Iesionwas mainly inthe area posterierto the postcentralsulcus, probably.
The UOEHAssociation The UOEH Association
J UOEH
of ofHealth Health Sciences Sciences
(2004)
26(3):267-285
267
(Original]
Effect of Different Stimulus Frequencies on Short-latency Somatosensory Evoked Potentials in Patients with Focal Brain Lesions Tetsuya GENNMoTo,
Akira YoKoTA Department ofNeurosurgery,Schoot ofMedicine,Uhiversity and EnvironmentalHkalth, qf Occupationat Japan.
EiichirouURAsAKI
and
Ydhatanishi-ku, Kitakyushu 807-8555, Japan
investigate whether
the abnorrnality of short-latency somatosensory evoked with focal brain lesions is enhanced by different potentials(SSEPs)in patients stimulus frequencies, the median nerve at the wrist in 10 normal subjects and 12 central and parietal)lesions was stimulated electripatientswith cortical(frontal, cally at 1.3-18.3 Hz. Normal subjects had decreased frontal P22-N30 and parietal P27 amplitudes at high:Volume
conduction
of
T, Suenaga T, ShigematuK, Iwami O &
the parietal N20 potential to the prerolandic frontal area.
Brain 113: 1501-l509 27. Connemann BJ, KoehlerJ,PresserS & HopfHC
Latencyand (1999):
amplitude
in serial
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ClinNeurophysiol110: 1664-1668 28. Mauguiere E AttisonT, BabiloniC et at (1999):Somatosensory evoked potentials.The internamediannerveSEPrecordings.
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focalbrainlesionsremote
(1980):Somatosensory eyoked potentials:Abnormalities
from the primary sensorimotor
area.
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physiol 49: 59-65 30. FajiiM, Yamada T, AiharaM, Kokubun Y, Noguchi Y, Matsubara& Yeh MH stimulus rates upon
median,
ulnar and radial nerve
somatosensory
evoked
: The (1994)
effect of
potentials.Electoroenceph
ClinNeurophysiol 92: 518-526 31. Valeriani M, Restuccia D, Di Lazzaro V, Le Pera D, Barba C, TonaliP & Mauguiere F (1998) : Dipolar sources of the early scalp somatosensory
ExpBrainRes
creasingstimulusrates,
to upper limb stimulation; potentials 120: 306-315 evoked
effect of
in-
32. TsukaharaN(1981): Synapticplasticityinthemammaliancentralnervoussystem. AnnRevNeurosci
4: 351-379
33. Brunel N & Wang XJ
