图形视诱发电位半球分布变异的研究

研究16例正常人PVEP半球分布的变异发现:3例头部二侧全视野反应对称的P100振幅下降至正常范围(2.5μV),但同侧和对侧半视野反应振幅相似而极性相反;12例全视野非对称P100振幅大于2:1,可由于半视野对侧成分的减小或抵销所致;5例半视野正常P100潜伏期和全视野延迟P100潜伏期与在P100和N105总合后出现的较大振幅P135被P100代替有关,1例全视野双侧反应的P100反向极性可由于N105振幅较P100的为大所引起。

Study on the Variability of Hemisphere Distribution of Pattern Visual Evoked Potentials

The 16 normal subjects with the variability of the hemisphere distribution of PVEP were studied. The results showed as follows: (1) The symmetrical P100 amplitudes lowed down to normal limits(2.5uv) in full-field responses at bilateral scalp were seen in three cases, while the ipsilateral and contralateral components in half-field responses were of similar amplitude and opposite polarity; (2) The asymmetrical P100 amplitudes over 2:1 in full-field responses in 12 cases could be attributed to the reduction or cancellation of the contralateral components recorded from each visual half-field; (3) Delayed P100 latency in full-fleld responses and normal P100 latency in half-field responses ins cases could be associated with larger amplitude P135 (PNP waves) which replaced with P100 (NPN waves) after summation of P100 and N105; (4) The opposite polarity of P100 in full-field responses at bilateral scalp in one case might be caused by N105 amplitude larger than that of P100.