정신분열증 환자에서 시각유발전위 P100의 지표학적 뇌영상

Topographic Brain Mapping of Visual Evoked Potential P100 in Schizophrenia

PI00 is one of the most stable and consistent visual evoked potentials. This is closely linked with visual information processing which has been thought to be generated in the cortical area (calcarine area). It has been extensively evaluated in psychiatric reseach, and many investigators have been trying to seek the relation between visual information processing and psychopathology, and it’ s clinical significance. It is now possible to map the spatiotemporal evaluation and statistical results of VEP PI00 wave form using the topographic brain mapping system developed by computer graphics and electronic engineering. Recently, the topographic brain m apping of VEP PI00 has been applied to evaluate the disturbance of visual information process, particularly with regard to the topographic distribution of P100 in schizophrenics. However, the results have been inconsistent With these aspects in mind, this study was designed to evaluate not only the amplitude but also the topographic distribution of VEP P100 in schizophrenics, and to examine the availability of the characteristic findings of VEP PI00 mapping as one of the biological markers. The subjects were consisted of 40 Schizophrenics who had been admitted to Our Lady of Mercy Hospital and Catholic University Medical College from September, 1989 to A ugust 1992. They did not take any psychotrophic medications for more than 4 weeks. 42 normal controls also did not take any psychotrophic medications for more than 4 weeks. The results were as follows : 1) In schizophrenics the latency of V EP P100 was 102msec. Positive and negative m ax im um amplitudes of P100 was 4.65士 3.44|iV in O 2 and ᅳ 2.4 8士 2.02|iV in F 3, respectively. The amplitude of P100 showed negativity in frontal area and positivity in occiptial area, and showed symmetrical topographic distribution. 2) In normal controls, the latency of V E P P100 was 104msec. Positive and negative m ax im um amplitudes of P100 was 3.95± 2.42|iV in O 2 , and ᅳ 2.55± 2.03|iV in F 3 , repectively. The amplitude of P100 showed negativity in frontal area and positivity in occipital area showed symmetrical topographic distibution. 3) At th latency point VEP PI00 showed no differences of amplitude in entire cortex, and showed no differences of topographic distribution between the groups. 4) Spatiotemporal analysis of VEP PI00 showed similiar beginning and ending point in time, and showed simliar topographic distribution during entire PI00 process in both groups. In light of our findings, it seems likely that the visual information processing shown in schzophrenics’ optic pathway, visual cortex and other association area is not different from that shown in normal control