Bobes M A, Lei Z X, Ibáñez S, Yi H, Valdes-Sosa M
Cuban Center for Neuroscience, Havana, Cuba.
Biol Psychiatry. 1996 Aug 1;40(3):189-202. doi: 10.1016/0006-3223(95)00352-5.
In this study the N400 of schizophrenics was compared with that of control subjects in a picture semantic-matching task. The comparison of N400 difference waveforms (subtraction of event-related potentials of congruent from those of incongruent trials) between control and patients was supplemented by separate analysis for congruent and incongruent trials. The N400 latency was delayed in patients. Also, the amplitude of N400 in the difference waveform was reduced in schizophrenics; however only congruent trials were different for patients (more negative) with respect to controls. This result is consistent with the hypothesis that schizophrenics use context poorly, but inconsistent with simple versions of the idea that associations are generally disinhibited in schizophrenia. Since the amplitudes of N400 and an auditory P300 were not correlated, a general processing deficit does not explain the results. Finally, by using picture matching, a cross-cultural comparison of N400 in schizophrenics from Cuba and China was possible, which indicated that the N400 abnormalities were similar in both groups.
在本研究中，我们在图片语义匹配任务中，将精神分裂症患者的N400与对照组受试者的N400进行了比较。通过对匹配和不匹配试验的事件相关电位分别进行分析，补充了对照组与患者之间N400差异波形（从不匹配试验的事件相关电位中减去匹配试验的事件相关电位）的比较。患者的N400潜伏期延迟。此外，精神分裂症患者差异波形中N400的波幅降低；然而，仅在匹配试验中，患者（更负向）与对照组存在差异。该结果与精神分裂症患者对语境利用不佳的假设一致，但与精神分裂症中联想通常不受抑制这一观点的简单版本不一致。由于N400和听觉P300的波幅不相关，一般的加工缺陷无法解释这些结果。最后，通过使用图片匹配，对来自古巴和中国的精神分裂症患者的N400进行跨文化比较成为可能，这表明两组患者的N400异常情况相似。
