University Hospital of Psychiatry Zurich, Department of Psychiatry, Psychotherapy and Psychosomatics, Militärstr. 8 / PO 1930, CH 8021 Zurich, Switzerland.
University Hospital of Psychiatry Zurich, Department of Psychiatry, Psychotherapy and Psychosomatics, Militärstr. 8 / PO 1930, CH 8021 Zurich, Switzerland.
Psychiatry Res. 2014 Mar 30;215(3):533-9. doi: 10.1016/j.psychres.2013.12.025. Epub 2013 Dec 21.
The N400, an event-related brain potential (ERP), can be triggered by semantic or arithmetic violations in visual or auditory stimulus material. Schizophrenia patients exhibit an altered N400 presumably resulting from impaired semantic memory associative networks. The present study investigates, whether an altered N400 can also be found in semantic violations of the own self-concept. We use simple descriptive sentences to combine semantics with the self-concept in order to explore differences and possible deficits in schizophrenia patients. Schizophrenia patients and controls were shown trait adjectives in reference to themselves. Participants had to decide if the presented trait adjective was congruent or incongruent with their own self-concept. Only in controls, the N400 was significantly more negative in the incongruent compared to the congruent condition. Controls seemed to profit from a stable self-concept as they were faster in judging if a given trait was descriptive for the self than for someone else, which might result from processes related to the self-reference effect. Interestingly, in schizophrenia patients, the higher the scores for ego pathology were, the smaller the N400 effect turned out to be. The diminished N400 effect is probably associated with a disturbed self-concept in schizophrenia.
N400 是一种事件相关的脑电位（ERP），可以通过视觉或听觉刺激材料中的语义或算术违规来触发。精神分裂症患者表现出的 N400 改变可能是由于语义记忆联想网络受损所致。本研究探讨了在自我概念的语义违规中是否也能发现 N400 的改变。我们使用简单的描述性句子将语义与自我概念结合起来，以探索精神分裂症患者的差异和可能存在的缺陷。给精神分裂症患者和对照组展示了与他们自己有关的特质形容词。参与者必须判断所呈现的特质形容词与自己的自我概念是一致还是不一致。只有在对照组中，不一致条件下的 N400 明显比一致条件下的 N400 更负。对照组似乎从稳定的自我概念中获益，因为他们在判断一个特定的特质是否描述自己时比描述他人时更快，这可能是由于与自我参照效应相关的过程所致。有趣的是，在精神分裂症患者中，自我病理学评分越高，N400 效应越小。N400 效应的减弱可能与精神分裂症患者自我概念的紊乱有关。
