Kiang Michael, Kutas Marta
Department of Cognitive Science, University of California-San Diego, 9500 Gilman Dr., Mail Code 0515, La Jolla, CA 92093-0515, USA.
Schizophr Res. 2005 Sep 15;77(2-3):329-42. doi: 10.1016/j.schres.2005.03.021.
Disorganized speech in both schizophrenia and schizotypy has been hypothesized to result from abnormalities in how concepts activate one another in semantic memory. To study whether schizotypy is associated with differences in how categories activate their exemplars, we examined the N400 component of the event-related brain potential (ERP) elicited during a category-verification task. ERPs were recorded in young adults from the general population while they viewed category definitions each followed by a target that was either a high-typicality exemplar, low-typicality exemplar, or non-exemplar; participants' task was to indicate whether or not the target belonged to the category. Schizotypy was assessed via the Schizotypal Personality Questionnaire (SPQ). Overall, N400 amplitude was largest for non-exemplars, smallest for high-typicality exemplars, and intermediate for low-typicality exemplars. SPQ score was associated with decreased N400 amplitude to non-exemplars, and increased amplitude to both types of exemplars. SPQ score was negatively correlated with the N400 amplitude difference between non-exemplars and both low- and high-typicality exemplars, but was not correlated with the amplitude difference between low- and high-typicality exemplars. N400 amplitude differences between non-exemplars and both types of exemplars were correlated with the SPQ Interpersonal factor, but not the Disorganized factor. The results are consistent with an association of schizotypy with decreased use of context to activate related items and inhibit unrelated items.
精神分裂症和分裂型人格障碍中的言语紊乱现象，据推测是由于语义记忆中概念相互激活方式的异常所致。为了研究分裂型人格障碍是否与类别激活其范例的方式差异有关，我们在一项类别验证任务中检查了事件相关脑电位（ERP）的N400成分。在普通人群的年轻成年人观看类别定义后紧接着出现的目标时记录ERP，目标分别为高典型性范例、低典型性范例或非范例；参与者的任务是指出目标是否属于该类别。通过分裂型人格问卷（SPQ）评估分裂型人格障碍。总体而言，N400波幅在非范例中最大，在高典型性范例中最小，在低典型性范例中处于中间水平。SPQ得分与对非范例的N400波幅降低以及对两种范例的波幅增加有关。SPQ得分与非范例和低、高典型性范例之间的N400波幅差异呈负相关，但与低典型性范例和高典型性范例之间的波幅差异无关。非范例与两种范例之间的N400波幅差异与SPQ人际因子相关，但与紊乱因子无关。结果表明分裂型人格障碍与减少利用上下文激活相关项目并抑制无关项目有关。
