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Mental rotation is a spatial representation conversion capability using an imagined object and either object or self-rotation. This capability is impaired in schizophrenia.To provide a more detailed assessment of impaired cognitive functioning in schizophrenia by comparing the electrophysiological profiles of patients with schizophrenia and controls while completing a mental rotation task using both normally-oriented images and mirror images.This electroencephalographic study compared error rates, reaction times and the topographic map of event-related potentials in 32 participants with schizophrenia and 29 healthy controls during mental rotation tasks involving both normal images and mirror images.Among controls the mean error rate and the mean reaction time for normal images and mirror images were not significantly different but in the patient group the mean (sd) error rate was higher for mirror images than for normal images (42% [6%] vs. 32% [9%], t=2.64, p=0.031) and the mean reaction time was longer for mirror images than for normal images (587 [11] ms vs. 571 [18] ms, t=2.83, p=0.028). The amplitude of the P500 component at Pz (parietal area), Cz (central area), P3 (left parietal area) and P4 (right parietal area) were significantly lower in the patient group than in the control group for both normal images and mirror images. In both groups the P500 for both the normal and mirror images was significantly higher in the right parietal area (P4) compared with left parietal area (P3).The mental rotation abilities of patients with schizophrenia for both normally-oriented images and mirror images are impaired. Patients with schizophrenia show a diminished left cerebral contribution to the mental rotation task, a more rapid response time, and a differential response to normal images versus mirror images not seen in healthy controls. Specific topographic characteristics of the EEG during mental rotation tasks are potential biomarkers for schizophrenia.心理旋转(mental rotation)是一种想象客体或自我旋转的空间表征转换能力。精神分裂症患者的心理旋转能力受损。记录精神分裂症患者和健康对照者完成正像和镜像心理旋转任务时的脑电生理指标，比较这些指标的差异，深入评估精神分裂症患者的认知损害情况。对来自解放军第三医院精神科32例精神分裂症患者和29例健康对照者在完成正像和镜像的心理旋转任务时的事件相关电位测定，比较两组错误发生比例、反应时以及事件相关电位的脑地形图。对照组正像与镜像的错误率比较无明显差异，正像与镜像的反应时间亦无明显差异。而患者组镜像的平均（标准差）错误率比正像高 [42%（6%）比32%（9%），t=2.64，p=0.031]，患者组镜像的反应时比正像长 [587（11）ms比571（18）ms，t=2.83，p=0.028]。无论是镜像还是正像，患者组Pz（顶区）、Cz（中央区）、P3（左侧顶区）和P4（右侧顶区）的P500波幅均低于对照组。与P3极点相比，两组正像和镜像P4点波幅都偏高。精神分裂症患者正像和镜像心理旋转能力都受损。患者大脑左半球心理旋转能力减弱，反应时缩短，对正像与镜像反应存在差异，这些都与对照组不同。研究提示完成心理旋转任务时特定的脑地形图可作为诊断精神分裂症的一个辅助参考指标。