慢性精神分裂症患者自我意识的功能性脑成像研究

目的探讨慢性精神分裂症患者及健康人自我意识加工的中枢机制及其异同。方法使用磁共振功能成像技术,观察20例慢性精神分裂症患者(患者组)和10名年龄、教育程度与患者组相匹配的正常人(对照组)在进行自我意识加工时,大脑激活区域的位置、范围和强度。结果对照组在进行自我意识加工时前额叶中央皮层和扣带回后部皮层显著被激活,激活范围分别为138和43个相连像素;患者组上述脑区的激活程度显著减低或消失,激活范围分别为9和0个相连像素。两组间的差别具有统计学意义(P<001)。结论前额叶中央皮层和扣带回后部皮层很可能是自我意识加工的功能脑区。慢性精神分裂症患者该脑区功能低下,是其自我意识障碍的影像学证据。

"Self"in schizophrenia:a functional magnetic resonance imaging study

Objective To assess the brain functional areas and states for self-referential processing in healthy person and chronic schizophrenia.Methods Block-designed blood oxygenation level dependent functional MRI was performed on 20 chronic schizophrenic inpatients and 10 matched healthy controls. The subjects were asked to making judgments for personality trait adjectives visually presented on the screen. They should answer if the adjective suitably describing them self (self-relevance), or other (other-relevance), or the word is negative or positive (semantic judgment). The brain activation map was obtained by using SPM99 software. The activation size, intensity, and location of 2 groups were compared.Results~During self-referential processing, the medial prefrontal cortex (MPFC) and posterior cingulated gyrus (PC) were strongly activated (activation cluster was 138 for MPFC and 43 for PC) in normal subjects,without great individual difference. While in schizophrenia the activation size was significantly reduced (activation cluster was 9 for MPFC and 0 for PC) with dramatic individual variety. The difference in activation size and intensity between 2 groups was significant (P<0.01).Conclusion MPFC and PC may be the functional areas for self-referential processing in healthy persons. The absent and/or reduced activation in schizophrenic patients reflects dysfunction in these areas, and thus provides a neurobiological imaging evidence for known impaired self-awareness in schizophrenia.