Assessments of cognitive function of schizophrenic patients using fMRI, ERP and LORETA

功能性MRI、ERP、LORETA等可以相互补充时间和空间分辨率。功能MRI与LORETA相结合是评估精神分裂症患者信息加工的一种有效方法。我们专注于两个主要系统；视觉处理系统和工作记忆系统。视觉感官输入在枕叶区通过自上而下和自下而上过程的前馈和反馈相互作用进行处理。刺激和反应之间的映射可以在前额皮质的工作记忆系统中进行管理。实验任务及总结结果如下：工作记忆系统听觉怪异范式；被动听觉新颖性辨别的前颞叶功能障碍。反应竞赛；枕颞区视觉处理系统面部、眼睛、眼动识别；枕叶皮层、脑岛皮层和枕叶外皮层的面部加工活动不足；杏仁核、脑岛和枕叶外皮层的眼睛和动眼加工活动过度。错觉轮廓感；外皮层的IC加工不活跃，ACC和脑岛的IC加工过度活跃。全局-局部感知；精神分裂症患者的左半球过度活跃，右半球过度活跃，右半球过度活跃。颅外皮层在加工过程中缺乏知觉整合，这可能会增加前额叶皮层在高级加工过程中所需的负荷。此外，患者的半球功能性偏侧可能与健康对照者不同。

Functional MRI, ERP, LORETA and can complement the time and spatial resolution of each other. The combination of functional MRI and LORETA is a strong method to evaluate information processing in schizophrenia. We focused on the two main systems ; visual processing system and working memory system. Visual sensory inputs are processed in occipitemporal regions through feedforwad and feedback interactions between top-down and bottom-up process. And then mapping between stimulus and responses can be governed in the working memory system in prefrontal cortex. Experimental tasks and summaries results of are as follows :Working memory systemAuditory oddball paradigm ; front-temporal dysfunction in passive auditory novelty discrimination.Response competition ; deteriorated central executive systemVisual Processing System in Occipitemporal RegionsFace, eyes, eye-movement recognition ; underactive in face processing in occipitemporal cortex, extrastriatelOveractive for eyes and moving-eyes in the amygdale, insula, and extrastriate cortex.Illusory contour perception ; Underactive in IC processing in extrastriate, overactive for IC in ACC and insula.Global-Local perception ; underactive in Global processing in right occipitemporal cortex, overactive in Local processing in left occipitemporal cortex and PFC. Left hemisphere overactive-right hemisphere underactive in schizophrenic patients.Deficient in perceptual integration during processing in the extrastriate cortex, which might consequently increase the loads needed in the higher processing in the prefrontal cortex. Furthermore, the patients might have different profiles of hemispheric functional laterality from healthy control subjects.