The study of pathophysiological mechanism for the subcortical dementia- an evaluation using event-related potentials tomography

为探讨皮层下痴呆的病理生理改变，对皮层下痴呆的事件相关电位进行了分析。作为基础研究，我们考察了任务相关性和听觉P3a成分的新奇的影响。我们的研究结果表明，新奇P300的表征可能依赖于平行加工过程中用于新颖刺激的心理资源。在基础研究之后，我们采用听觉oddball范式和4音范式评价了血管性痴呆（VaD）患者的信息加工障碍特征。提示轻度VaD患者的心理功能障碍不仅表现为信息加工速度的异常，还表现为心理资源分配的异常。第三部分是帕金森病皮层下痴呆的病理生理机制的评价。采用事件相关电位地形图检测帕金森病患者的心理转换功能障碍。我们的研究结果表明，减少心理转换的原因缺乏新奇的P3习惯化的PDP，这是与学习障碍的基础上的额叶和基底ganglia.Finally，我们调查是否会阻碍早期信息加工的听觉感觉输入的PDP。实验结果表明，PDP对听觉感觉输入的信息加工存在自动加工和控制加工功能障碍。

To evaluate the pathophysiological changes in subcortical dementia, electrical filed of the event-related potentials were analyzed. As the fundamental study, we examined the effect of task relevance and the novelty of P3a components in an auditory study. Our data suggest that the characterization of novelty P300 may depend on the mental resources that can be devoted to novel stimuli during parallel processing.After the fundamental study, we evaluated the characteristics of information processing disturbance in patients with vascular dementia (VaD) using auditory oddball and 4-tone paradigms. The data suggest that the characteristics of mental dysfunction in mild VaD patients do not only depend on abnormal information processing speed but also abnormal mental resource allocation.The 3rd study is the evaluation of pathophysiological mechanism for the Parkinson's disease as subcortical dementia. Event-related potentials topography produced by novel and target stimuli was used to detect dysfunction of mental switching (perseveration) in Parkinson's disease Parkinson's disease patients (PDPs). Our findings suggest that decreased mental switching causes lack of novelty P3 habituation in PDPs and that this is related to learning disability based on dysfunction of frontal lobe and basal ganglia.Finally, we investigated whether early information processing for auditory sensory input would be hindered in PDPs. The data indicated that there are dysfunction both of automatic and controlled processing in the information processing for auditory sensory input in the PDP.