A STUDY ON THE TEMPORAL CORRELATIONS OF THE FUNCTIONAL BRAIN AREAS USING FUNCTIONAL MRI

采用GE Horizon 1.5T临床MRI机进行功能磁共振成像（fMRI）实验.图像采集采用全脑图像和选择平面图像两种方法。主要采用统计参数映射（SPM）方法进行统计图像分析，在手指反向运动任务下，初级运动区和运动前区被激活。在两个脑区之间观察到相位偏移，表明两个脑区之间存在时间依赖的相位延迟（相关）。另一方面，在口吃受试者的经典语言区周围没有观察到激活。相反，观察到对侧的前扣带回激活。根据双眼视差的随机点立体图，V2、V3、V5、IPS、STS和Broca区被显著激活，表明M-通路主要参与了前扣带回的功能。为了分析任务间干扰，提出了频率标记多任务（FLMT）方法。布罗卡区不干扰其他任务，但不激活单眼立体视，这表明该地区肯定是参与距离评价从双眼视差。然而，我们没有观察到激活区域之间的任何相移，这表明立体视觉在人脑中的处理相当迅速。MTC-EPI方法已成功地应用于手指对置任务。MTC-EPI比仅使用BOLD效应的普通EPI对脑激活更敏感。另一方面，MTC-EPI对立体视觉的敏感性不高。MTC-EPI可能有利于局部激活。然而，要得出这一结论，还需要进一步调查。

Using a clinical MRI machine (GE Horizon 1.5 T), we conducted the functional magnetic resonance imaging (fMRI) experiments. Two kinds of methods were employed for the image acquisition, i.e. the whole brain image and the selected plane image. Statistical parametric mapping (SPM) method was mainly employed for the statistical image analysis.Primary motor area and pre-motor area were activated under the finger opposition tasks. Phase shift was observed between two regions, suggesting the time-dependent phase delay (correlation) between two regions.Broca's and frontal association area were activated during the word generation task. On the other hand, no activation was observed around the classical language area for the stuttering subjects. Instead, the activation of the anterior cingulate gyrus in the opposite side was observed. This is quite curious in light of the function of the anterior cingulate.V2, V3, V5, IPS, STS and Broca's area were significantly activated by the stereopsis of the random dot stereogram based on the binocular disparity, indicating that the M-pathway is mainly involved. Frequency labeled multiple task (FLMT) method has been developed in order to analyze the inter-task interference. Broca's area did not interfere with other tasks, but not activated during monocular stereopsis, suggesting that this region is definitely involved in the distance evaluation from the binocular disparity. However, we could not observe any phase shift between the activated areas, suggesting that the stereopsis is processed in the human brain quite rapidly.MTC-EPI method has been successfully applied to the finger opposition task. MTC-EPI was more sensitive to the brain activation compared to ordinary EPI using only the BOLD effect. On the other hand, MTC-EPI is not much sensitive for stereopsis so far. MTC-EPI may be advantageous for the localized activation. However, to conclude this, further investigation would be required.