| Objective:To observe the active areas in the brain by simple motor task (repetitive and sequential finger-to-thumb opposition movements in turn),voluntary motor task (grasping object) and imagined motor task and study the mechanism of the brain regions activated in order to provide the evidence of motor recovery after stroke and injury of skull and brain. That have important significance for the direction of clinical rehabilitation treatment of central nervous system paralysis. Material and Methods Twelve normal subjects (including men 6, women 6) with 8 right dominant hand and 4 left dominant hand were selected, age ranged from 18 to 45(mean 29.33±9.60) year old. All had negative results of brain MRI. Functional magnetic resonance imaging was perfomed at 1.5 T GE MR/i HiSpeed with Gradient Echo and Echo Planar sequence, a TR of 2000 ms, and TE 60 ms, flip angle 90o, matrix 128×192, field of view 24 cm, scan time 4:16, and an images acquired in a layer per 2 second, in total 512 images in 4 layer. Motor tasks were simple motor task (repetitive and sequential finger-to-thumb opposition movements in turn),voluntary motor task (grasping object) and imagined motor task. Axial and coronal images were obtained durings each motor task, in all 6 times scan, total 30 minutes. Sagittal imaging T1W (500/50/1) was performed firstly and definite unremarkable, then we divided into 4 layer from the top of corpus callosum to the inner skull in sagittal position, slice thickness 6 mm, slice interval 2 mm. The coronal images was obstained at the same way, parallel to brainstem from the frontier of brainstem to start (including larger partial cerebellum), slice thickness 10 mm, slice interval 3 mm. The axial and coronal images will take as reference of functional images. Motor tasks were performed by all subjects in the wakefulness, who did some exercise about simple motor task and imagined motor task in advance, the content of voluntary motor task was unknown to all subjects. The first 16 seconds is to acquire compensative images, then the rest period, motor task performed by right hand and left hand for 20 seconds repectively in turn. The rest state, right hand action and left hand action conformed a cycle, and four cycle continuously. The operator pated the subject's hand wich will move for the beginning. We apply SUN, GE Advanced Workstation3.1 of Function1.9 to after-finishing and analyse the images. Reject the first 16 second compensative images, then caculate to get positive correlation coefficient. Detect the correlation coefficient of region of intrest, which of the active areas were larger than 0.5 or equal to 0.5.The reconstruct way of active areas by right hand is to reject the first 16 second compensive images, then take the images in the rest state for comparative parameter and the 20sec images of right hand action for the positive correlation coefficient of active areas by right hand, the following 20sec images of left hand action and the rest state for comparative parameter of right hand. On the contrary, the images of the right hand action and the rest state were taken as the comparative parameter for that of the left hand action, and that of left hand action for positive correlation coefficient. We added the acquired functional images to corresponding T1 dissection diagram in the axial or coronal position and count the number of active areas. The statistic were carried out with the SPSS's Fisher's exact test. Results:According to the correlation coefficient that defined, we conducted functional images of brain with special software. Besides ipsilateral imagined motor task having no activation in 2 subjects, we obstained satisfied images activated by three motor tasks in all subjects. During simple and complex motor tasks with dominant and nodominant hand, contralateral anterior and posterior central gyrus, correspond to primary sensorimotor areas, not only were activated in cluster,but also had more active cluster areas, but ipsilateral SM1 was activated partially with nodo...
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