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Objective:To explore the effect of intermittent theta-burst stimulation (iTBS) of the cerebellum on the excitability of the M1 zone in the bilateral motor cortex and the duration of any effect.Methods:Twenty healthy youths were randomly assigned to a left or a right cerebellum iTBS group, each of 10. The resting motor threshold and motor evoked potential (MEP) of the motor cortex were determined before giving 600 pulses of iTBS. Then MEP was measured at the 5th, 10th, 15th, 20th, 25th, 30th, 35th and 40th minute after the intervention ended. Any changes in MEP amplitude were also analyzed.Results:①The average MEP amplitude in the right motor cortex had increased significantly in the left cerebellum iTBS group from the 5th to the 15th minute. The increase lasted at least 10 minutes. Then it had returned to the baseline value at the 35th minute. ②The MEP amplitude in the left motor cortex decreased slightly after iTBS of the left cerebellum began, but there were no significant changes. ③The MEP amplitude in the left motor cortex had a tendency to decrease after iTBS was administered to the right cerebellum, but that change too was not significant. ④The MEP amplitude of the right motor cortex decreased significantly only for the first 30 minutes.Conclusions:iTBS of the cerebellum can increase the excitability of the contralateral motor cortex. The effect can last 25 minutes. It can also decrease the excitability of the ipsilateral motor cortex for 30 minutes.
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Objective:To investigate any change in the effective connectivity between the bilateral anterior central gyruses after transcranial magnetic stimulation (TMS).Methods:Twenty-one healthy subjects were examined using resting state functional magnetic resonance imaging (rs-fMRI) before and after receiving continuous theta burst stimulation (cTBS). The brain atlas of the Institute of Automation of the Chinese Academy of Sciences was used for fine partitioning of the bilateral anterior central gyruses. Granger causality analysis was used to compare any changes in the effective connectivity between them.Results:After the cTBS inhibited the right M1 area, significant changes in effective connectivity among the sub-regions of the bilateral M1 area were observed. The effective connectivity of the right upper limb to the left upper limb and the left head to face were weakened, while that of the left upper limb to the right head, as well as of the face to the right upper limb was enhanced.Conclusion:For people whose right M1 area has been inhibited by cTBS, the effective connectivity changes in both upper limb functional areas of the M1 region reflect inter-hemispheric inhibition. Opposite changes were found in the trunk and upper limbs.
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Objective:To explore the effectiveness of evaluating voice disorders in dysarthria patients after brain injury using speech production measurements and analyze their phonics characteristics.Methods:Twenty-nine patients were divided into a severe dysarthria group ( n=19) and a mild dysarthria group ( n=10) through the subjective evaluation of their speech, and then evaluated using a computer speech monitor. The maximum phonation time (MPT), maximum counting ability (MCA), basic frequency (F0), standard deviation of F0 (F0SD), F0 range, intensity, formant, and the distance of jaw and tongue movements were recorded. Results:All of the patients displayed abnormal MPTs and MCAs, with the average MPT and MCA of the severe dysarthria group significantly lower than the mild group′s averages. In the severe dysarthria group, the abnormal F0s, F0SDs, F2(i)s and tongue movement distances were significantly greater than in the mild group.Conclusions:Speech production measurements can be applied to evaluate the speech dysarthria patients after brain injury. It is very common for such patients to have impaired speech and respiratory function, so this is worthy of attention.
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Objective To study the effects of active and passive movement of the affected hand after ischemic stroke on brain activity patterns using blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-fMRI) and to explore the central mechanism of movement treatment for hand disability.Methods Five pa-tients with subcortical cerebral infarction in Brunnstrom stages 1 to 3 (both upper limb and hand affected) were investigated using BOLD-fMRI during active and passive clenching and relaxing of the affected hand.Statistical parametric mapping software (SPM5) was used to integrate the activity data and display them in one standard brain map.The activated areas were then compared.Results The BOLD-fMRI signals aroused by both active and passive move-ment were enhanced in the contralateral sensorimotor cortex,the contralateral premotor cortex,bilaterally in the sup-plementary motor area and in the bilateral cerebellum.Both movements also activated the ipsilateral sensorimotor cor-tex and premotor cortex,which are not normally activated during such movements in healthy people.The areas were more extensive and the activation was stronger during passive movement.Moreover,the activated brain areas induced by active movement were mainly on the contralateral side,while passive movement induced activation distributed over both hemispheres almost evenly.Conclusions Both active and passive movement significantly activate the brain areas responsible for movement of the affected hand.Both are useful for boosting brain reorganization after stroke.
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Objective To assess differences in brain activation between active and passive movement of the right hand using blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI). Methods Nine healthy adult right handed volunteers were studied. fMRI was performed with active and passive finger-to-finger movement. Results Right hand active and passive movement produced significant activation in the contralateral sensorimotor cortex ( SMC ), the contralateral premotor cortex ( PMC ), bilaterally in the supplementary motor area (SMA) and in the ipsilateral cerebellum. The activated brain areas were centered on the contralateral SMC and PMC and located more forward during active movement than during passive movement. The contralateral SMC was the most strongly and the most frequently activated brain area. The contralateral posterior parietal cortex (PPC) was less relevant to the hand movements. Unlike active movement, passivemovement activated more areas in the posterior central gyrus than in the anterior central gyrus. Conclusions Both active and passive movement significantly activate the brain areas which are responsible for hand movement, but there are some differences in the locations of the cortex areas activated and in the incidence activation except in the contralateral SMC.
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Objective To investigate the underlying mechanism of motor recovery of the hemiplegic lower extremity in stroke patients. Methods The brain activation pattern during sequential extension-flexion of the affect-ed knee of 7 stroke patients and 8 healthy subjects was observed by blood-oxygen- level-dependent fMRI (BOLD-fM-RI) and analyzed by microsoft SPM5. Results When executing unilateral knee flexion-extension, contralateral paracentral lobe and contralateral supplementary motor area and right temporal gyms and inferior parietal lobes of both sides were significantly activated in all the healthy subjects, while the ipsilateral parietal lobe BA7 and BA5 were sig-nificantly activated in 6 of the 7 stroke patients. Conclusions Sequential extension-flexion of the affected knee of stroke patients was probably dependent on the activation of BA7 and BA5 in the intact side. Compensatory activation of the intact hemisphere might be one of the main mechanisms for the paretic lower extremity motor recovery in stroke patients.