Study of paroxysmal kinesigenic dyskinesia with fMRI / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To detect the differences in subcortical structures between patients with paroxysmal kinesigenic dyskinesia (PKD) and normal subjects during movement preparation and execution.</p><p><b>METHODS</b>The PKD patients performed a movement task, in which a CUE signal (preparation) indicated the movement sequence prior to the appearance of an imperative GO signal (execution). Event-related functional magnetic resonance imaging (fMRI) and 3dDeconvolve program of AFNI were used to estimate the hemodynamic response function and to generate activation maps.</p><p><b>RESULT</b>During movement preparation, the activated brain areas in PKD patients were less than those of normal subject, and there was no activation in basal ganglia in PKD patients. During execution, the activation was also less in PKD patients except in bilateral M1.</p><p><b>CONCLUSION</b>During intermission, abnormalities of the brain still exist in PKD patients when during preparing or performing movement. The movement circuit in the brain displays an unusual state. The attack may be caused by reducing of inhibition in brain areas.</p>

Functional MRI of human brain in musicians and non-musicians / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To explore the differences in brain activation between musicians and non-musicians by use of functional MRI.</p><p><b>METHODS</b>Twelve right-handed musicians and twelve right-handed non-musicians were recruited in the study. During a listening task, they were scanned on the Sigma 1.5T scanner (GE) while they were passively listening to several segments of music of "the Butterfly Love" and the white noise with same physical energy.</p><p><b>RESULT</b>Both musicians and non-musicians demonstrated bilateral transverse gyrus weak activated while listening to the white noise. But when listening to music, they showed bilateral temporal areas strongly activated including superior temporal gyrus, transverse gyrus and some middle temporal areas. Moreover, musicians showed relative left dominance (10/12), whereas non-musicians demonstrated right dominance(11/12). Furthermore,besides bilateral temporal areas, more and stronger activated areas were found in musicians such as cuneus, precuneus,medial frontal and left middle occipital gyrus.</p><p><b>CONCLUSION</b>There are different neuro-patterns between musicians and non-musicians.</p>

Lateralized distribution of motor areas involved in voluntary movement / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the brain functional laterality in motor areas during motor execution systematically.</p><p><b>METHODS</b>Functional magnetic resonance imaging (fMRI) was employed combined with right hand sequential finger movement task to investigate brain activation pattern and laterality in 8 right-handed subjects. 3dDeconvolve program of AFNI was used to estimate the hemodynamic response function and to generate activation maps. Then the laterality index (LI) was calculated and tested statistically.</p><p><b>RESULT</b>All motor areas including the areas which were previously considered to be engage in movement preparation only were activated in movement execution. In the activation map, it appeared left lateralization in cerebra and right lateralization in cerebella. After further statistical test, it was found that in primary motor area (M1), supplementary motor area (SMA) and posterior parietal cortex (PPC), there were left lateralization. While in premotor cortex (PMC), cingulate gyrus and basal ganglia (BG), the lateralization tendency was not obvious. The activation in cerebella is characterized with right lateralization.</p><p><b>CONCLUSION</b>Though there are tiny differences among subjects, most of the motor areas appear lateralized activation. Past studies only observed laterality in several motor areas. It may be due to the difficulty of the task or the experimental design.</p>

Continuous representation of human portraits and natural scenery in human ventral temporal cortex: evidence from functional magnetic resonance imaging / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Functional magnetic resonance imaging (fMRI) has become a powerful tool for tracking human brain activity in vivo. This technique is mainly based on blood oxygenation level dependence (BOLD) contrast. In the present study, we employed this newly developed technique to characterize the neural representations of human portraits and natural sceneries in the human brain.</p><p><b>METHODS</b>Nine subjects were scanned with a 1.5 T magnetic resonance imaging (MRI) scanner using gradient-recalled echo and echo-planar imaging (GRE-EPI) pulse sequence while they were visually presented with 3 types of white-black photographs: natural scenery, human portraits, and scrambled nonsense pictures. Multiple linear regression was used to identify brain regions responding preferentially to each type of stimulus and common regions for both human portraits and natural scenery. The relative contributions of each type of stimulus to activation in these regions were examined using linear combinations of a general linear test.</p><p><b>RESULTS</b>Multiple linear regression analysis revealed two distinct but adjacent regions in both sides of the ventral temporal cortex. The medial region preferentially responded to natural scenery, whereas the lateral one preferentially responded to the human portraits. The general linear test further revealed a distribution gradient such that a change from portraits to scenes shifted areas of activation from lateral to medial.</p><p><b>CONCLUSIONS</b>The boundary between portrait-associated and scenery-associated areas is not as clear as previously demonstrated. The representations of portraits and scenes in ventral temporal cortex appear to be continuous and overlap.</p>

Memory deficit for the patients with mild cognitive impairment:A functional magnetic resonance imaging study / 中国康复理论与实践

@#ObjectiveTo provide the early diagnosis of Alzheimer\'s disease(AD), the memory in the patients with mild cognitive impairment(MCI) was detected under the functional magnetic resonance imaging(fMRI), combined with the behavioral experiment.Methods9 patients with MCI and 9 controls matched for the age, gender, level of education and handedness performed encoding and retrieval of nonsense line drawings, presented visually while the MR machine was scanning. ResultsCompared with the controls, the patients manifested longer reaction time and lower correct ratio. The patients\' brain activation showed: the first episode of encoding of nonsense line drawings elicited distributed activation in bilateral dorsal lateral frontal lobes, left parahippocampus, bilateral temporal-occipital conjunction, parietal lobes and visual cortex in the control subjects. While these activations decreased in the second episode of encoding of the same stimuli, much stronger activation was found in most same areas during the retrieval phase except for the right parietal lobe, in which the patients showed stronger activation. Moreover, activation in the anterior cingulate cortex was observed only in the retrieval phase. The patients showed weaker and smaller activation in almost all activation areas during all tasks in the normal subjects. ConclusionThe patients with MCI have the deficit in memory. The examination of encoding and retrieval of nonsense line drawings by means of the behavioral experiment and fMRI test can offer a powerful reference for the early diagnosis of AD.

Cortical language activation in aphasia: a functional MRI study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Functional neuroimaging has been used in neurolinguistic research on normal subjects and on patients with brain damage. This study was designed to investigate the differences of the neural basis underlying language processing between normal subjects and aphasics.</p><p><b>METHODS</b>Functional magnetic resonance imaging (fMRI) was used to map the language network in 6 normal subjects and 3 patients with aphasia who were in the stage of recovery from acute stroke. The participants performed a word generation task during multi-slice functional scanning for the measurement of signal change associated with regional neural activity induced by the task.</p><p><b>RESULTS</b>In normal subjects, a distributed language network was activated. Activations were present in the frontal, temporal, parietal and occipital regions. In the patient group, however, no activation was detected in the left inferior frontal gyrus whether the patient had a lesion in the left frontal lobe or not. Two patients showed activations in some right hemisphere regions where no activation appeared in normal subjects.</p><p><b>CONCLUSIONS</b>fMRI with word generation task is feasible for evaluating language function in aphasic patients. Remote effect of focal lesion and functional redistribution or reorganisation can be found in aphasic patients.</p>