A Study Of The Functional Magnetic Resonance Imaging Of Linguistic-functional Cortex And Functional Connectivity In Motor Aphasia Patients During Resting State

Part I:A study of the fMRI of Chinese semantic and phonetic taskObjective:Language is peculiar to human brain important function, Chinese as the world’s most populous language, its neural mechanisms may be with different from the alphabet writing, to investigate the related activation brain which participate in Chinese language processing in language tasks of normal volunteer using based on blood oxygenation level dependent (BOLD) effect of functional magnetic resonance imaging (fMRI) in this section mainly, thus provides the basis for clinical preoperative localization and aphasia nerve recovery mechanism.Methods:15healthy volunteers whose mother tongue is Chinese, normal right-handed, normal language function, and no history of mental illness and other neurological carried on the BOLD fMRI scan. The semantics judgment and phonetic judgment was executed in the scanning. Selected primary language function area——Broca area and Wernicke area for interested area (Region of interest, ROI). Application of brain function post-processing software AFNI software processed image. According to different task requirements calculated average brain activation map at a group level. Extracted the mean signal rate of change of Broca area, Wernicke area, and subregion of Broca in two languages tasks,and set out the two time signal intensity in the region. According to the formula of LI=(L-R)/(L+R), compared two partial lateralization index in linguistic judgment tasks. Results:Multiple functional brain areas which were distributed in the frontal lobe,parietal lobe,occipital lobe,temporal lobe and cerebellum hemispheres were activated in the semantic judgment and phonetic judgment task. Both language tasks could effectively activate the Broca area and Wernicke area, and showed a lightly trend of the left side of the partial lateralization. The signal intensity of the left inferior frontal gyrus BA45/47area in the semantic judgment task was stronger than the phonetic judgment task; and the signal intensity of its back side BA44/45region in the phonetic judgment task was stronger than the semantic judgment task. There was no different in the time signal intensity of the Broca area and Wernicke area in the two language tasks.Conclusion:1The primary language brain areas,such as Broca area and Wernicke area, were activated in the semantic judgment task and the phonetic judgement task.2The right hemisphere also participate in the Chinese language semantic and phonetic processing, cortical reaction characterized by lightly left lateralization tendency.3The ventral of left inferior frontal gyrus BA45/47was specificity activated in the semantic judgment task; and its dorsal BA44/45was specificity activated in the phonetic judgment task. Part II:A Study of the fMRI of the repeatability of linguistic-functional cortexObjective:To investigate the reproducibility and stability of brain functional area of average volunteers in the response of language tasks during Chinese word processing with blood oxygen level dependent functional magnetic resonance imaging (BOLD-fMRI)by follow-up scanning, and to provide a basis for the clinical preoperative localization and mechanisms of recovery from aphasia.Methods:Research data was collected by scanning the semantic judgment and phonologic judgment of15right-handed healthy volunteers with Chinese as their mother-tongue and normal language function. The scanning was conducted twice with BOLD-fMRI, with same experiment tasks and time interval being one month.Such main brain language-functional areas as Broca’s area and Wernicke’s area are selected as the region of interest (ROI).By analyzing the effective overlapping average activation maps, the accumulated number activated in ROI is calculated, and the language fMRI reproducibility of different subjects are estimated.The specific activation of the semantic judgment and phonologic judgment in Broca’s area is confirmed by drawing the time course of the two language tasks in sub-areas of Broca’s area. The laterality index of the two language judgment tasks are compared based on the equation LI=(L-R)/(L+R).By individually calculating the spatial distance of ROI centroid coordinates in the same activating range before and after the test, the inter-subjects stability in between-session is calculated quantitatively.Result:Multi brain areas distributed in both cerebral hemispheres, such as forehead, parietal, pulvinar, and temporal lobe,and in both cerebellar hemispheres are activated by the semantic judgment and phonologic judgment tasks.Both language tasks induced significant BOLD response in Broca’s area and Wernicke’s area, with a tendency of left lateralization.The signal reaction of semantic judgment is more intense than that of phonologic judgment in the left inferior frontal lobe anteroventral BA45/47region, and the singal reaction of phonologic judgment is more intense than that of semantic judgment in the BA44/45region of dorsal.The number of subjects in terms of the activation of both language tasks in Broca’s area and Wernicke’s area accounts more than half of the total subjects, Note that semantic judgment task showed better reproducibility in Broca’s area, comparing to the phonologic judgment task. It is indicated that in the same spatial distance of ROI centroid coordinates, the stability of Broca’s area is higher than that of Wernicke’s area, and the stability of semantic judgment in Broca’s area is higher than that of phonologic judgment.Conclusion:1Broca’s area and Wernicke’s area can be effectively activated by both semantic judgment and phonologic judgment.2By comparison, semantic judgment in Broca’s area shows a higher level of reproducibility and stability, thus is feasible for the study of clinical preoperative localization and mechanisms of recovery from aphasia. Part Ⅲ:A Study of the fMRI of functional connectivity in ischemia stroke motor aphasia patients during resting stateObjectives:To study the changes of functional brain areas inpatients with motor aphasia under resting-state by using functional connectivity.Materials and Methods:Resting-state sequence scanning were performed using GE Signa HDx3.0T magnetic resonance scanner in ischemic stroke motor aphasia and normal controls. After acquired all the subjects’resting-state images data,the data was then preprocessed and statistical analysis by relevant software. Then, used functional connectivity analysis method to calculate the two groups of resting state for the brain functional connectivity change situation. Selected Talairach (49-,17,5) and its mirror image area Talairach (49,17,5) as the center coordinate of the ROI, to6voxels for radius, on behalf of Broca area and its mirror image area, with the whole brain all other voxel’s time sequence did correlation analysis. The results did single sample t test in the two groups, and did two sample t test between the two groups. After statistical map overlaid to the MNI brain, according to the template tag with known anatomic markers to describe the statistically significant areas of the brain, and record the size of mass (cluster), the size of the brain area and MNI coordinates and related strength, with "t" said, t value is bigger,the correlation is stronger.Results:After removed subjects’influence factors,such as head moving, and10ischemic stroke motor aphasia patients and10normal controls entered the results analysis.Normal control group resting state and a positive correlation between Broca area of the brain area mainly include:bilateral inferior frontal gyrus, basal ganglia, insular lobe,knee of corpus callosum, the brain stem, left superior frontal gyrus,angular gyrus,superior temporal gyrus,middle temporal gyrus, rectum gyrus, middle occipital gyrus,infeiror occipital gyrus,cerebellum, and right inferior parietal lobule.Motor aphasia patients group and normal control group resting state and Broca area of positive correlation between brain areas are mainly:bilateral posterior cingulate gyrus, precuneus, splenium of corpus callosum, parahippocampal gyrus, cerebellum, left precentral gyrus, superior frontal gyrus, middle frontal gyrus,inferior frongtal gyrus, medial frontal gyrus, superior temporal gyrus, middle temporal gyrus, supramarginal gyrus, angular gyrus, superior occipital gyrus, rectum gyrus, hippocampus, right lingual gyrus, fusiform gyrus, tonsil of cerebellum, left brain stem. And Broca area was negatively correlated with the brain area mainly include:knee of corpus callosum, anterior cingulate gyrus, bilateral superior frontal gyrus, medial frontal gyrus, superior temporal gyrus, right precentral gyrus, postcentral gyrus, middle frontal gyrus,inferior frongtal gyrus,middle temporal gyrus, cuneus, lobular lobe,superior parietal lobule,inferior parietal lobule,basal ganglia,middle occipital gyrus, left cerebellum.Motor aphasia patients group and normal control group resting state and Broca area mirror image area of the positive correlation between brain areas mainly include:posterior cingulate gyrus, precuneus, cuneus, splenium of corpus callosum, brain stem,bilateral superior frontal gyrus, medial frontal gyrus, lingual gyrus, hippocampal gyrus,left middle temporal gyrus,fusiform gyrus,hippocampus,superior occipital gyrus,right middle frontal gyrus,inferior frontal gyrus,thalamus,fusiform gyrus, parietal lobe, superior temporal gyrus, middle temporal gyrus, inferior temporal gyrus,cerebellum.And Broca area image area was negatively related to the brain area mainly include:bilateral medial frontal gyrus, cingulate gyrus,cerebellum,knee of corpus callosum,left superior frontal gyrus, middle frontal gyrus,inferior frontal gyrus, precentral gyrus, postcentral gyrus,superior parietal lobule,inferior parietal lobule, superior temporal gyrus, middle temporal gyrus, inferior temporal gyrus,insular lobe, middle occipital gyrus, inferior occipital gyrus,supramarginal gyrus, basal ganglia,right postcentral gyrus, rectum gyrus. Conclusions:1There is a wide range of motor network language function during resting-state.2The right parahippocampal gyrus,lingular gyrus,fusiform gyrus,cerebellum, tonsil and splenium of corpus callosum may have certain significance for ischemic stroke motor aphasia patients with motor language recovery.3The knee of corpus callosum,left frontal cortex and insular lobe is of great significance to maintain normally motor language function,and right inferior parietal lobule and rectum gyrus may participate in maintaining normal motor language function.