Functional MRI Research Of Default Mode Network And Spatial Working Memory Of Primary Insomnia

PartⅠ Functional MRI Research of Default Mode Network in primary insomniaObject:This experiment based on functional MRI technique, used functional connectivity method, and chosen bilateral posterior cingulate gyrus as seed region, investigated the default mode network of primary insomnia. And try to explore whether there is specific change of DMN and it potentially mechanism based on neuroimaging. And then, try to give support of objective evidence to clinical diagnosis and treatment of cognitive dysfunction in primary insomnia. And find some scientific basis to neurophysiological pathogenesis of cognitive dysfunction in primary insomnia based on functional MRI. Method:I Enrolled 30 cases Primary insomnia patients in according with diagnosis criteria of American Diagnostic and Statistical Manual of Mental Disorders 4th ed DSM- Ⅳand Chinese criteria of mental disorder(CCMD-3). And enrolled 30 cases health control, the gender and age was matched with primary insomnia group. All the subjects were did conventional MRI scan first, and exclude the cases if they have positive findings. All subjects participated the test of Pittsburgh sleep quality(PSQI), Hamilton anxiety scale(HAMA), Hamilton depression scale(HAMD) and spatial working memory associated scale. Compare the difference between health control group and primary insomnia group via two simple t test. All subjects’ conventional MRI image, resting state functional MRI data and task state f MRI data were conducted on 3T MRI scanner. And I used SPM8 and REST software to do the Data preprocessing. And then set PCC/p C as a seed region, compared the difference of DMN in primary insomnia and health control group. Results: 1 PI, HC group clinical scales result1.1 There is significant difference of PSQI, HAMD, HAMA and spatial working memory scale between primary insomnia group(PI group) and healthy control group(HC group).1.2 There was no significant difference of HAMA and PSQI between primary insomnia group with mild depression group and primary insomnia with moderate depression group. 2 Results of default mode network(DMN) of PI group and HC group.2.1 Default mode network of PI and HC group, the functional connectivity difference brain regions include: cingulated gyrus, prefrontal lobe, bilateral parietal lobe, parahippocampal gyrus, cortex of temporal lobe and occipital lobe.2.2 Compared with HC group, in insomnia group, the functional connectivity increased brain regions include bilateral superior frontal lobe and middle cingulated gyrus, the functional connectivity decreased regions include left occipital lobe, parahippocampal gyrus, left temporal lobe.2.3 Compared with Primary insomnia with mild depression group, in primary insomnia with moderate depression group, the functional connectivity increased brain regions include middle cingulated gyrus, right middle frontal lobe; the functional connectivity decreased brain regions include left parahippocampal gyrus. Conclusions:1. Primary insomnia group had basic clinical feature of sleep disorder and cognitive impairment. And anxiety and depression are main affective disorder of primary insomnia patients. There are no significantly correlation between anxiety and depression.2. PI group and HC group both had default mode network, and there were abnormal default mode network in PI group. The result revealed that there were cognitive dysfunction and emotional dysregulation in PI group, this still consistent with clinical scale.3. Middle cingulate gyrus is the brain region associated with depression, and associated with the degree of depression. And the extent of functional damage of hippocampus is correlated with the extent of insomnia.PartⅡ Functional MRI Research of Spatial Working Memory associated brain network in Primary Insomnia Object:This experiment based on functional MRI technique, used resting state f MRI and spatial working memory task f MRI ways to investigate abnormal spatial working memory associated brain network circuit loop and its’ mechanism in primary insomnia. I set right superior parietal lobule a seed region, to explore possibly neural network changes and mechanisms of disorder of spatial working memory in primary insomnia patients, and investigated the roles of right superior parietal lobe(BA7/5) in spatial working memory, and to find some scientific basis of neurophysiological pathogenesis of cognitive dysfunction in primary insomnia based on functional MRI. Method:I Enrolled 30 cases Primary insomnia patients in according with diagnosis criteria of American Diagnostic and Statistical Manual of Mental Disorders 4th ed(DSM-Ⅳ) and Chinese criteria of mental disorder(CCMD-3). And enrolled 30 cases healthy control, the gender and age was matched with primary insomnia group. All the subjects were did conventional MRI scan first, and exclude the cases if they have positive findings. All subjects participated the test of Pittsburgh sleep quality(PSQI), Hamilton anxiety scale(HAMA), Hamilton depression scale(HAMD) and spatial working memory associated scale. All subjects’ conventional MRI image, resting state functional MRI data and spatial working memory task f MRI data were conducted on 3T MRI scanner. And I used SPM8 and REST software to do the Data preprocessing. And then set right superior parietal lobe as seed region, compared resting state f MRI and spatial working memory task f MRI difference of spatial working memory. I Analyze brain network of spatial working memory and difference between healthy control group and primary insomnia group, and then, provide scientific evidence of imaging for cognitive dysfunction of primary insomnia.Results:1 Right superior parietal lobe(BA7/5) as seed region, resting state f MRI research of spatial working memory brain network in primary insomnia 1.1 The resting state f MRI of spatial working memory associated brain region in HC group which connected with right superior parietal lobe were bilateral parietal lobe, frontal lobe, parietal lobe, occipital lobe, right cerebellum hemisphere and parahippocampal gyrus. The intensity and range of functional connectivity of right hemisphere was higher and larger than left hemisphere.1.2 The resting state f MRI of spatial working memory associated brain region in PI group which connected with right superior parietal lobe were bilateral parietal lobe, frontal lobe, parietal lobe, occipital lobe, cerebellum hemisphere, left precuneus and posterior cingulate gyrus. The intensity and range of functional connectivity of right hemisphere was higher and larger than left hemisphere. 1.3 Compared with HC group, the functional connectivity between bilateral of frontal lobe, postcentrol gyrus, and left precuneus and right superior parietal lobe increased in PI group. The functional connectivity between right cerebellar hemisphere, parahippocampal gyrus, occipital lobe, left putamen and right superior parietal lobe decreased in PI group. 2 Spatial working memory tasking state f MRI results of PI and HC group 2.1 In HC group, when do the spatial working memory task, the brain regions under activation include bilateral cortex of parietal lobe, frontal lobe, temporal lobe, occipital lobe, insula lobe, thalamus and pons, midbrain. 2.2 In PI group, when do the spatial working memory task, the brain regions under activation include bilateral cortex of parietal lobe, frontal lobe, temporal lobe, occipital lobe, insula lobe, left parahipocampal gyrus, thalamus, right pons 2.3 In PI group, compared with HC group, the more activation was demonstrated in left temporal lobe, occipital lobe and right frontal lobe. And the activation of bilateral parahippocampal gyrus, temporal lobe, frontal lobe and superior parietal lobe decreased. Conclusions:1. Spatial working memory was implemented by multi brain regions collaborate. And there were specific brain network of spatial working memory, the brain regions were bilateral cortex of parietal lobe, frontal lobe, temporal lobe and occipital lobe, bilateral insula, cerebellar hemisphere, pons, thalamus and so on. The bilateral superior parietal lobes were key brain regions of spatial working memory. And the dominant hemisphere of spatial working memory was right hemisphere.2. Right superior parietal lobe as seed region, the resting state functional network of spatial working memory almost same as spatial working memory task functional network. Which means right superior parietal lobe was the core component of spatial working memory; right superior parietal lobe could be the seed region of spatial working memory research.3. Primary insomnia patients had abnormal spatial working memory brain network, which revealed the brain network mechanism of spatial working memory loss, cognitive dysfunction and affective disorder.