A Resting-state Functional Magnetic Resonance Imaging Study In Primary Insomnia Of Brain

Objective：Using technology of resting-state functional magnetic resonance imaging (rs-fMRI),we want to probe the neurobiological mechanisms of brain activity of patientswith primary insomnia from the local and overall level.Methods:20PI patients diagnosed by psychiatrist(DSM-IV) in my hospital and20healthy controls were included in this study.By observing differences of regionalhomogeneity (ReHo) firstly between patients with Primary Insomnia(PI)and HealthyControl(HC)by applying the resting state fMRI, we analyzed the differences degree offunction synchronization in regional cerebral.Then we made correlation analysis withReHo value of areas of different ReHo between the two groups and PSQI score.Lastly we made LACC as region of interest and analyze its functional connectivityfeatures with the whole brain through seed-based correlation analysis method.Results:1、Compared with HC,PI had lower ReHo value in following regions: bilateralbasal ganglia(including putamen,lentiform nucleus),bilateral anterior cingulatecortical,bilateral pons,right medial prefrontal cortex,right posterior cingulate cortical,right frontal gyrus,right cerebellum lobe, left amygdala, left superior frontal gyrus,leftposterior cerebellum,etc; PI had higher ReHo value in following regions:bilateraloccipital lobe(including lingual gyrus),bilateral precentral gyrus,right postcentralgyrus,right posterior cerebellum lobe,right triangle of inferior frontal gyrus,rightsuperior temporal gyrus,right orbital of left middle frontal gyrus,left orbitofrontalcortex,etc.2、Among areas of different ReHo value between the two groups,We only foundthe ReHo value in left anterior cingulate cortex (LACC) of PI group are negativelycorrelated with PSQI score (r=-0.54，p=0.014).3、Compared with HC,the function connectivity of LACC in PI decrease infollowing brain:bilateral inferior parietal lobule(including precuneus), right putamen, right lentiform nucleus,right inferior frontal gyrus(including mPFC and orbital frontalgyrus),left insula, left middle occipital gyrus,etc; the function connectivity of LACCin PI only increase on the right posterior cerebellum lobe.Conclusion:1、Local brain activity in brain regions of PI in arousal system (ascendingreticular activating system of brain stem),brain regions related to advanced cognitivefunction(mPFC,basal ganglia,angular gyrus,temporal lobe and cerebellum),emotionregulation system (amygdala,cingulate cortical,basal ganglia)show abnormal,and weguess it is likely to be the pathophysiology mechanism of sleep disorder,socialfunction differences,mood changes and dysfunction of cognitive system(attention andmemory)in PI patients.Occipital lobe and sensorimotor regions show highconsistency on patients with PI.This is probable because of hyperarousal ofsensorimotor cortex,the restoring or compensation of information-processingfunction.2、The worse sleep quality of PI patients,the lower of ReHo value in LACC.Thehighly correlation between ReHo value and LACC can reflect the degree of sleepdisorders in PI patients to some extent,and may be a important biological indicator ofpreclinical diagnosis in PI patients.3、The decreasing function connectivity of LACC in PI patients with basalganglia and DMN (including inferior parietal lobule,precuneus,prefrontal gyrus)maybe the heoretical basis of mood disorders and the dysfunction of the advancedcognitive function.