Changes In Resting Functional Connections At The Beginning Of Normal Brain Aging

Objective:To discover the differences and characteristics of default mode network and functional connectivities of the whole brain among younger,early middle-aged and elder middle-aged control by BOLD-IMRI resting imaging technology.Meanwhile,to explore the appilication of BOLD-IMRI resting imaging technology in this study and provide the evidence of the younger,early middle-aged and elder middle-aged.In early middle age,to investigate whether age-related cognitive differences predict rapidly changes in old age,and to intervene early in brain aging to prevent pathological aging.Methods:18 healthy young people(21 to 30 years old),18 middle-aged people(32 to 49 years old)and 21 middle-aged people(50 to 64 years old)were collected from the physical examination center of Hubei Cancer Hospital.The resting magnetic resonance imaging(MRI)data of the above grouped subjects were collected by the German Siemens 3.0t MRI scanner.The independent component analysis of the default network connection of the brain and the internal functional connection of the whole brain were used to conduct statistics and processing of the obtained data,and the differences of functional activity and internal functional connection of the brain in the three groups were compared on the whole.Results:In the process of cerebellum growing after matured,the junction of anterior lobe,dentate nucleus of cerebellum,posterior lobe vertebral body and posterior lower half of cerebellum all showed the trend of connection decline,while the connection of posterior lobe uvula,cerebellum peak and posterior lower half of cerebellum showed the trend of connection enhancement.The experimental results show that when early aging has more significant effect on the cerebellum,diminished in some areas of the cerebellum network connected.This may play an important role in age-related cognitive and motor decline in the cerebellum,while the brain creates new areas of activation to compensate for lost functionality.At the same time,we can find in the experimental results that the functional activation area of the cerebellum becomes larger in elder-middle aged people,which is generally bilateral activation.Therefore,the experimental results show that after the cerebellum senium,the cerebellum cannot be inactivated in the brain network connection in the resting state as young people do,which may affect the working efficiency of the brain network and affect people’s movement and executive ability.Default network: in the resting state,observe the early stages and development of brain aging with age as the variable axis.Parietal lobe changes in the parietal precuneus anterior segment,parietal lobe sub-gyral and parietal angular gyrus regions of the signal became weaker and weaker,the connection decreased.There was decreased connectivity in the upper,lower,and medial frontal lobes,but there were also enhancement.Once the prefrontal cortex is fully grown and is the more flexible structure in the brain.In the senility brain,most of the construction is build in the structure,and studies show that,in older people,high levels of activity in the prefrontal cortex are clearly associated with improved memory.At the beginning of grave changes in the brain,both the cingulate cortex(BA23,24,29,30,32)and the limbic cingulate gyrus showed reduced functional connections,while the cingulate gyrus(BA24,30,31,32)also showed activation signals.In the superior gyrus,inferior gyrus and temporal pole of the temporal lobe,there were enhanced activation signals in the inferior occipital gyrus,wedgeus and lingual gyrus,while there were also signs of gradual decline with age in the inferior gyrus and temporal pole of the temporal lobe.Whole brain connected function: during the period of 30 years old,the brain starts to change,in Brodmann13,Brodmann40,Brodmann45 activation intensity attenuation somewhat,in Brodmann6,Brodmann18,Brodmann19,Brodmann44 occipital tongue come back and the wedge and occipital lobe sub-gyral,thalamus after lateral nucleus,putamen and caudate nucleus,the medial globus pallidus,the insula these areas of activation.During the age of 50,Brodmann5,Brodmann19,Brodmann45,the legume nucleus and the dorsolateral region of the thalamus showed enhanced activation signals.Brodmann17,Brodmann40,and Brodmann44 declined.Conclusion:Among the youth group,the early middle age group and elder middle age group in the resting state,there is a large area of the brain function network weakening connection,especially in the transition from youth to early-middle age stage.this abnormal condition has both relationship with cognitive decline,as well as a local area and the function of the connection between brain areas,especially some advanced coordination control central brain regions.As the brain maturing,there are compensatory connections with age,and brain regions develop further,with lower or higher functional connections in middle-aged brains than in younger brains.