Resting State Functional Connectivity In Patient With Mild Cognitive Impairment

Objective: Resting-state functional magnetic resonance imaging(rs-fMRI)was used to investigate the abnormal functional connectivity in patients with mild cognitive impairment(MCI).Method: In this study,a case-control study was conducted to select 32 people in the MCI group and 34 in the normal control(NC)group matched by gender,age and years of education.The cognitive function of the subjects was evaluated using a neuropsychological scale,and the whole brain resting state functional magnetic resonance scan was performed on MCI and NC using a 3.0T magnetic resonance imaging system.First,the Amplitude of low-frequency fluctuation(ALFF)method was used to analyze the differences in brain spontaneous activity between NC and MCI patients.Secondly,the brain regions with different differences were defined as regions of interest,and the brain functional connectivity map was obtained based on the seed-based analysis method.finally,the functional connectivity differences between the two sets of these seed points were compared.Result: 1.There were no statistical differences in gender,age,and years of education between the MCI group and the NC group(P>0.05).2.Compared with the NC group,the MCI group had statistical differences(P<0.05)in the total score of ADAS and ADAS-Cog.3.Compared with the NC group,the ALFF value of the MCI group mainly showed that the increased brain area mainly had medial frontal gyrus,left medial superior frontal gyrus,left precentral gyrus,posterolateral prefrontal cortex,anterior motor cortex and auxiliary movement,inferior gyrus frontalis,right postcentral gyrus,right supramarginal gyrus,right superior parietal gyrus,and inferior parietal lobule were all statistically significant.4.The ALFF values of medial frontal gyrus,left medial superior frontal gyrus,left precentral gyrus,posterolateral prefrontal cortex,anterior motor cortex and auxiliary movement,inferior gyrus frontalis were negatively correlated with the score of ADAS-Cog(r =-0.421,P<0.05).5.Compared with the NC group,the MCI group the MCI group had enhanced functional connectivity between the right angular gyrus and the right postcentral gyrus,right supramarginal gyrus,right superior parietal gyrus,and inferior parietal lobule.Conclusion: 1.MCI patients have cognitive impairment.2.Compared with NC group,the ALFF value of MCI group increased,mostly concentrated in the frontal and parietal lobes,and the ALFF value of frontal lobes was correlated with neuropsychological test scores,suggesting that the abnormal brain spontaneous activity in these areas of MCI patients may be involved in the cognitive impairment process of MCI.3.Enhanced functional connectivity between the right angular gyrus and frontal lobe ALFF abnormal brain regions in patients with MCI.Not only indicates that the increased ALFF in the frontal lobe is abnormal in the local brain function,but also reveals that patients with MCI have abnormal functional connection between the frontal lobe and the parietal lobe,suggesting that abnormal local spontaneous activity in the frontal lobe and changes in the functional connection between the frontal lobe and the parietal lobe may be potential biomarkers identified by MCI.