The Role And Mechanism Of Overgeneral Autobiographical Memory In Patients With Treatment-resistant Depression

Objective:In this study,questionnaire survey and resting functional magnetic resonance imaging(f MRI)were used to explore the characteristics of overgeneral autobiographical memory and resting functional magnetic resonance imaging(f MRI)in patients with treatment-resistant depression from the point of view of low frequency amplitude.To understand the psychological and neural mechanism of treatment-resistant depression by analyzing the results of questionnaire and resting functional magnetic resonance imaging.Method:A case-control study was conducted to collect 34 patients aged 18-60 with treatment-resistant depression and 30 normal controls matched in sex,age and education.In the treatment-resistant depression group,24 items of Hamilton Depression Scale(HAMD-24)and Autobiographical Memory Test(AMT)were used to evaluate the degree of depression and overgeneral autobiographical memory.3.0 T resting f MRI was performed in patients with treatment-resistant depression and normal controls respectively.Brain imaging data and questionnaire scores were analyzed by using MATLAB R2013 b software(mainly SPM8,DPABI4.3,REST1.8 software package)and SPSS22.0.Brain areas with significant changes in ALFF values between the two groups were calculated(P﹤0.01).The differences of m ALFF values between the two groups were analyzed.Finally,treatment-resistant depression was suppressed,the correlation between m ALFF and depression and overgeneral autobiographical memory was analyzed.Results: 1.There were significant positive correlation between the total score of depression and the total score of autobiographical memory test in patients with treatment-resistant depression(P﹤0.05).2.The m ALFF values of left middle temporal gyrus,right superior temporal gyrus,right inferior frontal gyrus,left middle frontal gyrus,left dorsolateral superior frontal gyrus,left inferior parietal margin angular gyrus,right superior parietal gyrus and right dorsolateral superior frontal gyrus in the treatment-resistant depression group were significantly higher than those in the control group.3.There was a significant positive correlation between m ALFF value and HAMD score in the left inferior orbital frontal gyrus,right superior orbital frontal gyrus,left middle temporal gyrus,right inferior temporal gyrus,left anterior cingulate gyrus,left inferior insular cap frontal gyrus and left middle occipital gyrus(Alphasim correction,P ﹤ 0.05),and a significant negative correlation between right parahippocampal gyrus and left paracentral lobule.(Alphasim correction,P﹤0.05).4.The correlation between m ALFF value and AMT score in patients with treatment-resistant depression showed a significant positive correlation in the right fusiform gyrus,bilateral superior temporal gyrus,bilateral middle temporal gyrus,right lingual gyrus,left middle frontal gyrus,left parietal gyrus and right supplementary motor area(Alphasim correction,P﹤0.05).Conclusion: 1.There are more serious abnormal spontaneous neuronal activity in temporal lobe,frontal lobe,parietal lobe and other brain regions in patients with treatment-resistant depression.2.Depressive symptoms in patients with treatment-resistant depression may be related to abnormal local spontaneous nerve activity in frontal,temporal and occipital lobes.3.Overgeneral autobiographical memory may be related to abnormal local spontaneous nerve activity in occipital,temporal,frontal and parietal lobes.