Objective To explore the impacts of childhood traumatic experience of depression patients on the brain function and personality characteristics.Methods A matched case-control study design was used to recruit the outpatients of Department of Psychiatry,the First Affiliated Hospital of Chongqing Medical University.Depression patients with or without childhood traumatic experience (observation group or control group,n=25) were matched by age,gender,years of education,and severity of depression.The resting state functional magnetic resonance brain spontaneous amplitude of low-frequency fluctuation (mALFF) signal,functional connectivity (FC) and the neuroticism extraversion openness five-factor inventory (NEO-FFI) were used as observation indexes to compare the differences between the 2 groups.Results Corrected by the Gauss random field (GRF) with voxel level P<0.001 and mass level P<0.05,the mALFF signal values in the left hippocampus/parahippocampal gyrus and in the right precuneus in the observation group were significantly lower than those in the control group.There were no significant differences between the 2 groups in extraversion,openness,agreeableness or responsibility of NEO-FFI (all P>0.05),while the score of neuroticism in the observation group was significantly higher than that in the control group (P<0.01).There were negative correlations between neuroticism score and mALFF signal value in left hippocampus/left parahippocampal gyrus or right precuneus in both groups (r=-0.397,P<0.01;r=-0.401,P<0.01).Compared with the control group,the functional connection between the left hippocampus and the right superior temporal gyrus was increased,and the functional connection between the left hippocampus and the left central posterior gyrus was decreased in the observation group.Conclusion The function of left hippocampus/left parahippocampal gyrus and right precuneus is more greatly impaired in depression patients with childhood traumatic experience,and they have more neurotic personality traits.At the same time,this study suggests that there may be a brain protective neuroimaging mechanism to shield the excessive arousal of traumatic memory.