The Magnetic Resonance Imaging Study On Brain Structure And Resting-state Function For The Subjects With Congnitive Vulnerability To Depression

Objective:Using functional magnetic resonance imaging (fMRI), we examined the features of brain structure and brain function in resting state in subjects with cognitive vulnerability to depression (CVD), and explored their specificity of the biomarker, in order to provide new clue to neurobiological basis of CVD associated with phathophysiological mechanism.(1) To examine the gray matter volume abnormalities on brain three dimension structures of young adult subjects with CVD compared with matched first-episode medication-naive patients with major depressive disorder (MDD) and healthy controls (HC) using voxel-based morphometry (VBM) approach following MRI.(2) To examine the abnormalities in brain spontaneous activity in subjects with CVD compared with MDD patients and HC using resting-state functional magnetic resonance imaging (rs-fMRI).Methods:(1) Using the Cognitive Style Questionnaire (CSQ) and the Center for Epidemiologic Studies Depression Scale (CESD),642undergraduates in two universities were assessed and got595subjects with effective data. The weakest scores were computed based on the the theory of weakest link and scores of CSQ. According to the weakest scores of each subj ects, we got subj ects with CVD and HC.(2)30subjects with CVD,33first-episode medication-naive young adult patients with MDD and32age, gender and educational level matched HC were scanned using1.5T MRI, VBM approach on Statistical Parametrical Mapping was used to analyze the data, and the VBM gray matter volume of the three groups were compared.(3)32subjects with CVD,32first-episode medication-naive young adult patients with MDD and35age, gender and educational level matched HC were scanned during resting state for300s. ReHo and ALFF analysis were used to detect neural spontaneous activity and the between-group differences in ReHo and ALFF values were compared.Results:(1) Psychological measure results:The CESD scores of MDD group were significantly larger than those of either the HC or CVD group, while the CESD scores were not significantly differences between the HC and CVD groups. The weakest scores of the three groups were significantly different from each other, CVD> MDD> HC.(2) The results of gray matter volume:Using the whole-brain search approach, we found significant volumetric differences between the three groups. Post hoc analyses showed reduced gray matter volume in the left precentral gyrus (Brodmann area (BA)6) and right fusiform gyrus (BA 19) in subjects with CVD compared to controls, while patients with MDD had reduced gray matter volume in the precentral gyrus (BA6) and increased gray matter volume in the right thalamus. Additionally, subjects with CVD had a significantly smaller right fusiform gyrus (BA19) and right thalamus than patients with MDD.(3) The results of rs-fMRI:ALFF analysis:We found significant differences in ALFF value between the three groups using one-way analysis of variance (ANOVA). Post hoc analyses showed decreased ALFF in the bilateral orbitofrontal cortex (OFC)(BA11, BA10, BA47) and increased ALFF in the left insula (BA13) in subjects with CVD compared to controls, similarly patients with MDD had reduced ALFF in the bilateral OFC (BA11, BA10, BA47) and increased ALFF in the bilateral insula (BA13). Additionally, there were not significant ALFF between subjects with CVD and patients with MDD.ReHo analysis:We found significant differences in ReHo value between the three groups using one-way analysis of variance (ANOVA). Post hoc analyses showed decreased ReHo in the right cerebellum (BA17, BA18) and right OFC (BA10, BA11), and increased ReHo in the right posterior cingulate cortex (BA31) in subjects with CVD compared to controls, while patients with MDD had reduced ReHo in the bilateral OFC (BA10, BA11) and left superior frontal gyrus (BA6), increased ReHo in the right insula (BA13), right posterior cingulated cortex (BA31) and left fusiform gyrus (BA37). Additionally, subjects with CVD had decreased ReHo in the right cerebellum (BA17, BA18), and increased ReHo in the left superior frontal gyrus (BA6) and left middle frontal gyrus (BA10) than patients with MDD.Conclusion:(1) The results provide evidence for similar abnormalities of gray matter volume in both CVD subjects and MDD patients. Reductions of gray matter volume in the left precentral gyrus might be correlated to the cognitive vulnerability to depression, as well as an increased risk for depression.(2) Compared to controls, the abnormalities of neural spontaneous activity exist in the OFC and insula area in both CVD subjects and MDD patients, which implicates hypo-functioning of emotion regulation in the affective network, and might be the neural basis of cognitive vulnerability to depression.