Research On The Brain Structural And Functional Bases Of Perfectionism And Their Relationships With Anxiety And Depression In An Undergraduate Sample

Perfectionism reflects one’s tendency to concern over making mistakes and doubt the quality of own actions excessively, which may affect one’s emotion. Little is known about the brain structural or functional bases associated with the perfectionism and negative emotion, though there has been so much behavioral research. To investigate the relationship among perfectionism, its brain structural and functional bases, and negative emotion like anxiety and depression, we conducted three studies as follows.In the first study, we aimed at duplicating the previous results about the relationship among perfectionism, anxiety and depression, and testifying the significant correlation between some of the sub-dimensions of perfectionism, and anxiety and depression respectively at the behavioral research level in our sample. In the second study, given that we had duplicated and proved the behavioral research results regarding the relationship between perfectionism and anxiety and depression, and based on the results in the first study, we aimed at exploring the brain structural bases associated with the perfectionism, and their potential association with anxiety and depression. In the third study, we aimed at further exploring the brain functional bases associated with the perfectionism, and their potential association with anxiety or depression based on these results in the first and second study.In the first study, we assessed the perfectionism of every participant via the Chinese Frost Multidimensional Perfectionism Scale, and employed the State-Trait Anxiety Inventory, STAI-Form Y, and the Beck Depression Inventory to collect their scores of anxiety and depression in our undergraduate sample. Results revealed that the scores of the two maladaptive sub-dimensions, concern over mistakes and doubts about actions were significantly positively correlated with the scores of the State-Trait Anxiety Inventory and the Beck Depression Inventory. But the score of organization, an adaptive factor, was significantly negatively correlated with the scores of the state anxiety and depression.Then, in the second study, a multiple linear regression analysis was conducted to identify regions where gray matter volume(GMV) was associated with individual differences in the sub-dimension scores of perfectionism at the whole-brain level based on the preprocessed structural imaging data. And based on the results in the study one, we only focused on the brain structural bases of the three sub-dimensions significantly correlated with anxiety or depression, namely concern over mistakes, doubts about actions and organization. Results uncovered that the score of concern over mistakes was positively correlated with the regional GMV of the right anterior cingulate cortex, insula, precentral gyrus, inferior frontal gyrus and superior temporal gyrus, and the left insula and inferior parietal lobule. And the score of organization was positively correlated with the regional GMV of the some parts of the left inferior frontal area. And meanwhile, the score of doubts about actions was positively correlated with the regional GMV of the anterior cingulate cortex, the left triangular part of the inferior frontal gyrus, middle frontal gyrus, supplementary motor area and medial frontal gyrus, as well as negatively correlated with the regional GMV of the left insula and the right postcentral gyrus. And furthermore, because the regional GMV of the anterior cingulate cortex did not only correlate with the score of doubts about actions positively, but also significantly positively correlated with the score of the state anxiety and depression, we found that the score of doubts about actions acted as a mediator both in the relationship between the regional GMV of the anterior cingulate cortex and the score of the state anxiety, and in the relationship between the regional GMV of the anterior cingulate cortex and the score of depression via the follow-up mediation analyses.Similarly, in the third study, a multiple linear regression analysis was conducted to identify regions whose functional connectivity was associated with individual differences in the sub-dimension scores of perfectionism at the whole-brain level based on the preprocessed functional imaging data. And based on the results in the study one and two, in the third study, we set the anterior cingulate cortex as a region of interest, and through the functional analyses we found that the functional connectivity between the anterior cingulate cortex and the superior / middle frontal gyrus, the functional connectivity between the anterior cingulate cortex and the precuneus, and the functional connectivity between the anterior cingulate cortex and the cerebellum were all significantly correlated with the score of doubts about actions. And these functional connectivity was correlated with the scores of individual anxiety or depression as well.In consideration of all the three studies and results above, perfectionism might have an impact on individual anxiety and depression to some extent. The anterior cingulate cortex, as a pivotal brain region in the cognitive and emotional processing, the GMV in it and the functional connectivity between it and other brain regions both significantly correlated with the score of perfectionism, anxiety and depression. All results might suggest the important role of the anterior cingulate cortex in the individual perfectionism, anxiety and depression. In sum, this research investigated the brain structural and functional bases of perfectionism, and provided novel evidence for perfectionism and negative emotional processing.