Morphological connectivity correlates with trait impulsivity in healthy adults.

Jingguang Li,Xiang-Zhen Kong

doi:10.7717/peerj.3533

Abstract

BackgroundImpulsivity is one crucial personality trait associated with various maladaptive behavior and many mental disorders. In the study reported here, we investigated the relationship between impulsivity and morphological connectivity (MC) between human brain regions, a newly proposed measure for brain coordination through the development and learning.MethodTwenty-four participants’ T1-weighted magnetic resonance imaging (MRI) images and their self-reported impulsivity scores, measured by the Barratt impulsiveness scale (BIS), were retrieved from the OpenfMRI project. First, we assessed the MC by quantifying the similarity of probability density function of local morphological features between the anterior cingulate cortex (ACC), one of the most crucial hubs in the neural network modulating cognitive control, and other association cortices in each participant. Then, we correlated the MC to impulsivity scores across participants.ResultsThe BIS total score was found to correlate with the MCs between the ACC and two other brain regions in the right hemisphere: the inferior frontal gyrus (IFG), a well-established structure for inhibition control; the inferior temporal gyrus (ITG), which has been previously shown to be associated with hyperactive/impulsivity symptoms. Furthermore, the ACC-IFG MC was mainly correlated with motor impulsivity, and the ACC-ITG MC was mainly correlated with attentional impulsivity.DiscussionTogether, these findings provide evidence that the ACC, IFG, and ITG in the right hemisphere are involved neural networks modulating impulsivity. Also, the current findings highlight the utility of MC analyses in facilitating our understanding of neural correlates of behavioral and personality traits.

Highlights

Impulsivity, ‘‘a predisposition toward rapid, unplanned reactions to internal or external stimuli without regard to the negative consequences of these reactions to the impulsive individual or to others’’ (Moeller et al, 2001), is one crucial personality trait that may influence many facets of human life
Individual differences in impulsivity showed a positive association with the anterior cingulate cortex (ACC)-inferior frontal gyrus (IFG) morphological connectivity (MC) (Fig. 2B; r = 0.64, p = 0.001, SE = 0.097; 95% confidence interval (CI) [0.32, 0.83]; Spearman’s rho = 0.43, p = 0.035), and showed a negative association with the ACC-inferior temporal gyrus (ITG) MC (Fig. 2C; r = −0.59, p = 0.004, SE = 0.18; 95% CI [−0.80, −0.24]; Spearman’s rho = −0.53, p = 0.008)
We found that the observed associations between MCs and impulsivity measures remained after controlling for head size, suggesting that our findings were unlikely contributed by head size

Summary

Introduction

Impulsivity, ‘‘a predisposition toward rapid, unplanned reactions to internal or external stimuli without regard to the negative consequences of these reactions to the impulsive individual or to others’’ (Moeller et al, 2001), is one crucial personality trait that may influence many facets of human life. Trait impulsivity has been associated with variability of white-matter integrity in several brain parts, such as anterior corpus callosum (Moeller et al, 2005), inferior frontal and anterior cingulate regions (Romero et al, 2010) These findings suggest that trait impulsivity reflects the function of different neural circuits, and highlight the vital roles of certain structures (e.g., IFG, ACC, and OFC) in impulsive control. The BIS total score was found to correlate with the MCs between the ACC and two other brain regions in the right hemisphere: the inferior frontal gyrus (IFG), a wellestablished structure for inhibition control; the inferior temporal gyrus (ITG), which has been previously shown to be associated with hyperactive/impulsivity symptoms. The current findings highlight the utility of MC analyses in facilitating our understanding of neural correlates of behavioral and personality traits

Methods

Results

Discussion

Conclusion