Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, MR-Research Department, Section 714, Copenhagen University Hospital Hvidovre, Kettegaard Allé 30, 2650 Hvidovre, Denmark; Center for Integrated Molecular Brain Imaging, Copenhagen, Denmark; Institute of Technology, Metropolitan University College, Copenhagen, Denmark.
Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, MR-Research Department, Section 714, Copenhagen University Hospital Hvidovre, Kettegaard Allé 30, 2650 Hvidovre, Denmark; Center for Integrated Molecular Brain Imaging, Copenhagen, Denmark; Center for Human Development, University of California San Diego, La Jolla, United States.
Neuropsychologia. 2018 Jun;114:1-10. doi: 10.1016/j.neuropsychologia.2018.04.010. Epub 2018 Apr 11.
Neuroticism is a fundamental personality trait that reflects a tendency to experience heightened negative affect and susceptibility to stress. Negative emotionality has been associated with fronto-limbic brain structures and connecting fibre tracts. The major fibre tracts connecting the frontal and limbic brain regions are the cingulum bundle and uncinate fasciculus. We previously found that healthy adults with higher neuroticism scores had decreased left relative to right fractional anisotropy (FA) of the cingulum. Both cingulum and uncinate fasciculus FA increases throughout childhood and into early adulthood. Since adolescence is associated with an increased incidence of anxiety and mood disorders, for which neuroticism is a known risk factor, the question arises whether the association between neuroticism and fronto-limbic white matter microstructure asymmetry is already present in children and adolescents or whether such relationship emerges during this age period. To address this question, we assessed 72 typically-developing 10-to-15 year-olds with diffusion-weighted imaging on a 3 T magnetic resonance scanner. Neuroticism was assessed with the Junior Eysenck Personality Questionnaire. FA and parallel and perpendicular diffusivity measures were extracted for cingulum, uncinate fasciculus as well as the white matter underlying the ventromedial prefrontal cortex. Higher neuroticism scores were associated with decreased left relative to right cingulum FA in boys, while in girls, higher neuroticism scores were associated with increased left relative to right cingulum and ventromedial prefrontal white matter FA, indicating that there are sex differences in the neural correlates of neuroticism. Our findings suggest that the link between neuroticism and frontal-limbic white matter microstructure asymmetry likely predates early adolescence. Future studies need to elucidate the significance of the observed sex differences in the neural correlates of neuroticism.
神经质是一种基本的人格特质，反映了一种易体验到强烈负面情绪和易受压力影响的倾向。负面情绪与额-边缘脑结构和连接纤维束有关。连接额叶和边缘脑区的主要纤维束是扣带束和钩束。我们之前发现，神经质得分较高的健康成年人左侧扣带束相对于右侧的分数各向异性（FA）降低。扣带束和钩束的 FA 在整个儿童期和成年早期都有增加。由于青春期与焦虑和情绪障碍的发生率增加有关，而神经质是这些疾病的已知风险因素，因此出现了这样一个问题，即神经质与额-边缘白质微观结构不对称之间的关联是否已经存在于儿童和青少年中，或者这种关系是否在这个年龄段出现。为了解决这个问题，我们使用 3T 磁共振扫描仪对 72 名发育正常的 10 至 15 岁儿童进行了弥散加权成像评估。使用青少年艾森克人格问卷评估神经质。为扣带束、钩束以及腹内侧前额叶下的白质提取 FA 和平行与垂直方向弥散度测量值。在男孩中，神经质得分较高与左侧扣带束相对于右侧扣带束 FA 降低有关，而在女孩中，神经质得分较高与左侧扣带束和腹内侧前额叶白质 FA 相对于右侧 FA 增加有关，这表明神经质的神经相关性存在性别差异。我们的研究结果表明，神经质与额-边缘白质微观结构不对称之间的联系可能早于青春期早期。未来的研究需要阐明神经质神经相关性中观察到的性别差异的意义。
