School of Nursing, University of Rochester Medical Center, Rochester, NY, United States.
Department of Psychiatry, University of Rochester Medical Center, Rochester, NY, United States.
Neuroimage Clin. 2018 Jul 23;20:297-304. doi: 10.1016/j.nicl.2018.07.021. eCollection 2018.
Locus of control (LOC) is an important personality trait. LOC over cognitive competency reflects an individual's perceived control of desired cognitive outcomes, which is critical for maintaining successful cognitive aging. It is important to understand the neural substrates of LOC over cognitive competency in older adults, especially for individuals at high risk of dementia. Here, we characterized a cohesive functional and structural connectivity profile underlying LOC among 55 older adults with amnestic mild cognitive impairment (aMCI), combining resting-state functional magnetic resonance imaging and diffusion tensor imaging. The results showed that both functional and structural connectivity between the medial prefrontal cortex and amygdala were significantly correlated with external LOC. The functional connectivity mediated the correlation between structural connectivity and external LOC. In addition, aging-associated neurodegeneration moderated the relationship between structural connectivity and external LOC, showing that the structural connectivity was positively correlated with external LOC in low, but not high neurodegeneration. Our results suggest a critical role of the functional amygdala-frontal network, which may serve as a bridge between its white matter tract and LOC over cognitive competency in groups at high risk for dementia.
控制点（LOC）是一个重要的人格特质。认知能力的控制点反映了个体对期望认知结果的感知控制，这对于维持成功的认知老化至关重要。了解老年人认知能力控制点的神经基础很重要，特别是对于那些有痴呆症高风险的个体。在这里，我们结合静息态功能磁共振成像和弥散张量成像，对 55 名有遗忘型轻度认知障碍（aMCI）的老年人进行了研究，描述了 LOC 背后的一致的功能和结构连接特征。结果表明，内侧前额叶皮层和杏仁核之间的功能和结构连接都与外部 LOC 显著相关。功能连接介导了结构连接和外部 LOC 之间的相关性。此外，与衰老相关的神经退行性变调节了结构连接和外部 LOC 之间的关系，表明在低神经退行性变组中，结构连接与外部 LOC 呈正相关，而在高神经退行性变组中则没有。我们的结果表明，功能杏仁核-前额叶网络起着关键作用，它可能是其白质束和认知能力控制点之间的桥梁，对于痴呆症高危人群来说尤其如此。
