Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, USA; Department of Psychology and Human Development, Vanderbilt University, USA; Department of Human Development and Quantitative Methodology, University of Maryland, USA.
Department of Psychology, University of Maryland, USA; Department of Neuroscience and Cognitive Sciences, University of Maryland, USA.
Neuropsychologia. 2020 Nov;148:107636. doi: 10.1016/j.neuropsychologia.2020.107636. Epub 2020 Oct 9.
The impact of stress hormones, such as cortisol, on the brain is proposed to contribute to differences in executive function of school-age children from impoverished backgrounds. However, the association between cortisol reactivity, prefrontal cortex, and executive function is relatively unexplored in young children. The current longitudinal study examined whether 63 children's early preschool-age (3-5 years, Time 1) and concurrent school-age (5-9 years, Time 2) salivary cortisol reactivity were associated with executive function and prefrontal cortical thickness at school-age. Two measures of cortisol reactivity were calculated: area under the curve with respect to ground (AUCg; total cortisol release) and with respect to increase (AUCi; total change in cortisol). Results demonstrated that Time 2 total cortisol release was negatively associated with executive function, Time 1 total cortisol release positively related to right middle frontal cortical thickness, and Time 2 total cortisol change was negatively associated with right inferior frontal cortical thickness. Moreover, greater right middle frontal cortical thickness mediated the association between greater Time 1 total cortisol release and lower executive function. This study provides support for an early adversity framework in which individual differences in executive function in childhood are directly related to the variations of cortisol-release and the effects on the prefrontal cortex thickness.
应激激素（如皮质醇）对大脑的影响被认为是导致贫困背景下学龄儿童执行功能差异的原因之一。然而，皮质醇反应性、前额叶皮质和执行功能之间的关系在幼儿中相对较少被探索。本纵向研究考察了 63 名儿童在学龄前（3-5 岁，时间 1）和同期学龄期（5-9 岁，时间 2）的唾液皮质醇反应性是否与学龄期的执行功能和前额叶皮质厚度有关。计算了两种皮质醇反应性的指标：基于基础的曲线下面积（AUCg；总皮质醇释放量）和基于增加的曲线下面积（AUCi；皮质醇总变化量）。结果表明，时间 2 总皮质醇释放与执行功能呈负相关，时间 1 总皮质醇释放与右侧额中回皮质厚度呈正相关，时间 2 总皮质醇变化与右侧额下回皮质厚度呈负相关。此外，更大的右侧额中回皮质厚度介导了时间 1 总皮质醇释放量与执行功能降低之间的关系。本研究支持了早期逆境框架，即儿童期执行功能的个体差异与皮质醇释放的变化直接相关，也与前额叶皮质厚度的变化相关。
