Childhood Poverty and Brain Development: The Role of Chronic Stress and Parenting

描述（由申请人提供）：五分之一的美国儿童在贫困中长大。虽然有充分的证据表明，这对健康、成就和社会情绪调整有害，但人们对调节贫困有害影响的大脑基础知之甚少。在这个研究项目中，我们解决了两个相关的主要问题：(1)童年贫困如何影响成人的大脑结构和功能？(2）. 什么潜在的机制可以解释儿童贫困与大脑的关系？我们假设慢性生理应激失调以及童年时期严厉、无反应的父母教育将解释童年贫困与成年大脑结构和功能之间的一些预期联系，特别是在海马体、杏仁核和前扣带/内侧前额叶皮层。这项工作将与康奈尔大学的发展心理学家埃文斯（Evans）进行的一项为期14年、持续进行的低收入和中等收入个体纵向研究项目相结合，该项目主要关注儿童贫困、生理压力和社会情感发展。这个样本中有一半（现在22岁）是在贫困线以下长大的，一半是中等收入家庭。从社会经济地位和其他人口统计学变量，以及身体和心理风险暴露来看，样本在整个生命过程中都有很好的特征。该纵向队列的主要结果变量包括生理应激（神经内分泌、心血管和代谢）的多种方法学指标，以及父母、自我和教师对社会情感发展（内化、外化、自我调节）的评价。关于养育子女的深入数据也包括在内。神经成像工作将在密歇根大学精神学系进行，由擅长健康和精神疾病压力神经成像的Liberzon和研究育儿大脑基础的儿童精神病学家Swain共同完成。脑部扫描将分为3个阶段：第一个阶段将获取高分辨率图像，用于体积和皮质厚度分析。此外，选择性情绪注意任务和情绪评价/再评价任务将探测杏仁核-前额叶回路的功能。在扫描二中，由婴儿哭声和图片组成的育儿刺激将被用来激活被认为与育儿行为和社会互动有关的神经回路。此外，工作记忆、延迟贴现和行为抑制任务将测试皮质-皮质和皮质-海马体回路中的皮质抑制、决策。最后，在第三次fMRI扫描之前，将进行Trier社会压力测试，该测试在实验室环境中可靠地产生升高的皮质醇水平。随后的扫描将直接评估急性应激诱导后的大脑功能，并允许与这些受试者的基线大脑功能进行比较，包括重复选择性情绪注意任务、育儿任务和情绪面部评估任务，以重新检查杏仁核、海马体和前额皮质的表现。这些实验利用了一个独特的具有良好特征的低收入和中等收入个体纵向样本，并结合了一套全面的概念衍生，创新但也经过验证的神经影像学范式。这个项目的目的是研究童年贫困对大脑的潜在影响。我们将研究与慢性压力和亲子互动有关的大脑区域。

DESCRIPTION (provided by applicant): One fifth of America's children grow up in poverty. While there is good evidence that this is harmful to health, achievement, and socio-emotional adjustment, very little is known about the brain basis that mediates the detrimental effects of poverty. We address two related primary questions with this research project: (1) How does childhood poverty influence adult brain structure and function? (2). What underlying mechanisms might account for childhood poverty - brain relationships? We hypothesize chronic physiological stress dysregulation as well as harsh, unresponsive parenting during childhood will account for some of the expected linkages between childhood poverty - adult brain structure and function - particularly in the hippocampus, amygdala, and the anterior cingulate/medial prefrontal cortex. This work will piggyback onto a 14 year, ongoing longitudinal research program of low and middle-income individuals focused on childhood poverty, physiological stress, and socio-emotional development conducted by Evans, a developmental psychologist at Cornell. Half of this sample (now age 22) grew up below the poverty line and half middle income. The sample is well characterized over their life course in terms of SES and other demographic variables, as well as both physical and psychosocial risk exposures. Primary outcome variables for this longitudinal cohort include multiple methodological indicators of physiological stress (neuroendocrine, cardiovascular, and metabolic) along with parental, self, and teacher ratings of socioemotional development (internalization, externalization, self regulation. In depth data on parenting are also included. The neuroimaging work will be conducted in the Department of Psychiatry, University of Michigan by Liberzon, with expertise in the neuroimaging of stress in health and mental illness, and by Swain a child psychiatrist studying the brain basis of parenting. Brain scanning will be divided into 3 sessions: the first will acquire high resolution images for volumetric and cortical thickness analyses. In addition, a selective emotional attention task as well as an emotion appraisal/re- appraisal task will probe the functionality of amygdala-prefrontal circuits. With scan two, parenting stimuli consisting of baby cries and pictures will be used to activate circuits believed to relate to parenting behavior and social interactions. Furthermore, working memory, delayed discounting and behavioral inhibition tasks will test cortical inhibition, decision-making, in cortico-cortical and cortico-hippocampal circuitry. Finally, immediately prior to the third fMRI scan, a Trier Social Stress Test that reliably generates elevated cortisol levels in laboratory environment will be performed. The subsequent scans will directly assess brain function following acute stress induction, and allow comparison with the baseline brain function in these same subjects, including a repetition of the selective emotional attention task, the parenting task and the emotional face assessment task to re-examine amygdala, hippocampus and prefrontal cortex performance. These experiments utilize a uniquely well-characterized longitudinal sample of low- and middle-income individuals in combination with a comprehensive set of conceptually derived, innovative but also validated neuroimaging paradigms. The aim of this project is to examine the potential impacts of childhood poverty on the brain. We will examine areas of the brain well studied in relation to chronic stress and parent-child interactions.