Stress effects on childhood brain development

压力对儿童大脑发育的影响

• 批准号: 8645130
• 负责人: Allyson Patricia Mackey
• 金额: $ 5.15万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8645130
• 关键词: 6 year old; Adult; Affect; Age; Animal Experimentation; Brain; Brain region; Buffers; Child; Childhood; Chronic stress; Cognition; Cognitive; Complex; Data; Development; Diffusion; Education; Environment; Environmental Risk Factor; Event; Exhibits; Figs - dietary; Functional Magnetic Resonance Imaging; Goals; Human; Impaired cognition; Income; Inferior; Intervention; Knowledge; Lateral; Life; Light; Link; Liquid substance; Literature; Magnetic Resonance Imaging; Measures; Medial; Mental Health; Mental disorders; Neurosciences Research; Occupations; Outcome; Parietal Lobe; Pattern; Performance; Physiological; Physiology; Prefrontal Cortex; Process; Recruitment Activity; Research; Rest; Risk; Short-Term Memory; Socioeconomic Status; Stress; Sum; Symptoms; Testing; Thick; Variant; Weight; Work; association cortex; cognitive neuroscience; coping; experience; hydrocortisone receptor; indexing; innovation; insight; low socioeconomic status; novel; processing speed; public health relevance; response; skills; white matter

DESCRIPTION (provided by applicant): The goal of this research is to investigate the effects of stress on childhood brain development. While low levels of stress during development can promote healthy coping later in life, chronic stress sets up vulnerabilities for psychiatric disorders and impairs cognition. Although chronic stress cannot be experimentally manipulated in humans, it is possible to investigate the effects of naturally occurring variations in stress exposure. Childhood socioeconomic status (SES), an index composed of parental education, occupation, and income, is linked to a gradient in exposure and reactivity to stress. Lower SES is associated with more stressful life events and greater dysregulation of stress physiology. Further, low SES environments are associated with fewer factors that buffer the effects of stress. Recent animal research has provided evidence that stress might accelerate important maturational processes. This is problematic in light of the finding in humans that slower brain development is associated with superior cognitive skills. I propose to test the novel hypothesis that stress accelerates brain development in young children. Further, I will explore the question of whether early brain maturation is an adaptive response to a high-stress environment. To test these hypotheses, I will recruit six-year-old children from low SES backgrounds who have experience many stressful life events (high-stress group, N=40), and children from high SES backgrounds who have experienced few stressful life events (low-stress group, N=40). I will 1) characterize differences in perceived stress, physiological stress markers, and cognitive performance between high- and low-stress groups; 2) test whether the high-stress group exhibits greater structural brain maturity as indexed by greater cortical thickness and more directional diffusivity in white matter; 3) explore whether structural maturation differences are reflected in functional networks; and 4) investigate whether early maturation in the high-stress group is associated with inferior or superior cognitive abilities and mental health. In high-stress environments, accelerated maturation may be adaptive because it protects networks supporting cognitive skills in a partially developed state, rendering them less vulnerable to environmental insult. In sum, this research will be the first to test the innovative hypothesis that stress accelerates brain development in young children, and to explore whether accelerated development is an adaptive response to stress. Results of this study will help fill a major gap in knowledge that has evolved from the underrepresentation of children from low SES backgrounds in cognitive neuroscience research. Our findings will elucidate the neurodevelopmental mechanisms by which childhood stress impacts cognition and increases risk for psychiatric illness. Knowledge gained from this work will provide insight into whether interventions should aim to accelerate or decelerate brain maturation in children exposed to stress.

描述（由申请人提供）：本研究的目的是调查压力对儿童大脑发育的影响。虽然在发展过程中的低水平压力可以促进以后生活中的健康应对，但长期压力会导致精神疾病的脆弱性并损害认知。虽然慢性压力不能在人类身上进行实验操作，但有可能研究压力暴露中自然发生的变化的影响。儿童社会经济地位（SES），一个由父母教育，职业和收入组成的指数，与压力暴露和反应的梯度有关。较低的SES与更多的压力生活事件和更大的压力生理失调有关。此外，低SES环境与缓冲压力影响的因素较少有关。最近的动物研究提供的证据表明，压力可能会加速重要的成熟过程。这是有问题的，因为在人类中发现，大脑发育较慢与上级认知技能有关。我建议测试新的假设，即压力加速幼儿的大脑发育。此外，我将探讨大脑早期成熟是否是对高压力环境的适应性反应。为了验证这些假设，我将招募来自低社会经济地位背景的6岁儿童，他们经历了许多压力生活事件（高压力组，N=40），以及来自高社会经济地位背景的儿童，他们经历了很少的压力生活事件（低压力组，N=40）。我将1）描述高压力组和低压力组之间感知压力、生理压力标记和认知表现的差异; 2）测试高压力组是否表现出更大的大脑结构成熟度（以更大的皮质厚度和白色物质中更定向的扩散率为指标）; 3）探索结构成熟度差异是否反映在功能网络中;以及4）调查高压力组的早熟是否与较差或上级认知能力和心理健康有关。高应力 在某些环境中，加速成熟可能是适应性的，因为它保护了支持处于部分发展状态的认知技能的网络，使它们不那么容易受到环境损害。总之，这项研究将是第一个测试压力加速幼儿大脑发育的创新假设，并探索加速发育是否是对压力的适应性反应。这项研究的结果将有助于填补一个主要的知识空白，从低SES背景的儿童在认知神经科学研究中的代表性不足。我们的研究结果将阐明儿童压力影响认知和增加精神疾病风险的神经发育机制。从这项工作中获得的知识将提供深入了解干预措施是否应该旨在加速或减缓暴露于压力的儿童的大脑成熟。