NEUROBEHAVIORAL OUTCOME OF PEDIATRIC HEAD INJURY

该项目的目标是评估遭受创伤性脑损伤(TBI)的儿童在多个领域的神经行为结果：认知、行为和运动。该假说认为额叶损伤的性质和程度是年龄和损伤严重程度以外预后差异显著的原因。基于MRI的结果，研究了脑局灶性病变与认知后遗症的关系，特别是执行功能。创伤性脑损伤是美国儿童最常见的死亡原因(病死率从3/100例到14/100例不等)和后天脑损伤(180/100,000例住院病例的发生率)，也是导致发育障碍的主要原因。据估计，美国每年有1.7万名儿童因头部损伤而致残，原因是执行功能(EFS)缺陷，如解决问题和规划问题，以及记忆、注意力、阅读、算术、运动、精神和适应行为领域的障碍。尽管大多数严重闭合性脑损伤(CHI)患者在传统的智力和语言功能测试中恢复到正常范围，但我们发现EF缺陷仍然存在于解决问题、计划、反应调节和口头和书面叙述的产生方面。发展认知理论家将EFS视为(1)维持未来目标的问题解决集合；(2)随着时间的推移组织行为；(3)有序地解决问题；(4)巧妙地使用策略；(5)灵活而有效的语言自我调节；(6)能够改变儿童随后做出反应的概率的反应或动作(即对反馈的反应)；以及假设EFS依赖于前额叶区域的成熟和完整性。我们研究了EF缺陷与CHI的病理生理学之间的关系，发现61%的重度CHI儿童有前额叶病变。工作记忆和抑制(定义如下)是基本的交互过程，涉及更复杂的技能，如解决问题、推理、计划、阅读和听觉理解、算术和自我调节，而元认知技能是使儿童能够评估自己的知识、监控他们的认知活动和部署策略的综合能力。我们假设，这些成分的完整性对儿童话语加工、学业成绩和适应行为的发展至关重要，而抑制和元认知技能与儿童CHI的精神结局有关。目的1探讨涉及工作记忆、抑制和元认知技能的特定EF缺陷与CHI的急性严重程度、局灶性脑损伤的成像和年龄差异的关系。目标2和目标3代表了一个新的方向，研究工作记忆、抑制和元认知技能完整性的变异性与儿童CHI的话语、学习成绩、适应行为和精神结果之间的关系。因此，该项目将认知结构与脑成像和结果领域相结合，包括发育神经精神病学，目的是改善对脑损伤儿童的评估和干预。

The goals of this project are to evaluate neurobehavioral outcomes in multiple domains: cognitive, behavioral, and motoric, for children who sustain traumatic brain injury (TBI). The hypothesis is that the nature and extent of injury to the frontal lobes account for significant variability in outcome beyond age and injury severity. Based on MRI findings, the relationship of focal brain lesions to cognitive sequelae, particularly executive functions, are investigated. Traumatic brain injury is the most common cause of death (case fatality rate ranging from 3 to 14/100 cases) and acquired brain insult (incidence of 180/100,000 hospitalized cases) in children in the U.S. and a major contributor to developmental disability. An estimated 17,000 children are disabled by head injury each year in the U.S. due to deficient executive functions (EFs) such as problem solving and planning as well as impairments in memory, attention, reading, arithmetic, motor, psychiatric, and adaptive behavior domains. Despite recovery of most severe closed head injury (CHI) patients to the normal range on traditional tests of intellectual and language functions, we have found that EF deficits persist on measures of problem solving, planning, response modulation, and production of oral and written narratives. Developmental cognitive theorists view EFs as (1) maintenance of a problem solving set for future goals; (2) organization of behavior over time; (3) orderly approaches to problems; (4) skillful use of strategies; (5) flexible and effective verbal self-regulation; (6) responses or actions that function to alter the probability of a subsequent response of the child (i.e., responsiveness to feedback); and postulate that EFs depend on the maturation and integrity of the prefrontal region. We have examined the relationship between EF deficits and the pathophysiology of CHI and identified that 61% of children with severe CHI had prefrontal lesions. Working memory and inhibition (defined below) are fundamental, interactive processes involved in more complex skills such as problem solving, inferencing, planning, reading and aural comprehension, arithmetic, and self-regulation, whereas metacognitive skills are integrative abilities enabling children to assess their knowledge, monitor their cognitive activities, and deploy strategies. We hypothesize that the integrity of these components of EFs is crucial to the development of discourse processing, academic achievement, and adaptive behavior while inhibition and metacognitive skills are related to the psychiatric outcome of CHI in children. Aim 1 addresses the relationship of specific EF deficits involving working memory, inhibition, and metacognitive skills to the acute severity of CHI, imaging of focal brain lesions, and age differences. Aims 2 and 3 represent a new direction which investigates how variability in the integrity of working memory, inhibition, and metacognitive skills is related to discourse, academic achievement, adaptive behavior, and psychiatric outcomes of CHI in children. This project thus integrates cognitive constructs with brain imaging and outcome domains which include developmental neuropsychiatry with the goal of improving assessment and interventions for brain injured children.