The Role of the Hippocampus in Early Memory for Words

项目摘要 情景记忆，或者说是用特定细节记住过去事件的能力，对人类来说是至关重要的。 经验，并与各种领域的学习和适应功能有关。在典型的发展中 对于儿童来说，情景记忆的改善出现在婴儿期，并在幼儿期及以后得到改善。 尽管早期情景记忆能力显著，但大多数早期记忆都因婴儿期健忘症而丢失， 个体无法回忆发生在生命最初2或3年的事件。发展过程中， 海马被假设为主要负责情节记忆的早期出现， 儿童和早期记忆的丧失，由于婴儿健忘症。然而，这些假设是基于 在早期人类发育中的非人类模型和体内研究受到以下因素的显著限制： 获取神经成像数据的方法学挑战，特别是与任务相关的功能性神经成像 数据，来自幼儿。 最近对成年人的研究强调，海马体参与了最初记忆的获得。 在新单词和它们的参照物之间的任意关联，海马神经元中的一种能力明显受损， 失忆我们建议利用婴儿和蹒跚学步的孩子们非凡的单词学习技能来探索 单词记忆的神经基质是否可以用作早期情景记忆的标记。 这项研究将探索新的方法来测试婴儿海马结构和功能， 18至30个月大的幼儿，在此期间，情景记忆得到改善，数百个单词被 学习，但婴儿健忘症运作。 与公共卫生的相关性：健康的情景记忆为疾病的出现和发展提供了基础。 自传体记忆的发展，自我从过去到未来的连续性，并与 智力和学术成就。情节记忆的发展受到损害， 轻度后天性神经损伤、焦虑和抑郁等心理健康状况，以及 神经发育障碍;语言习得在许多疾病中额外受损 强调记忆和词汇发展的特征是理解适应性的关键， 在不同的儿童群体中发挥作用。

PROJECT SUMMARY Episodic memory, or the ability to remember past events with specific detail, is central to the human experience and is related to learning and adaptive functioning in a variety of domains. In typically developing children, episodic memory improves emerges during infancy and improves during early childhood and beyond. Despite remarkable early episodic memory skills, most early recollections are lost to infantile amnesia, individuals' inability to recall events occurred in the first 2 or 3 years of life. Developmental processes within the hippocampus are hypothesized to be primarily responsible for both the early emergence of episodic memory in children and the loss of early recollections due to infantile amnesia. However, these hypotheses are based on non-human models and in-vivo investigations in early human development have been significantly limited by the methodological challenge of acquiring neuroimaging data, particularly task-related functional neuroimaging data, from young children. Recent studies in adults have highlighted that the hippocampus is involved in the acquisition of the initially arbitrary association between new words and their referents, a capacity markedly impaired in hippocampal amnesia. We propose to leverage the remarkable word-learning skills in infants and toddlers to explore whether neural substrates of memory for words can be used as a marker of early episodic memory. The proposed research will explore new methods to test hippocampal structure and function in infants and toddlers ages 18 to 30 months, a period during which episodic memory improves, hundreds of words are being learned, but infantile amnesia operates. Relevance to Public Health: Healthy episodic memory provides a foundation for the emergence and development of autobiographical memory, continuity of self from past to future, and is associated with intellectual ability and academic achievement. The development of episodic memory is impaired following even mild forms of acquired neurological insult, mental health conditions such as anxiety and depression, and neurodevelopmental disorders; language acquisition is additionally impaired in a number of disorders underscoring that a characterization of memory and vocabulary development is key to understanding adaptive functioning in various populations of children.