Contribution of child development, biological aging, and beta-amyloid to cognitive function of the Louisville twins at midlife

项目总结/摘要 我们目前资金的首要目标（NIH资助#R 01 AG 063949 -01）是重新利用路易斯维尔双胞胎 研究的最初目标是了解儿童认知发展到真正寿命的病因 认知的发育双胞胎研究，包括临床前症状的病因学描述 阿尔茨海默氏病及相关痴呆症。在本项目期间，第三个独立目标 包括认知发展对中年认知功能的建模影响， 混杂遗传和环境因素。在路易斯维尔双胞胎研究（LTS）的整个过程中， 然而，记录的能力分数已经年龄标准化，因此无法估计 在任何发展时期认知能力的真正个体内变化。年龄问题- 标准化的方法通过实施不同的测试（例如，moving from the 韦氏儿童智力量表（WISC）到韦氏成人智力量表（WAIS））和测试 版本（例如，从WAIS-III更新到WAIS-IV），据称可以测量相同的潜在认知能力 能力.他们是否真的这样做是一个经验性的问题，以前没有在任何 认知能力的双胞胎纵向研究所有LTS双胞胎的认知能力协议都是可用的，所以个人 项目可用于今后的分析。我们建议使用垂直链接方法， 而不需要年龄标准化的认知测试分数。儿童和成人测试 内容通常是不一样的，但有一些项目，在童年时期，可以管理， 在成人测试中保留。对于当前的数据收集，来自WISC Block的三个适合年龄的项目 将对所有返回的LTS进行设计、相似性、词汇、算术和信息子测试 成人（预计N = 750）。作为孩子，LTS双胞胎完成了大约10项认知能力测试， 平均值，其中一半是WISC测试。估计对每对双胞胎实施了五项WISC方案， 平均而言，有超过73，000个单独的子测试用于存档和垂直链接儿童和成人 韦氏能力得分。项目反应理论模型随后可用于将能力得分 相同的量表，以便可以研究和比较儿童和成人不同时期的能力趋势 发展因此，双胞胎的潜在认知能力测试分数将从7岁到10岁采用相同的量表。 中年我们在LTS中的努力是认知能力纵向双胞胎研究中的第一次。通过链接 儿童认知测试到成人测试，我们将通过以下方式增加我们发现的重要性和创新性： 在子测验和潜在因子水平上确定能力的寿命增长函数， 双胞胎真正的个体内认知能力轨迹。

Project Summary/Abstract The overarching aim of our current funding (NIH Grant # R01 AG063949-01) is to repurpose the Louisville Twin Study’s original goal of understanding the etiology of child cognitive development into a true lifespan developmental twin study of cognition, including delineation of the etiology of preclinical symptoms of Alzheimer’s disease and related dementias. In the current project period, the third independent aim encompasses modeling effects of cognitive development on cognitive functioning in midlife, adjusting for confounding genetic and environmental factors. Throughout the life of the Louisville Twin Study (LTS), however, recorded ability scores have been age standardized, thus making it impossible to estimate effects of true intraindividual change in cognitive ability over any period of development. Problems with the age- standardized approach are compounded by the administration of different tests (e.g., moving from the Wechsler Intelligence Scale for Children (WISC) to the Wechsler Adult Intelligence Scale (WAIS)) and test editions (e.g., updating from the WAIS-III to the WAIS-IV) that supposedly measure the same latent cognitive abilities. Whether they actually do so is an empirical question that has not been addressed previously in any longitudinal twin study of cognitive ability. All LTS twins’ cognitive ability protocols are available, so individual items could be used in future analyses. We propose using vertical linking methods that allow the administration of validated cognitive tasks without requiring age-standardizing cognitive test scores. Child and adult test content typically is not the same, but there are some items that were administered in childhood that can be retained in adult tests. For the current data collection, three age-appropriate items from the WISC Block Design, Similarities, Vocabulary, Arithmetic, and Information subtests will be administered to all returning LTS adults (projected N = 750). As children, LTS twins completed approximately 10 cognitive ability tests, on average, half of which were WISC tests. With an estimated five WISC protocols administered to each twin, on average, there are greater than 73,000 individual subtests to archive and vertically link child and adult Wechsler ability scores. Item Response Theory models subsequently can be used to place ability scores on the same scale so that ability trends can be studied and compared across different periods of child and adult development. Twins’ latent cognitive ability test scores, thus, will be put on the same scale from age 7 through midlife. Our efforts in the LTS are the first of its kind in longitudinal twin studies of cognitive ability. By linking childhood cognitive tests to adult tests, we will increase the significance and innovation of our findings by specifying the lifespan growth functions of ability at the subtest and latent factor levels to model individual twins’ true intraindividual cognitive ability trajectories.