PDF(Pubmed)
Abstract：
BACKGROUND: In vivo myeloarchitectonic mapping based on Magnetic Resonance Imaging (MRI) provides a unique view of gray matter myelin content and offers information complementary to other morphological indices commonly employed in studies of autism spectrum disorder (ASD). The current study sought to determine if intracortical myelin content (MC) and its age-related trajectories differ between middle aged to older adults with ASD and age-matched typical comparison participants.
METHODS: Data from 30 individuals with ASD and 36 age-matched typical comparison participants aged 40-70 years were analyzed. Given substantial heterogeneity in both etiology and outcomes in ASD, we utilized both group-level and subject-level analysis approaches to test for signs of atypical intracortical MC as estimated by T1w/T2w ratio.
RESULTS: Group-level analyses showed no significant differences in average T1w/T2w ratio or its associations with age between groups, but revealed significant positive main effects of age bilaterally, with T1w/T2w ratio increasing with age across much of the cortex. In subject-level analyses, participants were classified into subgroups based on presence or absence of clusters of aberrant T1w/T2w ratio, and lower neuropsychological function was observed in the ASD subgroup with atypically high T1w/T2w ratio in spatially heterogeneous cortical regions. These differences were observed across several neuropsychological domains, including overall intellectual functioning, processing speed, and aspects of executive function.
CONCLUSIONS: The group-level and subject-level approaches employed here demonstrate the value of examining inter-individual variability and provide important preliminary insights into relationships between brain structure and cognition in the second half of the lifespan in ASD, suggesting shared factors contributing to atypical intracortical myelin content and poorer cognitive outcomes for a subset of middle aged to older autistic adults. These atypicalities likely reflect diverse histories of neurodevelopmental deficits, and possible compensatory changes, compounded by processes of aging, and may serve as useful markers of vulnerability to further cognitive decline in older adults with ASD.
METHODS: Data from 30 individuals with ASD and 36 age-matched typical comparison participants aged 40-70 years were analyzed. Given substantial heterogeneity in both etiology and outcomes in ASD, we utilized both group-level and subject-level analysis approaches to test for signs of atypical intracortical MC as estimated by T1w/T2w ratio.
RESULTS: Group-level analyses showed no significant differences in average T1w/T2w ratio or its associations with age between groups, but revealed significant positive main effects of age bilaterally, with T1w/T2w ratio increasing with age across much of the cortex. In subject-level analyses, participants were classified into subgroups based on presence or absence of clusters of aberrant T1w/T2w ratio, and lower neuropsychological function was observed in the ASD subgroup with atypically high T1w/T2w ratio in spatially heterogeneous cortical regions. These differences were observed across several neuropsychological domains, including overall intellectual functioning, processing speed, and aspects of executive function.
CONCLUSIONS: The group-level and subject-level approaches employed here demonstrate the value of examining inter-individual variability and provide important preliminary insights into relationships between brain structure and cognition in the second half of the lifespan in ASD, suggesting shared factors contributing to atypical intracortical myelin content and poorer cognitive outcomes for a subset of middle aged to older autistic adults. These atypicalities likely reflect diverse histories of neurodevelopmental deficits, and possible compensatory changes, compounded by processes of aging, and may serve as useful markers of vulnerability to further cognitive decline in older adults with ASD.
摘要：
背景：基于磁共振成像（MRI）的体内骨髓结构作图提供了灰质髓鞘含量的独特视图，并提供了与自闭症谱系障碍（ASD）研究中常用的其他形态学指标互补的信息。当前的研究旨在确定患有ASD的中老年人和年龄匹配的典型比较参与者之间的皮质内髓磷脂含量（MC）及其与年龄相关的轨迹是否不同。
方法：分析了30名ASD患者和36名年龄匹配的40-70岁典型对照参与者的数据。考虑到ASD的病因和结局的实质性异质性，我们使用了组水平和受试者水平的分析方法来测试通过T1w/T2w比率估计的非典型皮质内MC的体征。
结果：组水平分析显示，各组间平均T1w/T2w比率或其与年龄的关联没有显著差异，但显示出年龄的显著正的双边主要影响，在大部分皮质中，T1w/T2w比率随着年龄的增长而增加。在主题级分析中，根据是否存在异常T1w/T2w比率的簇，将参与者分为亚组，在ASD亚组中观察到较低的神经心理功能，在空间异质的皮质区域中T1w/T2w比率非典型地高。这些差异在几个神经心理学领域被观察到，包括整体智力功能，处理速度,以及执行功能方面。
结论：这里采用的群体水平和受试者水平的方法证明了检查个体间变异性的价值，并提供了对大脑结构与认知之间关系的重要初步见解。ASD的寿命，提示部分中老年孤独症患者存在导致非典型皮质内髓磷脂含量和认知结局较差的共同因素。这些非典型现象可能反映了神经发育缺陷的不同历史，以及可能的补偿性变化，加上衰老的过程，并可能作为ASD老年人进一步认知能力下降的有用标志。
方法：分析了30名ASD患者和36名年龄匹配的40-70岁典型对照参与者的数据。考虑到ASD的病因和结局的实质性异质性，我们使用了组水平和受试者水平的分析方法来测试通过T1w/T2w比率估计的非典型皮质内MC的体征。
结果：组水平分析显示，各组间平均T1w/T2w比率或其与年龄的关联没有显著差异，但显示出年龄的显著正的双边主要影响，在大部分皮质中，T1w/T2w比率随着年龄的增长而增加。在主题级分析中，根据是否存在异常T1w/T2w比率的簇，将参与者分为亚组，在ASD亚组中观察到较低的神经心理功能，在空间异质的皮质区域中T1w/T2w比率非典型地高。这些差异在几个神经心理学领域被观察到，包括整体智力功能，处理速度,以及执行功能方面。
结论：这里采用的群体水平和受试者水平的方法证明了检查个体间变异性的价值，并提供了对大脑结构与认知之间关系的重要初步见解。ASD的寿命，提示部分中老年孤独症患者存在导致非典型皮质内髓磷脂含量和认知结局较差的共同因素。这些非典型现象可能反映了神经发育缺陷的不同历史，以及可能的补偿性变化，加上衰老的过程，并可能作为ASD老年人进一步认知能力下降的有用标志。
