Department of General Psychology, University of Padova, Padova, Italy.
Department of Developmental Psychology and Socialization, University of Padova, Padova, Italy.
J Intellect Disabil Res. 2022 Jan;66(1-2):81-93. doi: 10.1111/jir.12904. Epub 2021 Dec 3.
Working memory (WM) is generally considered an area of weakness in the cognitive profile associated with Down syndrome (DS). The great majority of studies explored WM in this population through a comparison with typical development (TD) on the basis of mental age or developmental level. However, it is also relevant to understand how these skills develop and whether such development could be more related to chronological or developmental level. In the present study, we explored cross-sectional developmental trajectories of spatial-sequential and spatial-simultaneous WM in individuals with DS across chronological age and developmental level. Typically developing children (TD) of similar mental age were also included as a comparison group.
Eighty-four individuals with DS (aged between 7 and 30 years) and 327 children with TD (aged between 4 and 8 years) were administered with tasks to assess spatial-sequential and spatial-simultaneous WM, together with tasks to assess both general verbal and spatial developmental levels.
Performance in spatial-simultaneous WM task was lower compared with spatial-sequential WM task in both groups. In the case of individuals with DS, the developmental trajectories of chronological age are better described through a segmented model showing increased performance until approximately 13 years of age, followed by a rather flat progress. In the case of TD children, developmental trajectories are better described through a linear model in the spatial-simultaneous WM task when chronological age is considered; in the spatial-sequential WM, the increase in performance with age was however characterised by a discontinuity at age 6. The increase in performance followed a linear pattern in both groups (DS and TD) without substantial differences between the types of measure used (verbal vs. spatial) when the developmental level is considered.
工作记忆（WM）通常被认为是与唐氏综合征（DS）相关的认知特征中的一个弱点领域。绝大多数研究通过与典型发育（TD）进行心理年龄或发育水平的比较来探索该人群的 WM。然而，了解这些技能如何发展以及这种发展是否与实际年龄或发育水平更为相关也是很重要的。在本研究中，我们探索了 DS 个体在整个实际年龄和发育水平上的空间序列和空间同时 WM 的横断面发展轨迹。具有相似心理年龄的典型发育儿童（TD）也被纳入作为对照组。
对 84 名 DS 个体（年龄在 7 至 30 岁之间）和 327 名 TD 儿童（年龄在 4 至 8 岁之间）进行了空间序列和空间同时 WM 任务以及一般言语和空间发育水平任务的评估。
在两个组中，空间同时 WM 任务的表现均低于空间序列 WM 任务。对于 DS 个体，实际年龄的发展轨迹通过分段模型更好地描述，表现出直到大约 13 岁的增加，随后是相当平坦的进展。对于 TD 儿童，当考虑实际年龄时，空间同时 WM 任务的发展轨迹通过线性模型更好地描述；在空间序列 WM 中，随着年龄的增长，表现的增加表现出 6 岁时的不连续性。在考虑发育水平时，无论使用何种类型的测量（言语对空间），两组（DS 和 TD）的表现均呈线性增加，没有实质性差异。
