Background: Hearing and visual impairments are common in individuals with Down syndrome (DS), yet it remains unclear whether sensory impairments are associated with cognitive and behavioural functioning such as language, memory and socialisation. This literature review examines those associations.

Methods: A scoping review of four databases was conducted to examine associations between sensory impairments and cognitive or behavioural outcomes in individuals with DS. Study evidence was assessed based on design, sample size, assessment modalities and statistical significance.

Results: Of 1471 studies screened, 38 met inclusion criteria. Hearing impairments were associated with delays in language and motor development during infancy, lower overall cognitive ability and social communication difficulties in childhood and reduced adaptive functioning and intellectual decline in adulthood. Visual impairments were linked to learning difficulties in childhood and to declines in adaptive behaviour, visual-motor integration and cognitive performance in adulthood. Subdomains of cognitive functioning such as memory, reasoning or processing speed were not reported for adults.

Conclusion: Uncorrected hearing and visual impairments in individuals with DS are associated with a range of cognitive and behavioural outcomes across the lifespan. The strongest associations were observed between hearing impairments and language delays in infancy and childhood, and between visual impairments and adaptive behaviour challenges in childhood and adulthood. Sensory impairments were associated with challenges in similar domains-particularly language, adaptive functioning and learning-across the lifespan. This suggests a potential continuity of these associations over time and that long-standing uncorrected impairments may be associated with reduced cognitive reserve and increased vulnerability to decline-highlighting the need for early identification and intervention.

Keywords: behavioural functions; cognitive functions; down syndrome; hearing impairments; scoping review; visual impairments.

© 2025 The Author(s). Journal of Intellectual Disability Research published by MENCAP and John Wiley & Sons Ltd.

背景： 听力和视力障碍在唐氏综合症（DS）患者中很常见，然而目前尚不清楚感觉障碍是否与认知和行为功能如语言、记忆和社会交往有关。本文献综述旨在探讨这些关联。

方法： 对四个数据库进行了范围性回顾，以研究唐氏综合症患者中感觉障碍与认知或行为结果之间的联系。根据设计、样本量、评估方式和统计显著性对研究证据进行评价。

结果： 在筛选的1471项研究中，有38项符合纳入标准。听力障碍与婴儿期语言和运动发展延迟、童年时期整体认知能力较低和社会沟通困难以及成年期适应性功能降低和智力下降有关。视力障碍则与儿童时期的学业困难及成人期适应行为、视动整合能力和认知表现的下降相关联。成人的记忆、推理或处理速度等认知功能子域未被报道。

结论： 唐氏综合症患者未经矫正的听力和视力障碍与一生中的多种认知和行为结果有关。婴儿期和儿童时期，最强烈的关联是听力障碍与语言发展延迟之间的关系；而在儿童及成年时期则是视力障碍与适应性行为挑战的关系。感觉障碍似乎在类似领域——尤其是语言、适应性功能和学习方面，在整个生命周期中都存在挑战。这表明这些联系可能随着时间的推移持续存在，长期未经矫正的感觉障碍可能导致认知储备减少，并增加衰退的风险——强调了早期识别和干预的重要性。

关键词： 行为功能；认知功能；唐氏综合症；听力障碍；范围性回顾；视力障碍。

© 2025 The Author(s). Journal of Intellectual Disability Research published by MENCAP and John Wiley & Sons Ltd.