Visual filtering in time and space among persons with Down syndrome

Abstract

Background Individuals with Down syndrome (DS) appear to perform at a level that is commensurate with developmental expectations on simple tasks of selective attention. In this study, we examine how their selective attention is impacted by target changes that unfold over both time and space. This increased complexity reflects an attempt at greater ecological validity in an experimental task, as a steppingstone for better understanding attention among persons with DS in real-world environments. Methods A modified flanker task was used to assess visual temporal and spatial filtering among persons with DS (n = 14) and typically developing individuals (n = 14) matched on non-verbal mental age (mental age = 8.5 years). Experimental conditions included varying the stimulus onset asynchronies between the onset of the target and flankers, the distances between the target and flankers, and the similarity of the target and flankers. ResultsBoth the participants with DS and the typically developing participants showed slower reaction times and lower accuracy rates when the flankers appeared closer in time and/or space to the target. Conclusion No group differences were found on a broad level, but the findings suggest that dynamic stimuli may be processed differently by those with DS. Implications of the findings are discussed in relation to the developmental approach to intellectual disability originally articulated by Ed Zigler.

Mental age and intellectual disability: Psychologists' perspectives on the use of the term ‘mental age’ as it relates to adults with an intellectual disability

“…There are potential implications for translational research. Mental age is used in ‘basic’ intellectual disability research (e.g., Matsuba et al, 2023; Russo et al, 2021). In this context it is decoupled from applied settings and from a human rights lens.…”

“…Notwithstanding these developments, mental age descriptors are still in use in the literature, both clinically and in research contexts. For example, in studies of intellectual disability, it is not uncommon for adults with intellectual disability to be compared to typically developing children, who are matched on the basis of mental age (Angulo‐Chavira et al, 2022; Matsuba et al, 2023; Spaniol & Danielsson, 2022). Russo et al (2021) considered mental age matching in intellectual disability research as a tool for ensuring methodological rigour.…”