Dissociation of Cross-Sectional Trajectories for Verbal and Visuo Spatial Working Memory Development in Rubinstein Taybi syndrome.

Abstract

Background. Impairments in working memory (WM) might amplify behavioural difference in genetic syndromes associated with intellectual disability (ID) and account for variability in behavioural phenotypes. Murine models of the genetic disorder Rubinstein-Taybi syndrome (RTS) evidence memory impairments but there is limited research on memory in this syndrome. We examine the cross-sectional trajectory of domains of WM development in RTS. Methods. Individuals with RTS (N = 32) and typically developing (TD) children (N = 89) completed a battery of WM tasks. Participants with RTS also completed an IQ assessment and parent/carers completed the Vineland Adaptive Behavior Scales (VABS). A crosssectional trajectory analysis was conducted. Results. The RTS group showed significant WM deficits relative to mental age on measures of WM span in both verbal and visuo-spatial domains. However, whilst better performance on verbal WM span tasks was positively correlated with higher mental age in RTS, this association was not observed on the visuo-spatial span task despite being evident in the TD comparison group. Conclusions. Individuals with RTS are likely to have difficulties with tasks that rely on WM, above and beyond difficulties predicted by overall ability. In addition, there is a dissociation between the cross-sectional trajectories for verbal and visuo-spatial skills in RTS. Interventions and education strategies for individuals with RTS may need to be tailored to reduce or accommodate these difficulties.