Rubinstein-tayi syndrome: from behaviour to cognition

Examination of Autism Spectrum Disorder (ASD) phenomenology in genetic syndromes can aid our understanding of the aetiological pathways underpinning ASD. The current thesis directed attention to the specific study of Theory of Mind (ToM) development in syndrome groups with a high prevalence of ASD but fractionated social profiles. In an initial group comparison study, Rubinstein-Taybi syndrome (RTS) was highlighted as a syndrome group of interest. When compared to Down syndrome (DS), Fragile X syndrome (FXS) and idiopathic ASD, RTS showed a comparatively high prevalence of ASD but a fractionated ‘sociable’ social profile. As traditional ToM tasks load heavily on cognitive processes they are unsuitable for some individuals with intellectual disability. Consequently, a scaled battery of ToM ‘precursor’ tasks was constructed and validated using a normative sample. This scale was then applied, alongside Wellman and Liu’s (2004) ToM scale, to examine the development of ToM in RTS. An analysis of overall ability indicated that RTS may evidence relatively ‘spared’ early social cognitive skills. However, later ToM skills may be delayed due to memory difficulties. Developmental trajectory analysis indicated that RTS followed a different developmental sequence to the normative sample. Gaze understanding was found to be significantly harder than expected. These findings are discussed in relation to their theoretical implications for models of ToM and ASD, clinical implications for individuals with RTS, and potential areas for future study