Adaptive functioning and functional reading skills in Williams syndrome

This thesis investigated adaptive functioning or everyday living skills in Williams syndrome (WS) and considered the relationship between adaptive functioning with demographic and environment variables and functional reading skills. WS is a genetic disorder, resulting from a microdeletion on chromosome 7, with a prevalence of approximately 1 in 7,500 births. There are characteristic physical and behavioural features of WS and the intellectual and cognitive profile of the disorder has been studied extensively due to interesting peaks and valleys of ability. Less well understood is the profile of adaptive functioning in WS and the profile of reading abilities. This thesis comprises of a general introduction, three chapters and a conclusion. The introduction explains the conceptual links between the three main chapters from a design and research perspective. Chapter One is a systematic review of adaptive functioning in WS and includes 15 published studies and 3 Ph.D dissertations. The relationship between adaptive skills and demographic variables such as age, gender and intellect were considered. The review found the overall level of adaptive functioning to be low in WS; however, there was evidence of age related changes with adults demonstrating comparatively lower skills when compared to children and adolescents. Also, the pattern of relative strengths and weaknesses was different across these age spans. Methodological evaluation found that further research into adaptive functioning was warranted in WS, with updated assessment tools, further investigation of age-related differences, along with the inclusion of environmental factors which may contribute to adaptive functioning. The second chapter follows on from this review, with an empirical study that aimed to investigate adaptive functioning in WS across the age range of children through to adults using an up-to-date measure of adaptive functioning. Environmental contributions to adaptive functioning were also explored. Thirty individuals with a genetically confirmed diagnosis of WS, all with the common ~1.6Mb deletion participated in the study. Global adaptive functioning was considered, as were domain and subdomain scores. Group averages were explored, as well as individual profiles of strength and weakness. The study revealed significant variability in adaptive abilities, and while neither gender nor intellectual functioning were found to be related to adaptive functioning, chronological age and some aspects of the family environment were found to significantly relate to adaptive abilities. The third chapter investigated functional literacy abilities in WS to consider whether reading abilities were found to be related to adaptive functioning, in particular, independence in daily activities, such as telling the time, managing money, job skills etc. A cognitive neuropsychological approach was used to examine lexical and nonlexical reading abilities in WS to determine whether there was any evidence of different reading patterns, along with cognitive and intellectual correlates of reading. Reading was found to be significantly related to adaptive abilities. Findings highlighted the importance of appropriate and ongoing reading instruction for people with WS, including children and adults. The thesis provides evidence that an understanding of adaptive abilities in special populations such as WS is critical, not only for diagnostic purposes, but also to assist with planning appropriate educational, vocational and recreational opportunities and support for these individuals and their caregivers, to promote independence. A particularly strong message of the findings from this thesis is that adults with WS require ongoing efforts to ensure an enriched environment that leads to further opportunities for further education, social interaction, routine and personal growth.