• David Laird Zimmerman David Laird Zimmerman

Autism Spectrum Disorder (ASD) is a neurodevelopmental condition that is characterised by deficits in social interaction and communication as well as restricted behaviours or interests (American Psychiatric Association, 2013). Commonly referred to as high-functioning, adults with ASD with no co-occurring intellectual disability present with heterogeneous ASD characteristics and psychosocial profiles. While some individuals value specific characteristics associated with a diagnosis of ASD, others report feeling isolated and rejected by society. However, there is currently a poor understanding of the factors that account for variations in psychosocial outcomes, conceptualised in this research as mental health and social and adaptive functioning. Comprised of four main studies, the broad objective of this thesis was to advance understanding of factors influencing the psychosocial outcomes for this population. Study 1 employed systematic review methodology to identify quantitative studies investigating factors associated with psychosocial outcomes for high-functioning adults with ASD. The findings of 27 studies published between 1989 and 2015 (N = 1398; M age = 28.54 years; 71.6% males) were qualitatively synthesised. The factors most consistently related to poorer psychosocial outcomes included: greater ASD symptom severity, lower childhood IQ, impaired non-verbal learning and cognitive shifting deficits. There was also preliminary support concerning associations between negative thinking styles, maladaptive coping, perceptions of low social support and poor mental health. Key gaps in the literature related to understanding the impact of higher-order cognitive abilities (i.e., cold and hot executive functions) and personal and social resources on psychosocial outcomes.