RESUMO
Several models of anxiety in autistic adults have focused on the role of intolerance of uncertainty which has biological and evolutionary bases, as a cognitive explanation for the high prevalence of anxiety in autism. This framework suggests that all people are born with a healthy level of intolerance of uncertainty, and as we develop, this intolerance is lessened as we learn when situations are safe and begin to understand and manage the uncertainty. This process of learning about managing uncertainty does not happen in the same way in those who are high in autistic traits, which could be the reason for the high levels of anxiety symptoms commonly seen in this population. We examined archival data of 199 non-autistic and 55 autistic adults from prior studies in which we collected self-report measures of autistic traits, intolerance of uncertainty, sensory processing, and anxiety. We conducted two path analyses to examine the role of intolerance of uncertainty in anxiety in autistic adults. The first model tested the idea that intolerance of uncertainty, an evolutionary phenomenon common for all people, could explain some of the cognitive aspects of anxiety in autism. The second model suggests that primary neurodevelopmental differences associated with autistic traits underlie the sensory sensitivity and sensory seeking behaviors, which in turn increase intolerance of uncertainty and subsequent anxiety. We found that the "neurodevelopmental" model had better model fit than the "evolutionary stress" model, suggesting that the neurodevelopmental impact of higher levels of autistic traits could moderate a non-autistic trajectory of learning to manage uncertainty as children develop and understand that uncertainty is common and acceptable.
RESUMO
Anxiety is the most significant mental health concern for both Williams syndrome (WS) and autism. Whilst WS and autism are characterized by some syndrome-specific social differences, less is known about cross-syndrome profiles of anxiety symptoms. Previous research has shown that Intolerance of Uncertainty (IU) is a core mechanism of anxiety maintenance for clinically anxious populations and for autistic children, adolescents, and adults. The only published study in this area for WS has shown some similar patterns-with an added emphasis on the role of sensory sensitivities-in a sample of older teens and adults (mean age = 24), with the authors highlighting the need for younger samples to consider developmental influences. Here we report a cross-syndrome, cross-sectional mediation analyses of children diagnosed with WS or autism, including data from parent surveys of 90 children with WS (n = 48) or autism (n = 42). Group differences showed higher trait levels on all measures for the autism group. Importantly, the relationship between social profile and anxiety was fully mediated by IU level for both groups. This suggests possible similar core mechanisms underlying anxiety in these conditions, and the possibility of generalized intervention approaches especially related to managing distress related to uncertainty in multiple contexts. LAY SUMMARY: Autism and Williams Syndrome share some similarities in social profile and also in anxiety traits, but there are also some key differences as well. Comparing them side-by-side at the same time improved identification of ways to reduce feelings of anxiety. We found that the intolerance of uncertainty affected the relationship between social profile and anxiety in the same way for young children diagnosed with autism or Williams syndrome, meaning that intervention approaches could be similar for both.