Characterizing restricted and unusual interests in autistic youth

Abstract

A broad range of interests characterized by unusual content and/or intensity, labeled as circumscribed interests (CI), are a core diagnostic feature of autism. Recent evidence suggests that a distinction can be drawn between interests that, although characterized by unusually high intensity and/or inflexibility, are otherwise common in terms of their content (e.g., an interest in movies or animals), labeled as restricted interests (RI), and interests that are generally not salient outside of autism (e.g., an interest in traffic lights or categorization), labeled as unusual interests (UI). The current study aimed to further characterize RI and UI by exploring their association with age, sex, IQ, and social motivation, as well as to examine differences in the adaptive benefits and negative impacts of these two subdomains. Parents of 1892 autistic children and adolescents (M age = 10.82, SD age = 4.14; 420 females) completed an online survey including the Dimensional Assessment of Restricted and Repetitive Behaviors and the Social Communication Questionnaire. Both RI and UI were found to be highly frequent. Sex-based differences were observed in the content, but not intensity, of CI such that females were more likely to show interests with a social component. Finally, RI and UI showed distinct patterns of association with age, sex, IQ, and social motivation, as well as metrics of adaptive benefits and negative impacts. Findings afford a more nuanced understanding of sex-based differences in CI and, crucially, provide preliminary evidence that RI and UI represent distinct constructs that should be studied independently in future research.

Profiles of circumscribed interests in autistic youth

“…Finally, the three profiles demonstrated different sex compositions with males significantly more likely to be in the low CI profile and females significantly more likely to be in the predominantly RI profile. Although it is difficult to situate findings in the context of previous literature as this is the first study to capture subgroups based on CI patterns, that males were more likely to be in the low CI profile is somewhat inconsistent with previous studies that have reported no sex-based differences in the intensity of CI (Anthony et al, 2013;Sutherland et al, 2017;Spackman et al, 2022b). However, the finding that females were more likely than males to be in the Predominantly RI profile, is broadly consistent with previous literature that suggests the interests of autistic females more closely align with the interests of neurotypical females than autistic males (Harrop et al, 2018;Bourson and Prevost, 2022).…”

“…However, the finding that females were more likely than males to be in the Predominantly RI profile, is broadly consistent with previous literature that suggests the interests of autistic females more closely align with the interests of neurotypical females than autistic males (Harrop et al, 2018;Bourson and Prevost, 2022). Further, by identifying a profile of interests, mostly consisting of RI, that females are more likely to display, this study builds on previous group-level findings using the DARB that reported several specific RI items were more commonly endorsed by females than males-including having a favorite person or an interest in music, art, literature, and psychology (Spackman et al, 2022b). In summary, the use of person-centered analysis in the current study has identified clusters of participants that were further differentiated by key demographic, cognitive, and clinical validators, thus providing important, albeit preliminary, evidence that different profiles of CI presentations may be underpinned by distinct cognitive mechanisms.…”

“…Previous studies suggest that upwards of 75% of autistic youth experience CI and that presentations of these behaviors vary significantly across individuals (Klin et al, 2007 ; Anthony et al, 2013 ; Uljarević et al, 2021a ; Spackman et al, 2022b ). Using an informant-report measure of CI, Anthony et al ( 2013 ) observed that autistic youth displayed an average of 11–15 CI, with the most common interests in autistic boys being video games and Lego and the most common interests in autistic girls being math and music.…”

“…The literature to date has reported largely inconsistent findings regarding the relationship between CI and key correlates such as age, sex, IQ, language level, social abilities, and anxiety (South et al, 2005 ; Klin et al, 2007 ; Turner-Brown et al, 2011 ; Anthony et al, 2013 ; Frazier et al, 2014 ; Sutherland et al, 2017 ; Uljarević et al, 2021a , c ; Spackman et al, 2022b ). This inconsistency may be in large part due to the fact that the majority of previous studies have operationalized CI as a unidimensional domain.…”