Parsing the heterogeneity of social motivation in autism

BackgroundSocial motivation is posited as a key factor in the expression of the autism phenotype. However, lack of precision in both conceptualization and measurement has impeded a thorough understanding of its diverse presentation and associated outcomes. This study addresses this gap by identifying subgroups of autism characterized by deficits in distinct facets of social motivation, relative to normative benchmarks.MethodsData were from 509 participants with autism, aged 5-to-21 years (M = 10.43, SD = 3.67; 81% male), enrolled in the Healthy Brain Network. Latent profile analysis was employed to identify subgroups characterized by unique configurations of reticence, seeking, and maintaining facets of social motivation, derived from a comprehensive multi-instrument factor analysis of symptom and screening measures. Pearson's chi-square tests and one-way analysis of variance were performed to explore subgroup differences in demographic characteristics, cognitive abilities, co-occurring psychopathologies, and other aspects of social functioning.ResultsFour distinct subgroups were identified: Engaged (n = 247), exhibiting the fewest challenges across each area; Inhibited (n = 143), characterized by high reticence, mild challenges in seeking, and few challenges in maintaining; Aloof (n = 68), characterized by challenges with seeking and maintaining but relatively low reticence; and Avoidant (n = 52), characterized by the highest challenges across all areas. Subgroups did not differ in terms of chronological age or sex. The Engaged subgroup exhibited the fewest challenges in other aspects of social functioning and co-occurring psychopathologies, while the Avoidant subgroup exhibited the greatest challenges, and with the Inhibited and Aloof profiles falling in between.ConclusionsThis study highlights the heterogeneous nature of deficits in social motivation in autism relative to normative benchmarks, suggesting potential avenues for tailored interventions aimed at addressing the specific challenges experienced by individuals within each subgroup. Nevertheless, there remains a need to develop more refined measurement tools capable of capturing even finer-grained aspects and diverse expressions of social motivation, facilitating further characterization of individual differences across diagnostic boundaries.