Abstract
Echolalia, the immediate or delayed repetition of speech, is a core diagnostic criterion for autism spectrum disorder. It has been studied for over 50 years and is well-described; however, no consensus on prevalence estimates exists for echolalia's occurrence in autistic youth. The current study sought to (1) describe endorsement of echolalia-related items using parent-, teacher-, and clinician-reports in a well-validated sample of autistic youth and (2) characterize relations between echolalia and other key factors, including age, language ability, and repetitive behaviors. Participants (n = 2555, 4-17 years, 13% female, 78% White) from the Simon Simplex Collection provided data from multi-informant ratings of echolalia and related behaviors. Nine parent-, clinician-, and teacher-report items were extracted from five measures to broadly capture echolalia through a composite score. Results indicated that as many as 90% of autistic individuals express echolalia at some point in their development. Hierarchical linear regression was conducted to evaluate relations between echolalia, verbal ability, and repetitive behaviors, controlling for age, sex, and autism severity. Results indicated the main effects of verbal ability and repetitive behaviors. A significant interaction qualified this main effect wherein age was negatively associated with echolalia for children with higher verbal ability, but not those with lower verbal ability, suggesting that adolescents with less generative speech may leverage echolalia as a communicative strategy. Echolalia was positively associated with repetitive behaviors across development. These associations support a dualistic interpretation of echolalia as functional communication and as a form of repetitive behavior. Future research is needed to understand the developmental trajectories of echolalia and develop affirming support for this autistic behavior.