A Longitudinal Case Study: Language Abilities of Minority Autistic Young Adults

Abstract

One aim in clinical research is furthering understanding of linguistic variation across populations. While important for understanding language acquisition in the context of human development, little is known about the language abilities of autistic adolescents and young adults, especially those who are racial/ethnic minorities or whose language is below typical. These knowledge gaps limit our understanding of the experiences of autistic individuals. To address these gaps, a longitudinal case study investigated the language abilities of eleven autistic minority young adults (1 female, 10 males; 17 – 23 years). Specifically, it explored: (a) whether individuals changed in relative performance levels within the group across three years; (b) whether speech sound disorder interfered with language assessment; (c) individual differences in expressive language and receptive language; (d) individual differences in expressive and receptive vocabulary; (e) individual differences in use of finiteness markers and judgments of finiteness errors. The author administered standardized tests online on overall language, vocabulary, morphosyntax, nonverbal intelligence, and nonword repetition. Analysis included descriptives and nonparametric statistics. Results revealed that participants did not change in relative performance levels and had articulation such that speech sound disorder likely did not interfere with assessment performance. Most participants performed near floor on standardized assessments of overall language and vocabulary, with limited individual receptive-expressive differences. Participants varied in their use of finiteness markers and judgments of morphosyntax. This study adds longitudinal knowledge on the language abilities of autistic adolescents and young adults. Findings support longitudinal consistency of language assessment outcomes in this age range, such that participants had persistent language impairment.