Language acquisition after mutism: a longitudinal case study of autism.

This longitudinal case study challenges the assumption that individuals with autism who have severely restricted speech and language skills have a poor prognosis for further development of expressive oral language. The study follows the development of a woman with autism from mutism at age 10 to acquisition of a range of spoken and written language skills at age 26. The intervention in which the woman participated and her skills pre- and post-intervention and at two follow-up assessments are documented. The results support the hypotheses that speech and language development may proceed after mutism associated with limited verbal imitation and phoneme production skills, that some skills may plateau or decline, and that both spoken and written language may become viable forms of communication.