This clinical focus article describes an exploratory case study addressing reduction of vocal loudness in a young adult with a history of autism spectrum disorder and developmental delay. The need for a short-term pullout individual intervention arose from his participation in the Advancing Language and Literacy group, a program that provides support for enhancement of speech, language, and literacy skills for young adults with developmental disabilities.


The participant attended individual treatment sessions weekly for 9 sessions, all of which were digitally audio-recorded. Client awareness of different loudness levels was first established using nonspeech sounds and speech samples. Loudness in spontaneous speech was monitored with support of verbal and visual feedback in the individual sessions and tracked in individual sessions as well as sessions of the Advancing Language and Literacy group, which served as a generalization context.


In the individual sessions, the participant's spontaneous production of acceptable volume improved from 42% to 92% of utterances. Observation of group participation indicated generalization, with the majority of utterances produced posttreatment at an acceptable volume.


This clinical focus article emphasizes suprasegmental aspects as a dimension of communicative competence and highlights the need for continued intervention research and services for young adults with developmental disabilities.


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