The impact of contextual, conversational, and affective factors on a child's speech intelligibility

The categorization and treatment of speech output problems traditionally focuses on the segmental aspects of a client's speech. There tends to be less emphasis on speech sounds in use in different communicative tasks, and the enactment of different interactional roles by speech clients and clinicians. This paper presents an in-depth discussion of interactional data gathered from speech therapy sessions involving a five year old client diagnosed with an articulation impairment, and his speech clinician. A prominent, and initially puzzling, characteristic of the client's speech were marked fluctuations in articulatory accuracy, and intelligibility. Our inquiry draws on principles and tools from Conversation Analysis, Systemic Functional Linguistics, Grounded Theory, and the notion of informativity. In addition, we employ detailed narrow phonetic transcription of the client's speech data. Analysis involved repeated, theory-driven data sampling. Informativity, linked to different interactional registers within the therapy session, emerged as a key explanatory factor in the intelligibility fluctuations of the client's speech output. Implications include that combining detailed phonetic and interactional analyses can provide valuable insights into how clients understand and construct the assessment and therapy process, and in turn these insights can assist in planning and executing maximally productive intervention.