Intelligibility in dysarthria: effects of listener familiarity and speaking condition.

This study examined the effects of familiarization and speaking condition on sentence intelligibility for a speaker with dysarthria secondary to a traumatic brain injury (TBI). Familiarization procedures included hearing the speaker read a paragraph or a word list comprised of a random ordering of the words in the paragraph. Such an approach allowed for statements concerning the benefit of prior exposure to a sentence-level prosody and word level articulatory-acoustic patterns versus only word-level articulatory-acoustic patterns. Following word list, paragraph, or no familiarization, listeners orthographically transcribed sentences in either a habitual, slow, fast, or loud condition. Listeners receiving either word list or paragraph familiarization accurately transcribed a higher percentage of words in sentences than listeners receiving no familiarization. Intelligibility scores did not differ for word list or paragraph familiarization, however. Listeners also were more accurate transcribing sentences produced in the loud condition compared to habitual and fast conditions. Clinical implications are discussed.