Do People With Apraxia of Speech and Aphasia Improve or Worsen Across Repeated Sequential Word Trials?

During motor speech examinations for suspected apraxia of speech (AOS), clients are routinely asked to repeat words several times sequentially. The purpose of this study was to understand the task in terms of the relationship among consecutive attempts. We asked to what extent phonemic accuracy changes across trials and whether the change is predicted by AOS diagnosis and sound production severity.

One hundred thirty-three participants were assigned to four diagnostic groups based on quantitative metrics (aphasia plus AOS, aphasia-only, and aphasia with two borderline speech profiles). Each participant produced four multisyllabic words 5 times consecutively. These productions were audio-recorded and transcribed phonetically and then summarized as the proportion of target phonemes that was produced accurately. Nonparametric statistics were used to analyze percent change in accuracy from the first to the last production based on diagnostic group and a broad measure of speech sound accuracy.

Accuracy on the repeated words deteriorated across trials for all groups, showing reduced accuracy from the first to the last repetition for 62% of participants. Although diagnostic groups differed on the broad measure of speech sound accuracy, severity classification based on this measure did not determine degree of deterioration on the repeated words task.

Responding to a request to say multisyllabic words 5 times sequentially is challenging for people with aphasia with and without AOS, and as such, performance is prone to errors even with mild impairment. For most, the task does not encourage self-correction. Instead, it promotes errors, regardless of diagnosis, and is, therefore, useful for screening purposes.