Aphasia researchers from Lingraphica, Vanderbilt University, and Nevada State College have collaborated on a study of factors affecting the therapeutic engagement decisions and success patterns of a person with moderate Broca’s aphasia and severe apraxia of speech engaged in autonomous practice of stimulated word repetition. The researchers were interested in particular in:  effects of differing conversational word frequencies of stimuli;  effects of differing typicalities of the three phonological constituents comprising stimuli; and  effects of two contrasting human-computer interaction designs for displaying multimodal responses to icon clicks.
The subject was a 62-year-old, monolingual English-speaking female who presented with moderate, chronic Broca’s aphasia and severe apraxia of speech 4 years after an ischemic left-hemisphere stroke. The practice words comprised 2 comparable sets of nine monosyllabic nouns, drawn from the Philadelphia Naming Test, each set associated with one of the two computer interaction designs. During autonomous practice, the subject was instructed to click on an icon as often as desired, focusing on the dynamic multimodal responses to those clicks, in preparation to produce the target word orally, and then verbally to say the target word computer support. All practice behaviors were recorded for later generation of detailed transcriptions that supported performance analysis.
Data analysis revealed three findings worthy of note in this subject. First, production success rates of consonantal onsets and vocalic nuclei were positively and significantly correlated with typicality values of those constituents, when an enlarged static drawing was displayed following user activation, but not when articulation videos were displayed. In effect, it appears that articulation videos are more potent than drawings in helping overcome weak practice effects from the relative under-rehearsal of low-typicality consonantal onsets. Second, when consonantal onsets were successfully produced, they initiated successful production of entire monosyllables 90% of the time when videos were used as stimuli, but only 55% of the time when static drawings used instead. And finally, practice engagement rose noticeably when the target words were of high conversational frequency but started with consonantal onsets of low typicality. The subject appeared motivated to master targets of this type, taking more time and more practice turns before moving on. Such findings may facilitate the personalized development of adaptive algorithms for autonomously used apps.
For further reading: R. D. Steele, M. de Riesthal, A. L. Ball. 2023. Design considerations for aphasia rehabilitation technologies: How linguistic factors and computer interaction designs alter user behaviors during autonomous practice. Assistive Technology Outcomes and Benefits. 17(1): 110-124. https://www.atia.org/atob-volume-17/