Your Mileage May Vary: Individuals with Primary Progressive Aphasia Differ Widely in Their Utilization of Congruent...

Background/Objectives: Primary progressive aphasia (PPA) is a clinical syndrome associated with gradual language impairment caused by neurodegenerative disease. While people with post-stroke aphasia often depend on visual and prosodic cues to facilitate language, we hypothesized that people with PPA may have difficulty using such cues due to degeneration in the right hemisphere (albeit less than in the left hemisphere) in PPA. Methods: Eighty-eight outpatients diagnosed with PPA received the Hopkins Auditory Comprehension with Context Assessment (HACCA), a recently developed instrument that systematically titrates both acoustic (prosody) and visual (speaker image) cues in a four-item forced-choice sentence picture matching paradigm assessing comprehension. Patients were grouped based on the effects of cues on accuracy and were examined both by the PPA variant and individually. Results: There was a significant difference between performance classifications across the three cueing conditions as a function of PPA variant (p = 0.014). When individuals with distinct complementary profiles of performance across conditions were examined separately, a small number with logopenic PPA uniquely benefitted from the inclusion of video, while certain patients performed more poorly given any additional cues. HACCA performance across cueing conditions had a strong positive association with other concurrent measures of communication and cognition. Conclusions: Individual patterns of response to prosodic and visual cues provide important insights valuable in refining therapeutic approaches that target the retention of function and support a more robust understanding of the individual variability among patients with this uncommon neurodegenerative syndrome.