Slide Slam D7
Quantitative assessment of pitch and rhythm production abilities in left hemisphere stroke survivors with and without aphasia: evidence for shared rhythm resources for speech and music
Alexis Basciano1, Corianne Rogalsky1, Ayoub Daliri1, Arianna LaCroix2, Brandon Gray1, Mallory Wojtaszek1, Saahithi Mallapragada1; 1Arizona State University, 2Midwestern University
Previous studies indicate that individuals with aphasia also may have difficulties with rhythm perception in music, suggesting a possible overlap of critical neural resources between speech and music perception for rhythm in the left hemisphere. However, there are comparatively few studies of music production or musical auditory-motor integration in individuals with aphasia, in part because objectively assessing the pitch and rhythmic abilities of individuals with post-stroke aphasia is difficult given the subjective nature of music ratings and the variety of possible error types. Thus, the purpose of the current study was: (1) to develop a quantitative, sensitive method of evaluating music repetition abilities in stroke survivors with aphasia and (2) to use this method to determine how music repetition accuracy in stroke survivors is related to their performance in speech auditory-motor tasks. Twenty-three chronic left-hemisphere stroke survivors with and without aphasia completed a music repetition task, and tasks known to engage speech auditory-motor integration (non-word repetition, verbal working memory span, difficult sentence comprehension). The music repetition task consisted of 10 novel piano melodies (five to eight piano notes long) presented three time each. Participants were asked to listen to each melody and then sing the melody. Praat software was used to extract fundamental frequency and duration of each note in each melody produced. We then calculated a correlation between fundamental frequencies of notes of the produced melody with those of the played target melody (i.e., a pitch score). We used a similar procedure to calculate a correlation between produced duration and the target duration (i.e., a rhythm score). As expected in a heterogenous sample of stroke survivors, there was considerable variability in performance on the music repetition task across the sample, but neither the length of the melody nor the repetition number significantly affected performance. Age and lesion size also were not significantly correlated with pitch or rhythm performance. Nonword repetition was significantly correlated with both rhythm (p=0.05) and pitch (p=0.04) performance. Rhythm accuracy, but not pitch accuracy, significantly correlated with working memory span performance (p=0.01) and approached significance with sentence comprehension performance (p=0.06). A larger sample of stroke survivors and a control group are needed to further investigate these relationships, but these initial results suggest that we have developed an effective method to objectively evaluate music repetition abilities in left hemisphere stroke survivors with and without aphasia. Our findings also suggest that a stroke survivor’s music repetition performance may be related to speech auditory-motor integration abilities (known to be engaged in speech repetition, verbal working memory, and sentence processing) via shared neural resources in the left hemisphere supporting sensorimotor integration of rhythm in both domains.