Background: Movement sonification, the use of real-time auditory feedback linked to movement parameters, have been proposed to support rehabilitation. Nevertheless, if promising results have been reported, the effect of the type of sound used has not been studied systematically, and mechanisms involved during movement execution with sonification remain poorly understood. The aim of this study was to investigate in a single session the effect of different types of sonification both quantitatively and qualitatively on patients with acquired brain lesions and healthy participants. This experiment should be considered as a first step before establishing a longitudinal clinical rehabilitation study.
Methods: An experimental setup enabling arm sonification was developed using three different categories of sonification (direct sound modulation, musical interaction, and soundscape). Simple moving forward movements performed while sliding on a table with both arms were investigated with all participants. Quantitative analysis on the movement timing were performed, and different comparisons were processed (sound / no sound, affected arm / less affected arm, category and type of sonification). Qualitative analysis of semi-structured interviews were also conducted, as well as neuropsychological evaluation of music perception.
Results: For both the patient and healthy groups (15 participants each), average duration for performing the arm movement is significantly longer with sonification compared to the no-sound condition (p<10-3). Differences were also observed between the sound categories in the case of the paretic arms of patients and the dominant arms of healthy participants (p<0.05). Qualitative analysis of semi-structured interviews revealed the motivational and affective aspects of each type of sonification. Most participants of both groups preferred to complete the task with sound, and more precisely with one that uses sound of nature environment (soundscape).
Conclusion: Overall, our results confirm that the sonification has an effect on the temporal execution of the movement during a single-session. This effect is variable among participants, which requires further studies to better understand. Globally, sonification is welcomed by the participants, and we found convergent and differentiated appreciations of the different sonification types. This enables us to provide researchers with recommendations for clinical studies for personalized music-guided rehabilitation.