Resting-state network plasticity induced by music therapy after traumatic brain injury

Traumatic brain injury (TBI) is characterized by a complex pattern of abnormalities in resting-state functional connectivity (rsFC), and neuropathology focused on network dysfunction. Here we report a fMRI study of brain network changes induced during a randomised controlled trial of neurological music therapy in 23 moderate/severe TBI patients. Our ROI-to- ROI approach used four networks as sources: the frontoparietal (FPN), dorsal attention (DAN), default mode (DMN), and salience (SAL) networks. These networks include high-degree nodes or network hubs, and have all been associated with cognitive impairment after TBI. Furthermore, we investigated the correlation between brain network changes and executive function (EF). Lastly, we implemented a seed-to-voxel analysis to cross-link whole-brain rsFC with brain morphometry results obtained in our previous study of this data. The neurological music therapy increased the coupling between the FPN and DAN as well as between these networks and primary sensory networks that were engaged during musical training. By contrast, the DMN was less connected with sensory networks after the intervention. Similarly, there was a shift towards a less connected state within the FPN and SAL networks, which are typically hyperconnected following TBI. Improvements in EF were correlated with rsFC within the FPN and between the DMN and sensorimotor networks. Finally, the increase in grey matter volume in frontal regions was associated with greater rsFC in areas implicated in music processing. This study is the largest of its kind, and suggests that rsFC in response to music-based rehabilitation may provide sensitive biomarkers of cognitive recovery after TBI.