Functional neuroplasticity in chronic post-stroke aphasia following a singing intervention in a cross-over randomised trial

Group-based singing has been shown to improve language outcomes and induce structural neuroplasticity in chronic post-stroke aphasia (PSA). However, the functional neuroplasticity changes induced by such interventions remain unknown. Here our main aim was to determine these changes using a cross-over randomised trial. Nineteen patients with PSA were randomly allocated to a 4-month multicomponent singing-based intervention (singing group) or standard care (control group). With a pre-post design, we pooled data from both groups and analysed verbal learning and task-based fMRI activation of two novel songs (trained or untrained during intervention) at two time points (pre- and post-intervention). Post-intervention, patients with PSA produced more correct syllables from the trained song and for the trained relative to the untrained song. fMRI results revealed increased activation when singing along to the trained song in the right postcentral gyrus, and in the right posterior superior temporal gyrus (pSTG) when singing along to the trained vs. untrained song. Notably, right pSTG activation increases correlated with improved naming abilities. Collectively, these findings indicate that group-based singing is associated with verbal learning and induces functional neuroplasticity changes in the singing network, derived from demographically matched healthy controls, which are associated to improved naming abilities in chronic PSA. https://www.clinicaltrials.gov, Unique identifier: NCT03501797.