Augmenting behavioural activation with mental imagery improves post-stroke depressive symptoms

Depression affects approximately 30% of stroke survivors. Behavioural activation (BA) is a depression intervention based on completing positively reinforcing activities. However, post-stroke cognitive changes, like episodic memory difficulties, could affect encoding, storing, and recollecting reinforcing activities. Mental imagery has high acceptability in post-stroke motor recovery interventions, and in depression and anxiety interventions outside of stroke. We evaluated whether augmenting BA with mental imagery improves mood and activity outcomes in stroke compared to BA alone. Randomized participants received positive activity scheduling ("standard" BA) with (1) mental imagery simulating the planned activity, or (2) an imagery active control unrelated to the planned activity. Depressive symptoms and activity measures were completed weekly over 3 sessions and between-group differences evaluated via mixed-effects modelling. Exploratory models covaried for baseline verbal episodic memory and subjective memory. N = 45 participants [M age = 69.29, M years post-stroke = 3.00, 60% male] took part. BA with mental imagery led to significantly greater reduction in depressive symptoms compared to standard BA (t₍79₎= -2.72, p = .008; Cohen's d = 0.65). Subjective, but not objective, memory correlated with depression severity and activity engagement. There were no between-group differences in activity measures. Mental imagery may enhance mood outcomes in BA post-stroke, potentially supporting positive activity reflections irrespective of activity completion.