Action Observation Training for Upper Limb Stroke Rehabilitation: A Pilot Study on the Role of Attention

Background: Restoring motor function is crucial for daily life after a stroke. Although patients' engagement and attention influence motor recovery, these factors are frequently overlooked in rehabilitation interventions. Methods: This prospective open-label pilot trial (NCT04622189) investigated the impact of attentional deficits on engagement and motor recovery in 10 subacute stroke patients undergoing a 4-week action observation training program. At baseline, they were divided into two subgroups based on attentional performance, as determined by scores on the Test of Attentional Performance (subtests of divided attention and Go/No-Go): those with attention deficits (AD, i.e., deficits in one or both tasks, n = 6) and those without (No_AD, no deficits in either task, n = 4). Results: Both groups exhibited similar motor profiles at baseline; however, the AD group presented significantly lower cognitive reserve (AD mean (SD) 92.2 ± 4.09, No_AD 120 ± 14.9, p = 0.005) and greater anxiety and depressive symptoms (AD 66.7%, No_AD 0%, p = 0.035). While all patients showed improvements in motor outcomes, the No_AD group demonstrated significantly greater gains in upper limb function, as assessed by the Fugl-Meyer Assessment (AD 3.33 ± 1.21, No_AD 10.8 ± 5.7, p = 0.013). Engagement and accuracy of interactive questions, used as proxies for concentration during training, were also higher in the No_AD group and positively correlated (rho = 0.9075, p ≤ 0.001). Moreover, patients with attention deficits reported lower levels of engagement during training. Conclusions: These findings indicate that attentional status may affect both adherence to and responsiveness to rehabilitation. This highlights a potentially relevant factor to consider when improving post-stroke interventions.