Implicit Motor Learning Strategies Benefit Dual-Task Performance in Patients with Stroke

Abstract

Background and Objectives: In stroke rehabilitation, the use of either implicit or explicit learning as a motor learning approach during dual tasks is common, but it is unclear which strategy is more beneficial. This study aims to determine the benefits of implicit versus explicit motor learning approaches in patients with stroke. Materials and Methods: Seventeen patients with stroke and 21 control participants were included. Motor learning was evaluated using the Serial Reaction Time Task (SRTT) in the context of dual-task conditions. The SRTT was conducted on two separate days: one day for implicit learning conditions and the other day for explicit learning conditions. Under the explicit learning conditions, a task rule was given to the participants before they started the task, but not under the implicit learning conditions. Learning scores were calculated for both implicit and explicit learning, and these scores were then compared within groups for patients with stroke and controls. We calculated the difference in learning scores between implicit and explicit learning and conducted a correlation analysis with the Trail Making Test (TMT) Parts A and B. Results: Learning scores on the SRTT were not different between implicit and explicit learning in controls but were significantly greater in patients with stroke for implicit learning than for explicit learning. The difference in learning scores between implicit and explicit learning in patients with stroke was correlated with TMT-A and showed a correlation trend with TMT-B. Conclusions: Implicit learning approaches may be effective in the acquisition of motor skills with dual-task demands in post-stroke patients with deficits in attention and working memory.

Keywords: attention; dual-task; explicit learning; implicit learning; motor skills; rehabilitation; serial reaction time; stroke; working memory.

Figure 1

Experimental protocol of implicit learning and explicit learning using the serial reaction time task. Each learning protocol consisted of a practice block, a learning phase (Blocks 1–5), and a random block (Block 6). Sequence A, 1–3–4–2–3–2, and sequence B, 3–1–2–4–1–4, were used in implicit and explicit learning, respectively.

Figure 2

Results for the serial reaction time task. * indicates a significant difference between implicit learning and explicit learning (p < 0.05). Stroke, patients with stroke; Control, healthy participants.