# Enhanced motor recovery in stroke patients through dual-modal intervention: motor imagery and task-oriented robot training

## TL;DR

Combining motor imagery with robot-assisted training improves lower limb movement and brain connectivity in stroke patients.

## Contribution

This study is the first to show that combining motor imagery with robotic training enhances motor recovery and brain connectivity in stroke patients.

## Key findings

- The experimental group showed significant improvements in FMA-LE and BBS scores compared to the control group.
- Both groups improved gait parameters like step frequency and gait speed after intervention.
- Enhanced functional connectivity between the prefrontal cortex and motor regions was observed in the experimental group.

## Abstract

Motor imagery (MI) has garnered significant interest as a novel rehabilitation method for stroke. Additionally, task-oriented robot training has been shown to enhance lower limb motor function in patients with early-stage stroke. However, the therapeutic effects of combining these two approaches remain unclear, and the underlying mechanisms are not yet understood. This study aims to investigate the effects of MI combined with task-oriented robot training on the lower limb motor function of post-stroke patients.

First-ever stroke patients meeting the inclusion criteria were recruited and randomly allocated eligible participants to the control group (n = 91) or the experimental group (n = 91). Based on routine conventional physical therapy, the experimental group received task-oriented robot training combined with MI training, whereas the control group received task-oriented robot training combined with muscle relaxation training. The outcome indicators are the Fugl-Meyer Assessment of Lower Extremity (FMA-LE), Berg Balance Scale (BBS), and spatio-temporal gait parameters, which reflect the patients’ lower limb motor function. The functional connectivity between regions is measured by functional near-infrared spectroscopy (fNIRS).

Significant improvements in FMA-LE and BBS were observed in the experimental group compared with the control group (p < 0.05). Although no significant differences were observed between groups post-treatment (p > 0.05), both groups demonstrated improved step frequency and gait speed scores and reduced gait cycle scores following intervention (p < 0.05). In addition, the experimental group showed significantly enhanced functional connectivity between the prefrontal cortex and motor-related regions compared to the control group (p < 0.05).

Combining MI training with task-oriented robotic training can enhance lower limb motor function and enhance the brain’s functional connectivity. Changes in functional connectivity within the prefrontal cortex (PFC) and motor-related cortex may serve as a potential therapeutic target for promoting motor recovery in stroke patients. Future studies should incorporate task-based functional Magnetic Resonance Imaging (fMRI) data to elucidate the directionality of information flow between these brain regions, thereby advancing our understanding of causal interactions underlying functional improvements in post-stroke gait rehabilitation.

Trial registration: It was retrospectively registered at the Chinese Clinical Trial Registry on 8 July 2025 (Registration No. ChiCTR2500105631).