Effects of Motor Imagery Training Based on Near-Infrared Functional Brain Imaging on Upper Limb Function in Stroke...

This randomized controlled trial investigated the effects of motor imagery training (MIT) monitored by functional near-infrared spectroscopy (fNIRS) on upper limb motor function and cortical activation in stroke patients. Seventy participants were allocated to either an MI group, which received conventional rehabilitation therapy (CRT) supplemented with visual and kinesthetic-based MIT, or a control group (CON group), which received CRT alone. The CRT intervention consisted of 30-min sessions administered four times per day over a 4-week period. The MI group underwent an additional daily 25-min session of MIT, whereas the CON group watched neutral nature documentaries (landscapes and animals) for an equivalent duration. Functional outcomes were assessed using the Fugl-Meyer Assessment for Upper Extremity (FMA-UE) and the modified Barthel Index (MBI). Additionally, fNIRS was used to monitor changes in oxyhemoglobin (HbO₂) levels in the motor cortex before and after the intervention in the MI group. Sixty-three participants completed the study (MI group: n = 32, CON group: n = 31). Both groups showed significant improvements in FMA-UE and MBI scores after the intervention (P < 0.05). The MI group demonstrated significantly greater improvement in MBI compared with the CON group (P < 0.05), although between-group differences in FMA-UE were not significant (P > 0.05). fNIRS revealed increased cortical activation in the MI group, specifically showing enhanced activation intensity in the supplementary motor area (channel 3) and sensorimotor cortex (channels 18, 19, 21) (P < 0.05). These findings suggest that functional improvements may be mediated through neural plasticity changes. The combined application of MIT and CRT appears to enhance motor cortex activation and promote functional recovery in stroke rehabilitation.