Exploring Motor Imagery as a Therapeutic Intervention for Parkinson's Disease Patients: A Scoping Review

Motor Imagery (MI) has emerged as a promising therapeutic approach in the rehabilitation of individuals with Parkinson's Disease (PD). MI entails mentally rehearsing motor actions without physically executing them. This cognitive process has garnered attention due to its potential benefits in aiding motor function recovery in PD patients. Its role in complementing traditional treatment approaches is likely to reverberate throughout clinical practice. This study strives to provide a comprehensive examination several MI protocols designed for individuals with PD. The focus was to underscore the outcomes observed across motor symptoms, balance, gait, and quality of life. Methods: A literature search was carried out in the following databases: Medline, Embase, Cochrane, and PEDro, from the first publication to February 2024. Study with at least one keyword in relation to PD and MI in the title were included. Results: Of the 262 studies 53 were included. Twelve RCTs with a mean PEDro score of 6.6/10 and 41 descriptive and non-RCT studies. Among the RCTs, there were almost exclusively MI on balance, gait, and lower limbs exercise. They found an 85.2% improvement for the experimental group on the TUG with a cognitive task (p<0.02), 5.8% on the TUG (p<0.05), a 5.1% improvement in walking speed (p<0.05), other variables did not show significant improvement. For the descriptive and non-RCTs studies, there were various tasks and outcomes for the lower and upper limbs. It was shown that there was no difference in execution time in MI between patients with PD and HS, while in ME patients with PD were slower. For the upper limb, several tasks were proposed, such as thumb opposition, joystick movements and writing tasks with variable results. RCTs were more focused on balance, lower limb and walking, there was no specific outcome for the upper limb and speech. The heterogeneity of the tasks and outcomes across all included studies is also a limitation. Conclusion: To summarize, the current research on walking disorders in PD shows promise, but further investigations are crucial, particularly with an emphasis on upper limb function and speech. A need exists for studies with larger sample sizes, utilizing precise methodologies, and specifically targeting these areas to enhance our comprehension of the potential advantages of MI in the context of comprehensive PD rehabilitation. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This work was supported by the ANER program, from Region Bourgogne Franche Comte (contract ANER PARK-IMAGE, 2021Y-08279). ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes The original contributions presented in this study are included in this article/supplementary material, further inquiries can be directed to the corresponding authors.