Application of Motor Imagery in Stroke Rehabilitation

Motor imagery （MI） refers to the conscious mental rehearsal of the actual movement process of a specific action in the brain without generating any physical movement. It is a form of active central intervention that activates neural networks similar to those involved in the execution of actual movements，thereby facilitating brain functional reorganization. MI has several advantages，including high application safety，simplicity in implementation，and low therapeutic cost，making it a valuable auxiliary tool for the rehabilitation training of stroke patients. This study reviews the concept and development of MI，the technology of motor imagery brain-computer interfaces （MI-BCI），methods for assessing MI ability，applications of MI in stroke rehabilitation，and the mechanisms of MI action. The aim is to provide a reference for the standardized application of MI in stroke rehabilitation. The methods for assessing MI ability include questionnaires （Motor Imagery Questionnaire ［MIQ］，Vividness of Movement Imagery Questionnaire ［VMIQ］，and Kinesthetic-Visual Imagery Questionnaire ［KVIQ］），psychometric approaches （psychological timing and mental rotation experiments），and other methods （temporal consistency assessment and autonomic nervous function indicators）. The applications of MI in stroke rehabilitation mainly cover upper limb motor dysfunction，lower limb motor dysfunction，swallowing and speech dysfunction，and depression following stroke. The mechanisms of MI action primarily involve exploring brain region activation during MI training using functional near-infrared spectroscopy （fNIRS），investigating cortical activity during MI training using functional magnetic resonance imaging （fMRI），examining the excitability of local cortical neurons during MI training using neuroelectrophysiological methods，and exploring the baseline characteristics of brain connectivity during MI training using resting-state functional connectivity （rs-FC）. However，there are still some limitations in the application of MI in stroke rehabilitation. For example，the mechanisms of MI action are not yet fully understood. Before initiating MI rehabilitation training，it is necessary to assess the patient's MI ability. Moreover，there is currently no unified standard for MI-assisted rehabilitation therapy in clinical practice，with many differences existing in aspects such as treatment duration，operational instructions，and specific procedures.