Motor Imagery-based Neurofeedback Using Visual, Auditory, Vibrotactile, and Proprioceptive Senses: A Randomized Controlled Trial

Motor imagery (MI)-based neurofeedback (NFB) has recently been shown to improve MI ability using visual, auditory, vibrotactile, and proprioceptive modalities; however, no study has compared all four of these sensory modalities to each other and to a control group. This randomized controlled trial aimed to examine the effects of MI-based NFB on MI ability (the ability to improve one's motor abilities through visualizing movements) using visual, auditory, vibrotactile, and proprioceptive modalities. Fifty healthy young participants were recruited for this study and were randomly assigned to the control group or an NFB group using either visual, auditory, vibrotactile, or proprioceptive sensory feedback. All participants completed a pre-training evaluation of 20 trials without NFB. Next, 60 trials of the MI task (imagining themselves performing maximal dorsiflexion of the wrist joint) were performed during the training phase. After training, all groups were again assessed without NFB for 20 trials. For each NFB group, EEG was measured during the MI task, and event-related desynchronization (ERD) in motor-related areas was fed back to the participants in real time. The pre- and post-training results of ERD and subjective MI vividness were compared for each group; the results showed that ERD significantly increased after training in all four groups that performed NFB (p < 0.05) and that MI vividness increased significantly after training in all five groups (p < 0.05). The present study demonstrated that MI-based NFB using visual, auditory, vibrotactile, and proprioceptive modalities improved MI ability.