EEG Source Localization of μ-Rhythm Event-Related Desynchronization during Tactile Imagery

Tactile imagery remains a relatively understudied phenomenon of mental imagery research. However, this technique holds promise as an effective tool for sensorimotor rehabilitation following stroke and spinal cord injuries alongside motor imagery. In this study, conducted with 22 healthy volunteers, the authors investigated the source localization of μ-rhythm event-related desynchronization (ERD) using multichannel electroencephalogram recordings and subsequent inverse problem solution with the sLORETA. All participants exhibited ERD during tactile imagery task and under vibrotactile stimulation. It was demonstrated that μ-rhythm ERD during both vibrotactile stimulation and tactile imagery was localized in the sensorimotor areas of the contralateral hemisphere. Within the source space, ERD in the postcentral gyrus was significantly stronger compared to the precentral gyrus. These findings indicate that tactile imagery, akin to the perception of real tactile stimuli, leads to prominent activation of sensorimotor cortical areas, consistent with the general understanding of the shared neural substrate during mental imagery and perception.