Effects After Transcranial Direct Current Stimulation of the Visual Cortex on Motor Imagery

The impact of transcranial direct current stimulation (tDCS) on motor imagery (MI) holds significant potential for neurorehabilitation. Most studies focus on tDCS of the primary motor cortex (M1), neglecting other cerebral cortex regions involved in MI. This study examines the effects of tDCS of the visual cortex using different currents (anode, cathode, sham) on MI. Eleven healthy right-handed volunteers participated in three sessions differed in the type of current used, performing the same MI tasks involving visual imagery (V1) or kinesthetic imagery (KI) of elbow joint flexion and extension. Motor-evoked potentials (MEPs) from five right arm muscles were averaged and normalized relative to the baseline before tDCS. The results showed a statistically significant effect of tDCS combined with MI on the average MEPs of conditions (Pillai trace p = 0.019), highlighting the potential for further research on visual imagination.