Feasibility and compatibility of combining virtual reality and transcranial magnetic stimulation

Both virtual reality (VR) goggles and transcranial magnetic stimulation (TMS), as stand-alone tools, have proven to be valuable in neuroscience, medicine, and psychology. However, their combined use is rare due to limited data on technical compatibility and safety considerations. It is unclear whether all brain regions can be equally stimulated while in VR.To investigate the constraints of integrating VR goggles and TMS and to assess brain region accessibility, we explored 28 TMS coil positions over five 3D-printed heads outfitted with MetaQuest2 VR goggles and a TMS coil, using both MNI coordinates and 10-10 EEG system for reference. The manually accessed positions were recorded with the Localite Neuronavigation system. We subsequently investigated the discrepancies in both distance and position relative to the intended coordinates through computational analysis.The positions were classified based on the magnitude of deviation observed. Significantly, regions associated with the prefrontal cortex were largely inaccessible, making it impractical to induce the desired electric field (E-field) in the target area with VR goggles in place. Nonetheless, adjusting the stimulation parameters to increase intensity in simulation enabled the attainment of 30%, 50%, and 70% of the target E-field strength in various prefrontal cortex regions. These findings highlight the importance of computational methods for standardizing E-fields and pave the way for further research into E-fields and plasticity induced by combining TMS and VR.