Comparing Motor Resonance to Virtual and Real Actions using Transcranial Magnetic Stimulation: Relevance to Virtual Clinical Consultations (Preprint)

Abstract

BACKGROUND Virtual clinical interactions have increased tremendously since the onset of the pandemic. While they certainly have their advantages, there also exist potential limitations, e.g., in establishing a therapeutic alliance, discussing complex clinical scenarios, and so on. This may be due to possible disruptions in the accurate activation of the human mirror neuron system - a posited physiological template of effective social communication. OBJECTIVE To compare motor resonance - a putative marker of mirror neuron system (MNS) activity estimated using transcranial magnetic stimulation elicited while viewing virtual (video-based) and actual or real (enacted by a person) actions in healthy individuals. We hypothesized that motor resonance will be greater during real as compared to virtual action observation. METHODS Motor resonance or motor evoked potential (MEP) facilitation during action observation relative to rest states, is an indirect measurement of MNS activity in humans. We compared MEP facilitation during the observation of virtual (presented via videos) and real (enacted in person) actions, relative to static image observation in healthy individuals (N=64) using transcranial magnetic stimulation. The MEP recordings were obtained by two single-pulse (neuronal membrane excitability-driven) TMS paradigms of different intensities and two paired-pulse (cortical GABA-interneuron driven) TMS paradigms. RESULTS On RMANOVA we observed a significant time effect for MEP facilitation from static to virtual and real observation states when recorded using three of the four TMS paradigms. Post-hoc pairwise comparisons with Benjamini–Hochberg false discovery rate correction revealed a significant MEP facilitation in both virtual and real observation states relative to static image observation; however, we also observed a significant time effect between the two observation states (real > virtual) with two TMS paradigms. CONCLUSIONS Our results indicate that social cues expressed via both virtual (video) or real (in person) modes elicit physiological responses within the putative MNS, but this effect is more pronounced for actions presented in person. This has relevance to the appropriate implementation of digital health solutions, especially those pertaining to mental health. CLINICALTRIAL -