Background & Aims

For about two decades, many studies have shown the effectiveness of Virtual Reality (VR) as an alternative intervention for pain reduction in patients with acute and Chronic Pain(CP). One of the possible mechanisms of VR for pain alleviation is associated with the Sense of Embodiment. It is suggested that in this mechanism, akin to graded motor imagery and mirror box, VR provides a sense of embodiment in the virtual environment (often induced by using an avatar) and helps with normalizing the distorted body representation amongst CP patients. However, the impact of embodiment in VR on neural processes related to CP is yet not fully understood. In previous studies on VR embodiment, the subjective sense of embodiment has been mostly linked to lower alpha power (8-12Hz). Despite this, no previous study has investigated the influence of VR intervention on EEG signals in CP patients. This pilot study aimed to fill this gap by exploring the effects of having an avatar in VR on CP using EEG.

Methods

In an experimental pilot study, CP patients (n=14, 7/group, all female) experienced a meditative virtual environment either with or without a gender-matched, synchronized avatar. We collected their pre- and post-VR resting state EEG signals and subjective pain and sense of embodiment scores.

Results

The controlled post-Peak of Theta-Alpha Frequency (PTAF), which has been observed to be lower amongst CP patients, has been significantly (p<0.05) higher in the Avatar group. Additionally, in both conditions, we observed an increase in alpha from pre to post, with a significantly lower post-Rest frontal alpha for the Avatar group.

Conclusions

These findings suggest that having an avatar in VR may modulate neural processes related to CP, specifically in the alpha frequency bands. Further studies are needed to confirm these findings and better to understand the underlying mechanisms of VR-embodiment in CP management.

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Presenting Author

SeyedehPegah KiaeiZiabari

Poster Authors

Pegah Kiaei

Masters

Simon Fraser University

Lead Author

Zahra (Aysun) Ofoghi

PhD

The Pain Studies Lab, School of Interactive Arts and Technology, Simon Fraser University

Lead Author

Diane Gromala

PhD

The Pain Studies Lab, School of Interactive Arts and Technology, Simon Fraser University

Lead Author

Sylvain Moreno

PhD

Simon Fraser University

Lead Author

Topics

  • Pain Imaging