BACKGROUND
Mindfulness-based stress reduction (MBSR) has shown some evidence of efficacy in the management of chronic pain. More recently virtual reality (VR) guided meditation has been used as a technique to assist MBSR. A number of studies have also explored changes in the brain during mindfulness meditation practices, but not with use of electroencephalograph (EEG) during VR guided meditation.
OBJECTIVE
This pilot study explored the potential for recording and analyzing EEG during VR-experiences, and how the power of EEG wave forms, topographic mapping and coherence measures altered during a VR-guided meditation experience in participants with chronic pain associated with a cancer diagnosis
METHODS
Ten adult cancer chronic pain patients underwent an experimental VR-guided meditation experience whilst EEG signals were recorded during the session using a BioSemi ActiveTwo system with 64 channels in a standard 10-20 configuration. The experimental EEG recording session consisted of a resting condition (pre), three VR-guided meditation conditions (med), and a final rest condition (post) and lasted for approximately one hour in total for each participant. The EEG data collected was preprocessed to remove noise and artifacts. Power spectral density (PSD) was computed over the 50 conditions utilizing the Fast Fourier Transform method, and a topographic analysis, including coherence exploration, was undertaken. Additionally, exploratory statistical analysis for possible correlations between pain scores and EEG signal power were undertaken.
RESULTS
The greatest power variations between the resting and meditation conditions straddled the conventional frequency bands and had distinct onset and offset boundaries. Power in the 6-11 Hz range exhibited a difference between the Pre and Med conditions and the Post condition. In the 11-21 Hz range, power in the Pre condition was lower than Med and Post. In the 21-55 Hz range, the Med condition had the highest power level, while the Post condition had the lowest.
Topographically, several peak channels emerged in the data (FCz, Oz, POz, CP5 and CP6. Coherence variations arose between the three peak channel pairs of interest (FCz and POz, FCz and Oz, CP5 and CP6). A repeated measures correlation analysis, for pain and EEG power for FCz, CP5 and CP6 showed a P-value close to 0.05 all in the 11-21 Hz frequency ranges.
CONCLUSIONS
This pilot study on the effect of VR-guided meditation, demonstrates the feasibility of EEG recording and subsequent data processing/analysis during VR meditative experiences. Alterations in power and coherence, mainly in 6-11 Hz and 11-21 Hz alpha-theta bandwidths were identified. Topographically, a relative decrease in the 21-55 Hz (gamma bandwidth) in the Post condition compared to the Pre condition occurred in the central-parietal regions accompanied by a change in coherence. These findings suggest that distinct altered neurophysiological brain’s signals during VR-guided meditation are detectable.
CLINICALTRIAL
clinicaltrials.gov: NCT 02995434
Virtual Reality Technologies and Chronic Pain
