Evaluation of facial temperature distribution changes during meditation using infrared thermal imaging: An experimental, cross-over study

Objective: To investigate the differences between meditation and resting states using infrared thermal imaging (IRTI) to determine facial temperature distribution features during meditation and annotate the patterns of facial temperature changes during meditation from the perspective of traditional Chinese medicine facial diagnosis.

Methods: Each participant performed 10 min meditation and 10 min resting but in different sequences. A concentration test was set as the task load, followed by a meditation/resting or resting/meditation session, during which the participants' facial temperatures were observed using IRTI. Participants were scored on the Big Five Inventory (BFI) and Mindful Attention Awareness Scale (MAAS).

Results: Forehead temperatures decreased more during meditation than during the resting state. The chin temperature increased only during meditation (P < .0001). For the subjects with meditation experience, there were significant differences in the temperatures of the left forehead (P < .01), right forehead (P < .01) and chin (P < .05) between the meditation and resting state at the 10th min. In the non-task state, the BFI-Extraversion showed a negative correlation with the temperature of the left forehead (R = −0.41, P = .03). In the post-task state, the temperature of the left forehead was negatively correlated with scores on the MAAS (R = −0.42, P = .02).

Conclusion: Using IRTI to study meditation offers a practical solution to the challenges in meditation research. The results indicate that an increase in chin temperature may be a representative feature of a meditation state, and forehead temperature is also a potential indicator.