Background and Objectives: In recent years, singing bowl sound interventions have been progressively implemented in the fields of well-being, therapy and education; however, the effectiveness has only scarcely been investigated. Therefore, this study was aimed at determining neurophysiological effects of a singing bowl massage. Materials and Methods: In this prospective cohort study 64-channel EEG, ECG and respiration was recorded from 34 participants (mean age 36.03 ± 13.43 years, 24 females/10 males) before, during and after a professional singing bowl massage. Further, subjective changes in well-being were assessed. EEG data were analyzed by determining the effect sizes of distinct frequency bands. Significant differences were calculated by a two-tailed t-test corrected for multiple comparisons. Heart rate variability metrics, heart rate and respiration rate were estimated and compared. Results: Overall EEG power decreased during the sound condition compared to a task-free resting state (d = −0.30, p = 0.002). After the intervention, global EEG power was further reduced (d = −0.46, p < 0.001), revealing a decrease in the beta 2 (d = −0.15, p = 0.002) and the gamma frequency band (d = −0.21, p = 0.004). The mean heart rate was significantly lower after the intervention (75.5 ± 19.8 vs. 71.5 ± 17.9, p < 0.001) and the respiration rate higher (13.5 ± 5.3 vs. 15.2 ± 6.3, p = 0.018). 91.2% of the participants felt more integrated, 97.1% more balanced and 76.5% more vitalized. Conclusions: The neurophysiological effects of a singing bowl sound massage may be interpreted as a shift towards a more mindful, meditative state of consciousness. The intervention was perceived as beneficial for the wellbeing.
Keywords: EEG; HRV; complementary therapy; mind–body intervention; singing bowl.