Effects of singing bowl exposure on Karolinska sleepiness scale and pupillographic sleepiness test: A randomised crossover study.

BACKGROUND

The aim of this study was to investigate the effects on subjective and objective sleepiness of a stay above a large struck singing bowl compared to a relaxation period in a silent singing bowl.

METHODS

Fifty-eight healthy subjects were recruited for the study, 48 participated on two days, one week apart, during the same timeslot. The Karolinska sleepiness scale was used to evaluate current subjective sleepiness, and the relative pupillary unrest index to assess objective sleepiness. In this randomized cross-over study, the intervention consisted of a 20-minute stay in a hammock while the singing bowl, positioned beneath, was struck seven times. The controlled comparator was a 20-minute stay in the same hammock above the singing bowl, but without being struck. After these two interventions subjective and objective sleepiness were re-evaluated.

RESULTS

The mean relative pupillary unrest index values after relaxation in the struck and silent singing bowl groups were 0.74 and respectively 0.71 (p = 0.460). The median Karolinska sleepiness scale value after relaxation with the struck singing bowl was 3 compared with 4 (p = 0.041) for the silent singing bowl.

DISCUSSION

This study evaluated the influence of a struck singing bowl on sleepiness during daytime. Subjective sleepiness was significantly lower after relaxation above a struck singing bowl. After gender stratification, the difference was still significant in women. Objective sleepiness was not different in both groups. Finally, we can only speculate if women may be more susceptible to subjective improvements in case of sleepiness and show another perception of relaxation in a struck singing bowl compared to men.

Déclaration de conflit d'intérêts

BH reports speaker honoraria from Otsuka, UCB, Eli Lilly, Janssen Cilag, Lundbeck Abbvie, Nutricia, Inspire; consulting/ advisory boards for Mundipharma, Benevolent Bio, Axovant, AoP Orphan, Roche; travel support from Habel Medizintechnik, Vivisol Austria. AS reports travel support from Habel Medizintechnik, OSG, UCB; support for research and consulting from Axovant. TM reports personal fees from UCB and AoP Orphan, outside the submitted work. PG is the owner of the Bell Foundry Grassmayr. There are no patents, products in development or marketed products to declare. This does not alter our adherence to PLOS ONE policies on sharing data and materials. The remaining authors declare no other competing interests.