Abstract
Purpose :
Violet light (VL) is a part of natural sunlight with shorter wavelength than blue light and recently found to be beneficial for various parts of human health. However, the connection between VL and sleep is yet to be explored. This pilot study aims to elucidate the connection between VL and sleep quality with the hope to verify the potential effectiveness of VL therapy on sleep disorders.
Methods :
Two experiments with similar protocol were conducted. The participant was instructed to arrive before 9AM with minimal exposure to sunlight. Then, they were instructed to perform a regular deskwork for three hours, from 09:10 until 12:10. During the night, their sleep was measured using apple watch. For the first experiment, the participants were 6 university students (M/F ratio 1:1) with experiment duration of 5 days (3 Intervention, 2 Control). For the second experiment, a university student (female) performed the experiment for 2x28 days, one as control period and the other 28 days as intervention period. The main measures of this study are body temperature (only for experiment 1) and sleep stages.
Results :
For experiment 1, the body temperature differences show that the body temperature is higher before sleep compared to the sleep during the intervention periods as opposed to increasing temperature during control period. REM/NREM stages are also closer to ideal during the intervention periods, although there was no statistical significance. Statistical significance between sleep stages was found in the experiment 2, with higher N1, N3 and lower WK, REM ratio during intervention periods.
Conclusions :
In this study, the relation between VL therapy and sleep quality was analyzed. Although potential improvement to sleep quality can be seen from both short-term and long-term experiment, there is also a concern of significantly lower REM percentage during long-term experiment.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.