Impact of colored light on cardiorespiratory coordination.
Background. Light exposure to the eye can influence different physiological functions, for example, the suprachiasmatic nucleus (SCN). By affecting the autonomic nervous system, the SCN may influence the heart rate variability (HRV). Standardized colored light exposure alters HRV but the results are inconsistent. In this study we investigated the effects of nonstandardized red light (approx. 640 nm) and blue (approx. 480 nm) light (approx. 50 lx) on cardiorespiratory coordination and HRV. Methods. 17 healthy subjects (7 males, age: 26.5 ± 6.2 years) were exposed to the following sequence (10 minutes each): daylight-red light-daylight-blue light-daylight. Red and blue lights were created by daylight passing through colored glass panes. Spectral measures of HRV (LF: low frequency, HF: high frequency oscillations, and sympathovagal balance LF/HF) and measures of cardiorespiratory coordination (HRR: heart respiration ratio, PCR: phase coordination ratio) were analyzed. Results. The LF component increased and the HF component decreased after red light. Consequently, LF/HF increased after red light. Furthermore, during red light HRR and PCR confined to 4 : 1, that is, 4 heartbeats during one respiratory cycle. Conclusion. Nonstandardized red and blue lights are able to alter the autonomic control reflected by HRV as well as cardiorespiratory coordination.
Integrated Curriculum for Anthroposophic Medicine, University of Witten/Herdecke, 58313 Herdecke, Germany ; Chair for Theory of Medicine, Integrative and Anthroposophic Medicine, University of Witten/Herdecke, 58313 Herdecke, Germany ; Institute for Integrative Medicine, University of Witten/Herdecke, 58313 Herdecke, Germany ; Gemeinschaftskrankenhaus Herdecke, 58313 Herdecke, Germany.
Friedrich
F
Edelhäuser
Integrated Curriculum for Anthroposophic Medicine, University of Witten/Herdecke, 58313 Herdecke, Germany.
Florian
F
Hak
Gemeinschaftskrankenhaus Herdecke, 58313 Herdecke, Germany.
Ullrich
U
Kleinrath
Gemeinschaftskrankenhaus Herdecke, 58313 Herdecke, Germany.
Birgit
B
Lühr
Institute for Integrative Medicine, University of Witten/Herdecke, 58313 Herdecke, Germany.
Peter F
PF
Matthiessen
Chair for Theory of Medicine, Integrative and Anthroposophic Medicine, University of Witten/Herdecke, 58313 Herdecke, Germany ; Institute for Integrative Medicine, University of Witten/Herdecke, 58313 Herdecke, Germany.
Johannes
J
Weinzirl
Integrated Curriculum for Anthroposophic Medicine, University of Witten/Herdecke, 58313 Herdecke, Germany ; Chair for Theory of Medicine, Integrative and Anthroposophic Medicine, University of Witten/Herdecke, 58313 Herdecke, Germany ; Institute for Integrative Medicine, University of Witten/Herdecke, 58313 Herdecke, Germany.
Dirk
D
Cysarz