Dark side of night lighting: effects of light spectra on neurosensory function
The nighttime environment has changed dramatically since the invention of electric lighting, in which as much as two-thirds of the world's populated areas are currently above the threshold set for light pollution. However, research on the effects of light pollution has been marked by a lack of connection between biomedical studies in the laboratory and fitness consequences. Moreover, governments and agencies are now replacing fluorescent lighting with LEDs for economic reasons. Full spectra LEDs emit short wavelengths that are known to be disruptive to sleep, health, and hormone balance. The disruptive effects of light pollution may be mitigated by leaving out certain wavelengths, but the impacts of these spectra on physiology and health, especially in relation to sensory neurobiology and stress physiology, are largely unknown. Merging neurobiology, mechanistic and behavioral approaches is a way forward to uncover the proximate as well as ultimate consequences of artificial light at night. We will use zebra finches, Taeniopygia guttata, which serve as ideal, diurnal model organisms to test the effects of nocturnal lighting with adapted spectra on stress physiology, circadian gene expression, and neurosensory function.