There is the inferred assumption that as humans we are unencumbered by the demands levied by our biology and that we can do what we want, at whatever time & the ways we choose, even after experiencing that more than 70% of our time is spent in the indoors.
Whereas in reality every aspect of our physiology and behavior is constrained by a 24 h beat arising from deep within our evolution.
Our daily circadian rhythms and sleep/wake cycle allow us to function optimally in a dynamic world, adjusting our biology to the demands imposed by the day/night cycle.
We must not ignore the circadian and sleep systems at our peril.
The impact of chronic sleep disruption and reduced sleep on the promotion and interaction of physiological stress via the hypothalamic-pituitary-adrenal (HPA) and sympatho-adreno-medullary (SAM) axes and psychosocial stress.
Ultimately, the combined and interlocking effects of physiological, psychology and psychosocial stress lead to emotional, cognitive, and physiological pathologies
While the SCN receives inputs from the eyes via the ipRGC-mediated pathways, other neural pathways that have nothing to do with light exposure also modulate SCN function. A recent review cites a number of distinct input pathways to the SCN).
In addition, to this how can one account for supplemental exposure to blue-enriched light emanating from the cell phones, tablets, computers, and TVs in the daytime and nighttime settings. Thus the appropriate form of melatonin release and justified exposure time for the same is too very essential
These include the medial and dorsal parts of the raphe-dorsal hypothalamic pathway mediating arousal, social cues, and feeding information, and a mixed-photoreceptor responsive pathway projecting from the intergeniculate leaflet to the
CCT alone (in the absence) of the spectral power distribution of a light source –luminaire might not be helpful, since it does not provide any information as to the fractional contribution of any specific part of the spectrum (particularly blue light).
The idea that there can be an “explicit technique” for human-bio favorable lighting that can be universally applied to all persons is unrealistic, because of the tremendous variability between individuals based on their age, genetics, environmental factors, individual physiology, eating habits, wake up & sleep timings and personal behaviors. Thus, in the same manner, the response of the occupants under these installed/ specified lights with various CCT & SPD to the respective eV & frequency of light (as an energy component) is considered by many of the lighting experts & researchers.