Abstract:

Since the discovery of the intrinsically photosensitive retinal ganglion cells (ipRGCs), an increasing number of studies on Non-image forming effects (NIF) of light revealed evidence for acute changes in the level of alertness, mood and cognitive performance during the biological night and day. Regarding the influence of ambient light on cognitive performance in healthy day-active people, however, studies have revealed even more equivocal findings. Light’s effect on cognition is moderated by many factors, chief among them are the parameters of light (intensity and spectrum), lighting pattern, timing (time of day and year), personality characteristics and the nature of the task. For future research should pay more attention to investigating the relationship between light level and performance with multiple manipulations of light, exploring dynamic lighting system, developing customized personalized luminaire and testing molecular biological mechanism of NIF effect of light.

Key words: ambient light, non-image forming effect, cognitive function, circadian rhythm