メラノプシン細胞が不快グレアに与える影響

Abstract

Blue light often causes discomfort glare, but it is unclear which visual pigments are the main contributing factors. Thus, we conducted an experiment to clarify the effects of two visual pigments, S-cones and melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs), by applying a silent substitution method for keeping the stimulations of L and M cones intact in foveal and peripheral vision. The color temperatures of the stimuli were 2700 K and 8000 K, and the luminance value was 1000 cd/m 2 . The background luminance was set to 5.0 cd/m 2 to create photopic conditions. Participants were exposed to the discomfort glare of the two stimuli sequentially and evaluated them using pairwise comparisons. The results showed that stimulation of ipRGCs significantly increases the discomfort glare in peripheral vision whereas the stimulation of S-cones does not, indicating that ipRGCs play a crucial role in the occurrence of discomfort glare caused by blue light.

Melanopsin Stimulation Affects Discomfort Glare in Lighting Environment

“…These trends are similar to the results of previous studies on lighting environments that investigated the effect of CCTs on discomfort glare 3) . These trends differed from the results of previous study 19) that evaluated visual stimuli presented in part of the field of view. The fact that the effects of CCTs differ depending on the method of visual stimulus presentation may be related to the distribution of photoreceptors in the retina.…”

“…S-cones are located in the fovea and decrease in number as one moves from the fovea to the periphery 30) . It has been reported that melanopsin has a stronger effect on visual perception in peripheral vision than in foveal vision 19,29) , and it has long been known that S-cones contribute more to foveal vision than to peripheral vision. These findings suggest that the effect of melanopsin stimulation on discomfort glare and the degree to which S-cones suppress the effect depend on the location on the retina at which the visual stimulus is presented.…”

“…In these studies, the stimulation of S-cones, rods, and melanopsin was not directly controlled. We conducted an experiment to evaluate discomfort glare under photopic adaptation to visual stimuli in which the stimulation of S-cones and melanopsin was controlled in peripheral vision and showed that melanopsin affected the discomfort glare 19) whereas S-cones and rods did not. Because the experiment was performed on visual stimuli presented only in a part of the field of view, it is not clear whether the findings can be applied to discomfort glare caused by light in the entire field of view, that is, discomfort glare in a lighting environment.…”

Effects of a gap between the central and surrounding regions with luminance gradients on the feeling of being dazzled

“…This dissociation of the feeling of being dazzled from perceived brightness may be explained by different contributions of melanopsin containing intrinsically photosensitive retinal ganglion cells to brightness perception and to the feeling of being dazzled. The melanopsin signals affect visual discomfort (Spitschan et al, 2017) and the feeling of being dazzled (mabushisa; Higashi et al, 2022) as well as pupil responses (Gamlin et al, 2007), and photophobia and reflexive eye closure in migraine (Kaiser et al, 2021;McAdams et al, 2020). Although the melanopsin signals also affect brightness perception (Brown et al, 2012;Yamakawa et al, 2019), they seem to contribute more to visual discomfort and nonvisual responses such as eye blink and pupil responses than to bright perception.…”