Color-selective photophobia in ictal vs interictal migraineurs and in healthy controls

Abstract

Aversion to light is common among migraineurs undergoing acute attacks. Using psychophysical assessments in patients with episodic migraine, we reported that white, blue, amber, and red lights exacerbate migraine headache in a significantly larger percentage of patients and to a greater extent compared with green light. This study aimed at determining whether these findings are phase-dependent-namely, manifested exclusively during migraine (ictally) but not in its absence (interictally), or condition-dependent-ie, expressed uniquely in migraineurs but not in healthy controls. To determine whether the color preference of migraine-type photophobia is phase- or condition-dependent, we compared the effects of each color of light in each intensity between migraineurs during and in-between attacks and healthy controls. During the ictal and interictal phases, the proportion of migraineurs reporting changes in headache severity when exposed to the different colors of light increased in accordance with elevated light intensities. During the ictal phase, white, blue, amber, and red lights exacerbated headaches in ∼80% of the patients; however, during the interictal phase, light initiated headache in only 16% to 19%. Notably, green light exacerbated headaches in 40% and triggered headaches in 3% of the patients studied during the ictal and interictal phases, respectively. With one exception (highest red light intensity), no control subject reported headache in response to the light stimuli. These findings suggest that color preference is unique to migraineurs-as it was not found in control subjects-and that it is independent of whether or not the patients are in their ictal or interictal phase.

The migraine eye: distinct rod-driven retinal pathways' response to dim light challenges the visual cortex hyperexcitability theory

“…This conclusion is heavily supported by the notion that color perception is generated by the visual cortex in response to signals that originate in retinal cones [11]. Along this line, we also suggested that because the generation of color perception and its processing depend on color-sensitive, cone-opponent neurons in the visual cortex [11], the most reasonable way to explain why control subjects like colored light whereas migraineurs find colored light aversive is by abnormal functioning of the visual cortex [25].…”

Update of Neuromodulation in Chronic Migraine

“…Exposure to green light may modulate nociception and anxiety. Non-green light stimuli exacerbated pain intensity during the migraine attack but not in healthy control [55]. In contrast, exposure to green light reduced pain intensity in ~ 20% of the patients (18/69 CM) [56].…”

Blue light exposure in vitro causes toxicity to trigeminal neurons and glia through increased superoxide and hydrogen peroxide generation

“…To investigate the wavelength specificity of trigeminal phototoxicity, we explored the impact of narrow 10 nm wavebands situated within the large blue-green spectrum. We chose the violet (410 nm) and the blue (440 nm) wavelengths known to be harmful for the retina [28,29], the turquoise blue (480 nm) implicated in circadian rhythms [30], the green light (510 nm) reported to be soothing for photophobic migraineurs [31,32] and also the red light (630 nm). The part of the plate was kept in the dark for the control condition; the red-illuminated part served as a second control since, to our knowledge, there are no data about any damage from red-light exposure.…”