Color-selective photophobia was found to be more prevalent during the ictal vs the interictal phase in individuals with migraine, in a study published in Pain.
In a previous study, white, blue, amber, and red lights were found to worsen migraine headaches in a greater number of patients and to a greater extent compared with green light. In the current study, the investigators sought to determine whether the color preference of photophobia was phase or condition dependent.
The study included participants with migraine (n=69) and healthy control individuals (n=17). The researchers exposed participants to different colors of light at different intensities. Participants with migraine were exposed to light both during and in between migraine episodes. During the ictal phase, participants were asked to describe any change in migraine intensity. In the interictal phase for those with migraine, and in control individuals, participants were asked whether the lights triggered a headache or cranial pain.
During both the ictal and interictal phase, the proportion of participants with migraine who reported headache exacerbation in response to different colors of light increased with elevated light intensities. During the ictal phase, approximately 80% of participants with migraine reported that white, blue, amber, and red lights exacerbated their headaches, compared with 40% who said that green light did. During the interictal phase, 16% to 19% of participants with migraines reported that white, blue, amber, and red light initiated a headache compared with 3% for green light. Only 1 control participant reported a headache in response to any of the light stimuli and it was in response to the highest intensity red light.
“Given that color perception is generated in the visual cortex, the findings support the notion that the visual cortex processes colors differently in the brain of migraineurs than in the brain of subjects with no previous history of migraine,” the researchers wrote.
Nir R, Lee AJ, Huntington S, et al. Color-selective photophobia in ictal vs. interictal migraineurs and in healthy controls. [published June 12, 2018]. Pain. doi:10.1097/j.pain.0000000000001303