by association, as a crippling fear of bright light can significantly limit the places a heliophobe can comfortably visit, as well as prevent that person from going outside during the daytime, when most other people are active.

Other medical conditions such as keratoconus (an eye disorder that results in extreme optic sensitivity to sunlight and bright lights), migraine which can be triggered by bright light, and porphyria cutanea tarda,