When someone has an abnormally high sensitivity to sunlight, this is known as photosensitivity. As of 2014, no one has developed a nocturnal town for people who have photosensitivity.

In animals the main cause of photosensitivity is sunlight. In general "photosensitivity" can be defined as a reaction to any object that is receiving photons, which would include visible light and UV-light.

Something that is affected by light.

There are over three dozen diseases, two dozen drugs, a variety of herbal preparations, and several perfume and cosmetic components that can cause photosensitivity

photosensitivity