[Photosensitivity and colour filters (a systematic study on 1500 subjects) (author's transl)].

The reinforcing, activating, inhibiting or negative action of yellow, orange, red, green, and blue filters was studied in 1500 patients. A reinforcing action is seen much more frequently in subjects photosensitive to white light who are under twenty years old, while an inhibiting or negative action is more frequent in those over twenty. Two other factors seem to play a role in the reinforcing action of orange and red filters in subjects under twenty years old: epilepsy and cerebral immaturity. None of the non-epileptic subjects who developed a photo-convulsive response to yellow, orange, or red filters only, became epileptic during the two-year follow-up period.