Palinopsia
From Wikipedia, the free encyclopedia
Palinopsia (Greek: palin for "again" and opsia for "seeing") is a visual disturbance that causes images to persist even after their corresponding stimulus has left. It is similar to an afterimage seen after looking into a bright light, but in palinopsia, color inversion is rare. Also, intensity and stimulus duration have no influence on the persistence of images in palinopsia, which is in sharp contrast with afterimages.
Persistent palinopsia can be caused by vascular disease, a brain tumour, prescription medication, substance abuse (most notably LSD) or head trauma. Palinopsia can occur years after the last drug usage, either by itself or as part of a syndrome called HPPD.
Some people suffering from ocular migraine or, rarely, occipital lobe epilepsy, can also have bouts of palinopsia.
