An art installation known as "Zee," on display at 943 Liberty Avenue in Pittsburgh, has been shut down after inducing a third seizure in three days. Zee is part of the Pittsburgh Festival of Firsts, although it is not the first time this installation has been in Pittsburgh. Zee was available for artgoers to experience on Wood Street in 2008 and on Liberty Avenue in 2009, and caused seizures in some viewers on those occasions as well.
The Pittsburgh Tribune was unable to obtain a comment from artist Kurt Hentschlager, but noted that the exhibit may reopen in an altered state to finish its run, scheduled to end October 27th. The Pittsburgh Cultural Trust website notes that the exhibit is restricted to people 18 and older, and the Tribune notes that artgoers must sign a waiver acknowledging the risks of "intense stroboscopic light in combination with thick artificial fog."
Photosensitive epilepsy is a known medical condition in which an individual enters a state of seizure activity due to one or more visual stimuli. One particularly well publicized event was the hospitalization of roughly 700 individuals in Japan for seizures induced by red flickering light on a television broadcast of Pocket Monsters (Pokémon). In addition to the hospitalized people (mostly children), between 5% and 10% of Pokémon viewers experienced seizure activity insufficient to warrant hospitalization. A team of Japanese researchers studied the visual material and its effects and determined that risk factors for visually induced seizures include red flicker and flickering geometric patterns.
British researchers pursuing a separate investigation (not of Pokémon) note that stimuli such as stroboscopic lights and other types of repetitive sensory input can have different effects on sensitive individuals, and that it is important to determine which stimuli produce which responses. Indeed, even properly functioning televisions pre-dating the digital era were known to cause seizures in sensitive individuals due to low-level flickering. Researchers in the Netherlands believe that prescription glasses with tinted lenses may help some individuals to avoid photo-induced seizures. It seems wise for individuals to take art exhibit warnings seriously and not assume that installations open to the public are safe for everyone.