Barfogenic zone: In visual media, a range of about 4 to 12 frames per second—between a slow, jerky frame speed and a more realistic-seeming 30 frames per second. In that middle range, viewers may experience nausea and vomiting, also called cybersickness.
The barfogenic zone was first identified and named by Thomas P. Piantanida, principal scientist of SRI International’s Virtual Perception Program, who in the early 1990s conducted experiments with 3D goggles for video gamers. According to a 1992 cover story about virtual reality in Business Week, Piantanida discovered that in that uncomfortable middle range “the confusion between what the brain expects and what it sees can make viewers sick.”
Thanks to 3D cinema and TV, “we may now be heading back to the barfogenic zone,” writes Tom Hecht in the Dec. 25, 2010 issue of New Scientist. (“3D TV: Beware the Barfogenic Zone”; full text available to subscribers only.)
The technology behind [3D entertainment] has improved in recent years, but the basic concept has not changed. A pair of specs feeds each eye with the same image from a slightly different viewpoint, which tricks us into gauging depth …
The trouble with such trickery is that it can cause an affliction called cybersickness, says Judy Barrett of the Australian Defence Science and Technology Organisation, who wrote a report on the issue in 2004. … It starts with eye strain, disorientation and a headache, and can lead to nausea. The reason is a sensory conflict between the movement of your eyeballs and lenses. When your pupils are directed at, say, this page, the eyes turn slightly inwards as you bring the page closer to your face so that your gaze can converge on a word. Meanwhile, the lenses in your eyes change shape to focus the incoming light from the moving page surface onto the retina. Your brain is used to these two movements working in tandem.
Cybersickness tends to increase with proximity to the screen. That means 3D cinema is likely to score lower on the spew scale than 3D goggles, says Paul DiZio of Brandeis University in Waltham, Massachusetts. Television is a different matter, because viewers regularly sit closer. … People are also likely to watch 3D TV for longer periods than a single movie, which puts the visual system under more strain, and so makes a lunch reappearance more likely.
According to Hecht, sports coverage “is particularly prone to uncomfortable effects, because the action can’t be choreographed at all. In addition, spectators close to the camera may suddenly pop into a shot, appearing in the viewer's lap in a flash.”
Barfogenic was coined from barf, “to vomit,” US slang, probably onomatopoetic, in use since about the 1950s (first published citation was in Dictionary of American Slang, 1960); plus –genic, a combining form meaning “generating” or “producing”; linked by –o- in imitation of carcinogenic and other words.