A form constant is a type of geometric pattern that a person usually sees when he is hallucinating or has entered “the altered state of consciousness.” It is often recurring. The patterns can vary widely, from spirals, squiggly lines, to tunnel-like images. Some patterns may not be as different as those geometric images one sees in a kaleidoscope. People who see a form constant may also experience it more closely, such as being pulled in towards the tunnel he is seeing.
The concept of form constant was first discovered in the 1920s by Heinrich Klüver, a German-American psychologist who was then studying the effects of chewing peyote, a cactus plant that has a significant part in rituals of Native American tribes. He began his experiments by enlisting volunteer subjects willing to ingest peyote and documented the results. Klüver observed very similar descriptions in his subjects’ testimonies of what they see when under the influence of peyote, such as moving shapes, distorted lines, and the presence of vibrant colors. He dubbed the images as “form constants.”
Based on his observation, Klüver grouped prevalent form constants in four categories: the chessboard pattern, cobwebs, tunnels, and spirals. Under the chessboard design, lines usually intersect, creating squares, triangles, and any crisscross patterns. Hexagons that form a honeycomb image are also classified under this category. Images of tunnels and spirals tend to be very similar, but the tunnels have a distinguished center, which can either contain light or just plain darkness. It is possible that a form constant does not fit into any categories, as the images can vary widely.
Many psychologists and scientists have tried to explain the phenomena of the form constant. One plausible theory is that when a person is hallucinating or is having a “high,” the visual cortex, the part of the brain that processes images, experiences some “noise” or interference, causing the images to become distorted, creating a form constant. One can use the television set as an analogy: when a thunderstorm upsets the transmission between the TV’s antenna and the network’s signal, the picture comes out hazy or distorted.
A form constant can be seen and experienced not only through stimulated hallucinations, but also through naturally occurring ones, as well as other forms of psychosis and delusions. Near-death incidents can also induce the images, as well as severe migraines. Form constants have also become an inspiration for “psychedelic art” that uses similar elements such as vibrant colors and various repetitive shapes.