By Peter Kaidheim
“First, close your eyes. Now, with your index fingers at the inner edge of your eyeballs, press in and toward the temples. Press until it’s slightly painful and keep at it for about ten seconds.”
“Like this?”
“That’s right. Now what do you see?”
“The darkness is disappearing. There’s a very bright light swelling up in the center of my eyes. It’s getting even brighter. And now there’s a kind of crisscross pattern coming up from inside the light, like a checkerboard with luminous squares.”
“Good. Release the pressure for a few seconds, but keep your eyes closed. Now, press again and tell me what you see.”
“I see wavy lines this time—lots of them. Colored lines, bright blues and greens. They’re sliding across my eyes from left to right. Reminds me of tripping on acid.
“Okay. Now take your fingers away, open your eyes and focus them quickly on the white wall over there. Can you still see any wavy lines?”
“You’re right. I can.”
What is taking place is a demonstration of phosphene hallucinosis conducted by Dr. Gerald Oster, professor of biophysics at Mount Sinai School of Medicine in New York. Essentially, phosphene vision is what the followers of Sat Guru Maharaj Ji, the erstwhile perfect Master at 13, used to call the light. When you showed up at a Maharaji ashram, the senior premies, would hold you in a no-food state of sensory deprivation for 48 hours, then press down hard on your eyelids and then you’d see the light. They claimed that only the Perfect Master’s chosen adepts could administer the light, but, as we now know, anybody with eyes to see and two fingers to jab into them, à Ia Moe Howard, can enjoy this trippy, optical delusion in the privacy of their own home at no cost whatsoever. Truly the spirits rule us. Nobody knows exactly what phosphenes are. The word comes from Greek phos (“light”) and phasno (“to show”), and means what we see when we’re “seeing stars.” What they might be are sparks of pure energy, light perceived at the moment of its conversion into nervous-system information between the cornea and the brain. Thus, phosphenes may be the behavior of atomic particles as observed by the naked eye: the interface of two worlds, the normal and the nuclear—the fourth dimension. Through phosphenes you can, like Luke Skywalker, “switch to hyperspace”—just by closing your eyes or using your head to catch a baseball.
Phosphene images are common to all people, except the congenitally blind. The sophisticated experiments currently being conducted in the laboratories of optic researchers like Dr. Oster is part of a tradition of phosphene research that stretches back at least two centuries.
When Benjamin Franklin was serving as ambassador to France during the eighteenth century, one of the parlor games then popular called for a group of guests to form a circle, clasp hands together and take hold of a static electricity generator. The result was a pleasing electrical boost. One night, Franklin noticed that if you close your eyes when the jolt hits, you see a variety of luminous shapes—flickering filigrees of light and showers of bright sparks.
Since Franklin’s discovery that phosphenes can be electrically induced, most phosphene research has employed electrical stimulation in one form or another. Alessandro Volta, father of the volt, discovered that phosphenes are produced only at the making and breaking of the electrical circuit, not during the time of current flow. Volta also found that the easiest way to induce phosphenes electrically is by placing electrodes at the temples. In one of Volta’s experiments he moistened one hand and took hold of an electrode with it. He then touched the other electrode to his forehead, producing a “light, moderately bright,… [that] appears like a luminous circle, under which figure it presents itself also in several other experiments.”
In the early part of the nineteenth century, the Bohemian physiologist Jan Purkynë found that by applying one electrode to his forehead and another to his mouth, while making and breaking the current with a string of metal beads, he could produce a fairly steady flow of phosphenes. Purkynë’s interest in phosphenes, like Dr. Oster’s, apparently had its roots in deeper questions concerning the nature of human consciousness. In an essay on the physiology of the eye, Purkynë wrote: “The eye, by its uninterrupted relation to the brain, appears to be a special organ of fantasy.”
A more recent contributor to our understanding of phosphenes was the late Max Knoll, a German scientist best known as one of the builders of the electron microscope. In his laboratory in Munich, Knoll employed modern electrical equipment (a square-wave generator) to generate a more stable kind of on-off current than Purkynë had been able to produce with his metal beads. Knoll found that by varying the frequency of the electrical pulse administered to his subjects he could change the character of the phosphenes they were seeing. According to Knoll, pulses in the range from 5 cycles per second to 40 cycles per second (the same frequency as brain waves) are the most effective for producing phosphenes. By analyzing sketches drawn by the participants in his experiments, Knoll was able to identify 15 classes of phosphene figures. He also provided evidence which showed that each class of phosphene pattern was linked to a very specific frequency range.
Investigation of the frequency-dependence of phosphenes is currently being continued by Dr. Oster, who has theorized about the causes of that dependence. In an article Updated in Scientific American several years ago, Oster wrote:
Phosphenes may be the behavior of atomic particles as observed by the naked eye: the interface of two worlds, the normal and the nuclear— the fourth dimension.
The frequency dependence of phosphenes’ form is suggestive of some kind of resonance phenomenon, with different groups of nerve cells acting together when they are driven electrically at a certain rate.
Much of the evidence gathered by Oster seems to support his resonance theory. He discovered that the flickering phosphenes produced by electrical stimulation disappear if the frequency of the electrical pulse exceeds 40 cycles per second. Oster described the eerie visual effect that takes place when the critical frequency is surpassed: “The phosphenes suddenly disappear, leaving one with a feeling of being alone in space.”
All the research into the nature and function of phosphenes so far has produced no clear and complete understanding of the hows and whys of these subjective images. But even the partial picture now available is filled with important and often fascinating details about this visual phenomenon. It is known that there are a variety of nonelectrical causes for phosphenes. You don’t necessarily have to wire your temples to a Lionel train transformer to give yourself a phosphene show.
One obvious method of seeing stars is to administer a sharp blow to the head. Vacationing in Paris several years ago, Dr. Oster discovered that a relatively safe way to bring on a phosphene show was to hit himself on the back of the head with a French bread.
Other causes of phosphenes are migraine headaches and alcohol. Alcoholics who have progressed to the stage of delirium tremens are especially susceptible, which helps to explain the tendency of delirium tremens victims to see “spiders” and other shapes where they really don’t exist. Of course, the most venerable method of inducing phosphenes is a method widely practiced before the first scientific laboratory was even imagined— stimulation with psychoactive chemicals. As Oster says, “Phosphenes appear to be a significant feature of psychedelic intoxication.” Indeed.
Although hallucinogenic drugs were not employed in scientific research on phosphenes until Max Knoll first administered LSD to some participants in his experiments, “unscientific” awareness of the relationship between psychedelics and phosphenes goes back practically to prehistory. The literature of psychedelics drugs, from the Rig-Veda to Leary, contains an abundance of similar descriptions of what can only be phosphene imagery. A typical example of such a description is the following passage from Heinrich Klüver’s classic Mescal and Mechanisms of Hallucinations. After swallowing peyote buttons for the first time, Klüver reported seeing:
…clouds from left to right through optical field. Tail of a pheasant (in center of field) turns into bright yellow star; star into sparks. Moving scintillating screw; “hundreds” of screws. A sequence of rapidly changing objects in agreeable colors. A rotating wheel in the center of a silvery ground.
Not surprisingly, subjects who received hallucinogens in Knoll’s experiments reported “visions” similar to Klüver’s, leading Knoll to conclude that small amounts of hallucinogenic drugs, such as LSD, produce phosphene images that are dramatically “more elaborate.”
Writing in Timothy Leary’s Psychedelic Review in 1966, Oster described his experiment with LSD and the insights he gained about the nature of phosphenes while under the influence of the drug. During the course of his six-hour trip, he studied a number of moiré patterns that were projected onto a white wall by means of an overhead projector. Moiré patterns are “figures produced by the overlapping of two or more families of lines; the locus of points of intersection form the moiré pattern.” Oster’s observations led him to conclude that all vision has a circular pattern superimposed on it by the curved nerve fibers surrounding the retina of the eye. Under normal conditions, we are not aware of the pattern created by these nerve fibers, but psychedelic drugs make us aware of this circular “screen” by means of the moiré effects it creates when we open our eyes and look at objects in the real world. In other words, the pattern of lines in the eye’s “screen” interacts with the lines formed by the objects we are viewing to cause the shimmering, dynamic quality.
Anyone who has visited an exhibition of op art paintings by artists such as Vasarely, Bridget Riley, Larry Poons or Gerald Oster (that’s right, he’s also a well-regarded op artist) is likely to be familiar with moiré patterns. In fact, the techniques of op art are a direct outgrowth of what optic research has taught us about the functioning of the human eye. The 1965 “Responsive Eye” exhibit at New York’s Museum of Modern Art—the first major exhibition of op art paintings—was a veritable supermarket of phosphene imagery. The artists represented in the exhibit manipulated lines and colors in their paintings so as to create works of art that are exercises in pure perception. In the words of the “Responsive Eye” catalog, “by creating special optical effects (but on a flat surface!) we remove it from the outside world and take it into that terra incognita between the cornea and the brain.”
The op art painters of the Sixties were hardly the first artists to delve into that terra incognita and return with phosphene-based images, however. Examples of phosphene shapes can be found in artwork from such divergent sources as prehistoric cave paintings in Almería, Spain, and woven tapestries from Peru’s Incan civilization. The basic 15 phosphene shapes identified in the course of Max Knoll’s research can be seen in the folk art of many different cultures, from prehistory to the present. The importance of phosphenes in the development of art is a topic that has not yet been thoroughly explored. But as Dr. Oster says, “Art historians might well consider the possible effects of phosphenes as an ‘intrinsic’ source of inspiration for men of many different societies when they are speculating on relations and cross-influences among primitive societies.”
Much remains to be explained about the mystery of phosphenes and their connection to the complex functioning of the human brain, but even the knowledge we now have of these internal light shows holds enormous implications for our understanding of awareness and perception.
In Carlos Castaneda’s Tales of Power, the sorcerer don Juan says that humans are “luminous beings” made up of “luminous fibers” but that most humans are not attuned to noticing this condition. Nonsense, most rational people would say. Yet one of the important implications of the knowledge gained from phosphene research is certainly that we are indeed capable of planes of awareness that go beyond what now passes for “normal” perception. It has often been acknowledged that our awareness of the external world is conditioned by the limits of our sense perceptions. By expanding these limits, we expand our world.
Read the full issue here.
