For those of you who are interested in Brion Gysin's Dreamachine, the following was borrowed from our friends at Wikipedia:
In its original form, a dreamachine is made from a cylinder with slits cut in the sides. The cylinder is placed on a record turntable and rotated at 78 or 45 revolutions per minute. A light bulb is suspended in the center of the cylinder and the rotation speed allows the light to come out from the holes at a constant frequency, situated between 8 and 13 pulses per second. This frequency range corresponds to alpha waves, electrical oscillations normally present in the human brain while relaxing.

A dreamachine is "viewed" with the eyes closed: the pulsating light stimulates the optical nerve and alters the brain's electrical oscillations. The "viewer" experiences increasingly bright, complex patterns of color behind their closed eyelids. The patterns become shapes and symbols, swirling around, until the "viewer" feels surrounded by colors. It is claimed that viewing a dreamachine allows one to enter a hypnagogic state. This experience may sometimes be quite intense, but to escape from it, one needs only to open one's eyes.

WARNING: A dreamachine may be dangerous for people with photosensitive epilepsy or other nervous disorders. It is thought that one out of 10,000 adults will experience a seizure while viewing the device; about twice as many children will have a similar ill effect.



An excerpt from my article, Dreamachines, Hallucinations, Charles Bonnet Syndrome&The 50 Yr Old Question Hodological Science Answered:

Almost fifty years ago, the beat poet Brion Gysin (1916 - 1986), described a visual hallucination that he experienced while riding a bus:
...Had a transcendental storm of colour visions today in the bus going to Marseille. We ran through a long avenue of trees and I closed my eyes against the setting sun. An overwhelming flood of intensely bright patterns in supernatural colours exploded behind my eyelids: a multidimensional kaleidoscope whirling out through space. I was swept out of time. I was in a world of infinite number. The vision stopped abruptly as we left the trees. Was that a vision? What happened to me? (Brion Gysin, 21 December 1958)
Gysin, a writer and performance artist, though known for his discovery of the cut-up technique, which inspired writers like William S. Burroughs, was also the co-inventor (along with scientist Ian Sommerville) of the Dreamachine, a stroboscopic flicker device designed to be viewed with the eyes closed and produces visual stimuli.

Read the full article.