Dreamachine

The Dreamachine (or Dream Machine) is a stroboscopic flicker device that produces visual stimuli. Artist Brion Gysin and William S. Burroughs's "systems adviser" Ian Sommerville created the Dreamachine after reading William Grey Walter's book, The Living Brain.

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 of between 8 and 13 pulses per second. This frequency range corresponds to alpha waves, electrical oscillations normally present in the human brain while relaxing. The Dreamachine is the subject of the National Film Board of Canada 2008 feature documentary film FLicKeR by Nik Sheehan.

A Dreamachine is "viewed" with the eyes closed: the pulsating light stimulates the optic nerve and thus alters the brain's electrical oscillations. Users experience increasingly bright, complex patterns of color behind their closed eyelids (a similar effect may be experienced as a car passenger; close your eyes as the car passes through flickering shadows cast by roadside trees). The patterns become shapes and symbols, swirling around, until the user feels surrounded by colors. It is claimed that by using a Dreamachine one may enter a hypnagogic state. This experience may sometimes be quite intense, but to escape from it, one needs only to open one's eyes. The Dreamachine may be dangerous for persons 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.

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