Manipulating Light Can Induce Psychedelic Experiences – And Scientists Aren't Quite Sure Why

LONDON - Oct. 28, 2022 - PRLog -- Matthew MacKisack, University of Exeter, Reshanne Reeder, Edge Hill University

For millennia, people have used mind-altering techniques to achieve different states of consciousness, envision spiritual figures, connect with nature, or simply for the fun of it. Psychedelic substances, in particular, have a long and controversial history. But for just as long, people have been having these experiences without drugs too, using rhythmic techniques such as rocking, chanting or drumming.

Perhaps the most powerful technique of this kind is flickering light, called "ganzflicker". Ganzflicker effects can be achieved by turning a light on and off, or by alternating colours in a rapid, rhythmic pattern (like a strobe). This can create an instant psychedelic experience.

Ganzflicker elicits striking visual phenomena. People can see geometric shapes and illusory colours but sometimes also complex objects, such as animals and faces – all without any chemical stimulants. Sometimes ganzflicker can even lead to altered states of consciousness (such as losing a sense of time or space) and emotions (ranging from fear to euphoria).

Although its effects are little known today, ganzflicker has influenced and inspired many people through the ages, including the two of us. We are an art historian and brain scientist working together on an interactive showcase of ganzflicker techniques used in science and art. Our collaboration has culminated in the museum exhibition "Ganzflicker: art, science, and psychedelic experience", which is part of the 2022 Being Human festival.

Ganzflicker's effects were first documented in 1819 by the physiologist Jan E. Purkinje. Purkinje discovered that illusory patterns could appear if he faced the sun and waved his hand in front of his closed eyelids.

Near the end of the 19th century, an English toymaker and amateur scientist, Charles Benham, produced the first commercially available flicker device: a top with a monochrome pattern that, when spun, produced illusory colours that swirled around the disc.

Modified versions of Benham's "artificial spectrum top" were used in experiments well into the 20th century. William Grey Walter, a pioneering neurophysiologist and cybernetician, pushed flicker effects further by using electric strobe lights, synchronised with the brain's rhythms.

Fascinated by the mind-altering potential of Walter's machinery, the artist Brion Gysin, in collaboration with writer William S. Burroughs and mathematician Ian Sommerville, invented the Dreamachine (1962).

https://theconversation.com/manipulating-light-can-induce...

http://youtu.be/bvI1UQw35GE