Ganzfeld (“total field”) is the most popular extrasensory perception (ESP) experiment undertaken by parapsychologists. The experiment is carried out to study an individual’s ESP levels.

During the tests the subjects are deprived of their senses by lying on a couch or mattress, wearing halves of ping-pong balls over their eyes while white noise plays in earphones. During this state of deprivation, a sender attempts to psychically send a randomly select target image which is usually a video clip. Later the subject is asked to choose a clip from a selection. By chance the average subject should guess the right target 25% of the time but Edinburgh’s Koestler Parapsychological Unit often achieves 33%.

Ganzfeld could be the closest experiment to prove that ESP or PSI really exists. Because of this, Ganzfeld experiments are the most carefully conducted and scrutinized of all ESP experiments. Yet after decades of research, results have not been produced that will convince scientists that ESP does exist.