The physicist Kristian Birkeland exposed the fraud of the direct voice medium Etta Wriedt. Birkeland turned on the lights during a séance, snatched her trumpets and discovered that the "spirit" noises were caused by chemical explosions induced by potassium and water and in other cases by lycopodium powder. The British medium Isa Northage claimed to materialize the spirit of a surgeon known as Dr. Reynolds. When photographs taken of Reynolds were analyzed by researchers they discovered that Northage looked like Reynolds with a glued stage beard.
^ Paul Kurtz. (1985). A Skeptic's Handbook of Parapsychology. Prometheus Books. p. 29. ISBN 978-0-87975-300-9 "Florence Cook was caught cheating not only before her séances with Crookes but also afterward. Furthermore, she learned her trade from the mediums Frank Herne and Charles Williams, who were notorious for their cheating." Also see M. Lamar Keene. (1997). The Psychic Mafia. Prometheus Books. p. 64. ISBN 978-1-57392-161-9 "The most famous of materialization mediums, Florence Cook – though she managed to convince a scientist, Sir William Crookes, that she was genuine – was repeatedly exposed in fraud. Florence had been trained in the arts of the séance by Frank Herne, a well-known physical medium whose materializations were grabbed on more than one occasion and found to be the medium himself."
Assuming female personas for religious ceremonies is a longstanding tradition in the region, though it has become increasingly common in recent years. One reason may be linked to a belief that females are easier to possess, said Coleman. Wearing clothes traditionally associated with women can help mediums communicate with the spirit world, according to Anukul Siripan, a 45-year-old transgender psychic from the Thai province of Lampang.
In 1917, Edward Clodd analyzed the mediumship of the trance medium Gladys Osborne Leonard and came to the conclusion that Leonard had known her séance sitters before she had held the séances, and could have easily obtained such information by natural means. The British psychiatrist Charles Arthur Mercier wrote in his book Spiritualism and Sir Oliver Lodge (1917) that Oliver Lodge had been duped into believing mediumship by trickery and his spiritualist views were based on assumptions and not scientific evidence.
Here's what happened: The experienced psychographers showed lower levels of activity in the left hippocampus (limbic system), right superior temporal gyrus, and the frontal lobe regions of the brain during psychography compared to their normal (non-trance) writing. The frontal lobe areas are associated with reasoning, planning, generating language, movement, and problem solving, which means that the mediums were experiencing reduced focus, lessened self-awareness and fuzzy consciousness during psychography.
There are many stories of religious officials who benefited from spiritual medium gifts — Baptist preachers who would hear from their deceased relatives or other spirit guides, and many other religious figures whose belief in some form of communication with spirits is verifiable. This means that not all spiritual mediums are of the Voodoo or Caribo-African religious variety.