The trance medium Leonora Piper was investigated by psychical researchers and psychologists in the late 19th and early 20th century. In an experiment to test if Piper's "spirit" controls were purely fictitious the psychologist G. Stanley Hall invented a niece called Bessie Beals and asked Piper's 'control' to get in touch with it. Bessie appeared, answered questions and accepted Hall as her uncle. The psychologist Joseph Jastrow wrote that Piper pretended to be controlled by spirits and fell into simple and logical traps from her comments. Science writer Martin Gardner concluded Piper was a cold reader that would "fish" for information from her séance sitters. The physiologist Ivor Lloyd Tuckett who examined Piper's mediumship in detail wrote it could be explained by "muscle-reading, fishing, guessing, hints obtained in the sitting, knowledge surreptitiously obtained, knowledge acquired in the interval between sittings and lastly, facts already within Mrs. Piper's knowledge." https://drive.google.com/file/d/1v-yKnSyHSOKG16JAd6WMkAyRH9zcHZJe/view?usp=sharing
In the late 1920s and early 1930s there were around one quarter of a million practising Spiritualists and some two thousand Spiritualist societies in the UK in addition to flourishing microcultures of platform mediumship and 'home circles'. Spiritualism continues to be practised, primarily through various denominational Spiritualist churches in the United States, Canada, Australia and the United Kingdom. In the United Kingdom, over 340 Spiritualist churches and centres open their doors to the public and free demonstrations of mediumship are regularly performed.
In 1891 at a public séance with twenty sitters the medium Cecil Husk was caught leaning over a table pretending to be a spirit by covering his face with phosphor material. The magician Will Goldston also exposed the fraud mediumship of Husk. In a séance Goldston attended a pale face materialization appeared in the room. Goldston wrote "I saw at once that it was a gauze mask, and that the moustache attached to it was loose at one side through lack of gum. I pulled at the mask. It came away, revealing the face of Husk." The British materialization medium Annie Fairlamb Mellon was exposed as a fraud on October 12, 1894. During the séance a sitter seized the materialized spirit, and found it to be the Mellon on her knees with white muslin on her head and shoulders.
In a 2019 television segment on Last Week Tonight featuring prominent purported mediums including Theresa Caputo, John Edward, Tyler Henry, and Sylvia Browne, John Oliver criticized the media for promoting mediums because this exposure convinces viewers that such powers are real, and so enable neighborhood mediums to prey on grieving families. Oliver said "...when psychic abilities are presented as authentic, it emboldens a vast underworld of unscrupulous vultures, more than happy to make money by offering an open line to the afterlife, as well as many other bullshit services."
On Fox News on the Geraldo at Large show, October 6, 2007, Geraldo Rivera and other investigators accused Schwartz as a fraud as he had overstepped his position as a university researcher by requesting over three million dollars from a bereaved father who had lost his son. Schwartz claimed to have contacted the spirit of a 25-year-old man in the bathroom of his parents house and it is alleged he attempted to charge the family 3.5 million dollars for his mediumship services. Schwartz responded saying that the allegations were set up to destroy his science credibility.
A widely known channeler of this variety is J. Z. Knight, who claims to channel the spirit of Ramtha, a 30 thousand-year-old man. Others purport to channel spirits from "future dimensions", ascended masters, or, in the case of the trance mediums of the Brahma Kumaris, God. Other notable channels are Jane Roberts for Seth, Esther Hicks for Abraham, and Carla L. Rueckert for Ra.
I got a psychic slap the morning of/before the Dallas police shooting. “El Centro” , the words, came into my head. No sound, no vision, etc. I knew of the school 30+ years ago when my boyfriend, who passed, attended a few seminars. I ran through my head a series questions but nothing made sense. Later that night on tv i heard the gunman was holed up there. I couldn’t breathe. This was my wake up.
Senses used by mental mediums are sometimes defined differently from in other paranormal fields. A medium is said to have psychic abilities but not all psychics function as mediums. The term clairvoyance, for instance, may include seeing spirit and visions instilled by the spirit world. The Parapsychological Association defines "clairvoyance" as information derived directly from an external physical source.