In 1960, psychic investigator Andrija Puharich and Tom O'Neill, publisher of the Spiritualist magazine Psychic Observer, arranged to film two seances at Camp Chesterfield, Indiana using infrared film, intending to procure scientific proof of spirit materializations. The medium was shown the camera beforehand, and was aware that she was being filmed. However, the film revealed obvious fraud on the part of the medium and her cabinet assistant. The exposé was published in the 10 July 1960 issue of the Psychic Observer.:96–97
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.