Cryptomnesia

The term "cryptomnesia" literally means hidden or forgotten memory, but a more scholarly definition would be:  "the retention of unconscious memory of information learned through normal channels."  The term was first coined by a psychology professor by the name of Theodore Flournoy, and studied at length by psychologist Carl Jung.  Jung believed that cryptomnesia was a necessary function of the human mind in which information learned is subsequently forgotten in order to prevent an information overload in the brain.  When subjected to certain triggers, or accessed through hypnosis, this information can be recovered.

Cryptomnesia is often a skeptical explanation given to cases of suspected reincarnation, but it plays several roles in the paranormal field, including alleged cases of psychic mediums.  In fact, the first recorderd case of cryptomnesia occurred in 1874 when an English medium by the name of William Stanton Moses seemingly channeled the spirits of two Indian brothers who had recently passed away.  When investigators researched the case, it was discovered that an obituary recently ran for the two brothers.  Everything that was said in the seance was in the obituary, with no additional information.

Another case where cryptomnesia turned out to be a likely cause for suspected paranormal phenomena was in 1977, when a woman named Jan underwent a past life regression hypnosis session.  While discussing details of her past life, Jan discussed an accused witch by the name of Joan Waterhouse.  The witch was tried and set free in the year 1566.  However, Jan gave the erroneous date of this event as 1556.  As it turns out, 1556 was a misprint found in a Victorian reprint of the event, and a copy of such is on display at the British museum.

Cryptomnesia doesn't necessarily have to manifest as a false paranormal phenomenon, however.  Many cases of plagiarism have also been attributed to cryptomnesia.  Helen Keller's The Frost King is believed to be the product of cryptomnesia stemming from Margaret Canby's The Frost Fairies.

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