Here's some interesting info on false memories and past regression therapy..
" Jean Piaget, the great child psychologist, claimed that his earliest memory was of nearly being kidnapped at the age of 2. He remembered details such as sitting in his baby carriage, watching the nurse defend herself against the kidnapper, scratches on the nurse's face, and a police officer with a short cloak and a white baton chasing the kidnapper away. The story was reinforced by the nurse and the family and others who had heard the story. Piaget was convinced that he remembered the event.
However, it never happened. Thirteen years after the alleged kidnapping attempt, Piaget's former nurse wrote to his parents to confess that she had made up the entire story. Piaget later wrote: "I therefore must have heard, as a child, the account of this story...and projected it into the past in the form of a visual memory, which was a memory of a memory, but false" (Tavris).
Remembering being kidnapped when you were an infant (under the age of three) is a false memory, almost by definition. The left inferior prefrontal lobe is undeveloped in infants, but is required for long-term memory. The elaborate encoding required for classifying and remembering such an event cannot occur in the infant's brain. "
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" Furthermore, the data of dreams is generally ambiguous. Hypnosis and other techniques that ply upon a person’s suggestibility must be used with great caution lest one create memories by suggestion rather than pry them loose by careful questioning.
Furthermore, memories are often mixed; some parts are accurate and some are not. "
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" A woman might have consciously repressed childhood sexual abuse by a neighbor or relative. Some experience in adulthood may serve as a retrieval cue and she remembers the abuse. This disturbs her and disturbs her dreams. She has nightmares, but now it is her father or grandfather or priest who is abusing her. She enters RMT and within a few months she recalls vividly how her father, mother, grandfather, grandmother, priest, etc., not only sexually abused her but engaged in horrific satanic rituals involving human sacrifices and cannibalism...The patient's memories are real and horrible, even if false. "
http://skepdic.com/falsememory.html
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" Past life regression (PLR) is the alleged journeying into one's past lives while hypnotized. While it is true that many patients recall past lives, it is highly probable that their memories are false memories. The memories are from experiences in this life, pure products of the imagination, intentional or unintentional suggestions from the hypnotist, or confabulations. "
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" The practice is given undeserved credibility because of the credentials of some of its leading advocates, e.g., Brian L. Weiss, M.D., who is a graduate of Columbia University and Yale Medical School and Chairman Emeritus of Psychiatry at the Mount Sinai Medical Center in Miami. There are no medical internships in PLR therapy, nor does being a medical doctor grant one special authority in metaphysics, the occult or the supernatural. "
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" Psychologist Robert Baker demonstrated that belief in reincarnation is the greatest predictor of whether a subject would have a past-life memory while under past life regression hypnotherapy. Furthermore, Baker demonstrated that the subject's expectations significantly affect the past-life regressive session.
He divided a group of 60 students into three groups.
He told the first group that they were about to experience an exciting new therapy that could help them uncover their past lives. Eighty-five per cent in this group were successful in "remembering" a past life.
He told the second group that they were to learn about a therapy which may or may not work to engender past-life memories. In this group, the success rate was 60%.
He told the third group that the therapy was crazy and that normal people generally do not experience a past life. Only 10% of this group had a past-life "memory." "
http://skepdic.com/pastlife.html
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If you still have doubts about how someone's mind could create a whole other life, please be sure to read this:
http://www.skepdic.com/bridey.html