By paranormal coincidence, I just happen to have written a book chapter on such brain-enhancement schemes. It appeared in a new book edited by Dr. Sergio Della Sala, a neurologist at the University of Aberdeen. The book is called Mind Myths: Exploring Popular Assumptions About the Mind and Brain (1999). The bottom line is, "Save your money-there's no free lunch." [Editor: the link to the book at Amazon allows you to "look inside" much of Barry Beyerstein's chapter on this subject including a section that debunks the myth that we only use 10% of our brains.]
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