Kim Peek was born in Salt Lake City, Utah with macrocephaly, damage to the cerebellum, and agenesis of the corpus callosum, a condition in which the bundle of nerves that connects the two hemispheres of the brain is missing; in Peek's case, secondary connectors such as the anterior commissure were also missing. There is speculation that his neurons made unusual connections due to the absence of a corpus callosum, which resulted in an increased memory capacity.
According to Peek's father, Fran (Francis) Peek, Kim was able to memorize things from the age of 16–20 months. He read books, memorized them, and then placed them upside down on the shelf to show that he had finished reading them, a practice he maintained all his life. He could speed through a book in about an hour and remember almost everything he had read, memorizing vast amounts of information in subjects ranging from history and literature, geography and numbers to sports, music and dates.
Peek read by scanning the left page with his left eye, then the right page with his right eye; his lack of a corpus callosum allowed the eyes to function independently. According to an article in The Times newspaper, he could accurately recall the contents of at least 12,000 books. Peek lived in Murray, Utah and spent a considerable amount of his time reading at the Salt Lake City Library and demonstrating his capabilities at schools, with great help from his father.
Kim Peek passed away in 2009.
It is claimed Peek had an eidetic memory, or photographic memory, something that people aren't even sure actually exists. However, if it does exist, Peek is probably the best case for it, reportedly being able to recall 98 percent of everything he ever experienced in perfect detail.
Peek's story was also the inspiration for the film Rain Man. However, when someone asked Peek to read a book on gambling (which would have taken him about 30 minutes), he told them that using his powers for gambling would be "unethical."
Many assumed Peek was an autistic savant. This wasn't the case; Peek's incredible ability was from his congenital birth defect, which resulted in increased memory capacity. He memorized everything, including the 12,000 books we mentioned earlier and sports statistics spanning decades. For a given person's hometown, he could tell you all highways leading to it, the county, area code and ZIP code, television stations available in the town, the name of the local telephone provider and any notable local history.
When Dustin Hoffman met him to research his role for Rain Man, he was quoted as saying, "I may be the star, but you are the heavens".