He memorized every word of every book he had ever read, estimated at around 9000 plus. Each eye could read a page independently.
The main cause of his remarkable abilities is the lack of connections between his brain’s two hemispheres. An MRI scan revealed an absence of the corpus callosum, the anterior commissure and the hippocampal commissure, the parts of the neurological system that transfer information between hemispheres. Peek’s ability to retain large amounts of information may have also had something to do with his excessively large head and a correspondingly huge brain. Kim’s head was so heavy that it took several years before he could hold it up on his own.
Kim Peek was unable to “reason his way through” mathematical problems. Despite his brilliant mind, his IQ was 87, significantly below normal.
As a baby, he was diagnosed with mental retardation, and his physicians told his parents that he never would be able to read or talk. They recommended sending him to a mental institution.