By Scott Barry Kaufman | February 25, 2014 | Scientific American
There’s a scene in the 1988 movie Rain Man in which Raymond Babbitt (played by Dustin Hoffman) recites a waitress’s phone number. Naturally the waitress is shocked. Instead of mental telepathy, Raymond had memorized the entire telephone book and instantly recognized the name on her nametag.
Hoffman’s character was heavily influenced by the life of Kim Peek, a real memory savant who recently passed away. Peek was born without a corpus callosum, the fibers that connect the right and left hemispheres of the brain. He was also born missing parts of the cerebellum, which is important for motor control and the learning of complex, well-rehearsed routines.
When Peek was 9 months old, a doctor recommended he be institutionalized due to his severe mental disability. By the age of 6, when Peek had already memorized the first eight volumes of the family encyclopedia, another doctor recommended a lobotomy. By 14, Peek completed a high school curriculum.
v Peek’s abnormal brain wiring certainly came at a cost. Though he was able to immediately move new information from short-term memory to long-term memory, there wasn’t much processing going on in between. His adult fluid reasoning ability and verbal comprehension skills were on par with a child of 5, and he could barely understand the meaning in proverbs or metaphors. He also suffered deficits in the area of self-care: he couldn’t dress himself or brush his teeth without assistance.
But what Peek lacked in brain connections and conceptual cognitive functioning, he more than made up for in memory. He had the extraordinary ability to memorize any text in just one sitting. With two pages in front of him, he had the uncanny ability for each eye to focus on a different page. His repertoire included the Bible, the complete works of Shakespeare, U.S. area codes and zip codes, and roughly 12,000 other books. He was known to stop performances to correct actors and musicians who had made a mistake! He could also tell you what day of the week your birthday fell on in any year.
Toward the end of Peek’s life, Peek showed a marked improvement in his engagement with people. He also began playing the piano, made puns, and even started becoming more self-aware. During one presentation at Oxford University, a woman asked him if he was happy, to which he responded: “I’m happy just to look at you.”
The trade-off between memory and meaning is common among savants. The purpose of memory is to simplify experience. We didn’t evolve memory to be precise. Instead, we extract meaning wherever we can so that we can organize the regularities of experience and prepare for similar situations in the future. But without the imposition of meaning, savants can focus on literal recall. Some savants even have hyperlexia, which is the opposite of dyslexia. They are precocious readers, but have no comprehension of what they are reading.
Descriptions of savant syndrome first appeared in the scientific literature as early as 1789. In 1887 the British doctor J. Langdon Down (who discovered Down syndrome) described 10 people with savant syndrome and coined the term “idiot savant” (which is no longer used, because of its pejorative connotation). Today, one in ten people with autism have savantism, although only half of the documented savants are autistic. The rest have some other kind of developmental disorder.
Savantism disproportionately affects males, with about five male savants for every one female, and the syndrome generally occurs in people with IQs between 40 and 70. Like others with ASD, when savants take IQ tests they tend to score higher on nonverbal problems than verbal problems. As Darold Treffert, a world-renowned expert on savant syndrome, observes, “IQ scores, in my experience with savants, fail to adequately capture and reflect the many separate elements and abilities that contribute to ‘intelligence’ overall in everyone.”
Like others on the autism spectrum, savants display a narrow repertoire of skills, which tend to be highly structured, rule-based, and nonverbal. Common savant domains include music, art, calendar calculating, lightning calculating, and mechanical/visual spatial skills. Most musical savants are blind and have perfect pitch, most artistic savants express themselves through realistic drawing and sculpture, and most rapid calculating savants have a fascination and facility with prime numbers.
Even so, savants vary markedly in their abilities. Savant skills fall along a continuum, ranging from “splinter skills” (such as memorization of license plates), to “talented” savants who have musical or artistic skills that exceed what is expected based on their handicap, to “prodigious” savants where the skill is so remarkable it would be impressive with or without the disability. To date, fewer than 100 prodigious savants have been documented. Interestingly, there is almost always no “dreaded trade-off ” between the incredible skills of savants and their development of language, social skills, and daily living functioning.
Savant syndrome can be congenital or acquired. When congenital, the skill appears early in childhood, and when acquired, abilities appear to spring forth suddenly following stroke, brain injury, or dementia. Many savants are creative, in additions to being highly skilled.
