Savant syndrome

Savant syndrome is not a recognized medical diagnosis, but researcher Darold Treffert defines it as a rare condition in which persons with developmental disorders (including autism spectrum disorders) have one or more areas of expertise, ability or brilliance that are in contrast with the individual's overall limitations. Treffert says the condition can be genetic, but can also be acquired, and coexists with other developmental disabilities "such as mental retardation or brain injury or disease that occurs before (pre-natal) during (peri-natal) or after birth (post-natal), or even later in childhood or adult life."

The terms idiot savant or autistic savant are also used. "Idiot" was used by the medical profession in the late 19th and early 20th century to refer to a person whose IQ was less than 20, although that usage has now given way to "profound mental retardation"; the term idiot savant is no longer regarded as a valid medical term.

According to Treffert, about half of persons with savant syndrome have autistic disorder, while the other half have another developmental disability, mental retardation, brain injury or disease. He says, "...  not all savants are autistic, and not all autistic persons are savants." Other researchers state that autistic traits and savant skills may be linked.

Characteristics

According to Treffert, something that almost all savants have in common is a remarkable memory: a memory that he describes as "exceedingly deep but very, very narrow".

Savant-like skills may be latent in everyone. Allan Snyder attempted to simulate savant impairment in normal controls by "directing low-frequency magnetic pulses into the left fronto-temporal lobe" of the brain. Differences were observed in four of 11 subjects.

Causes and pathophysiology

Savant abilities typically dwell in the right hemisphere of the brain. The vast majority of "normal" people are left brain thinkers so the question arises on how one attains right brain dominance. For savant specialist Dr. Treffert the creation of the savant begins as an unborn child in the womb. In the womb the child's two brain hemispheres are battling for dominance. This is where the male hormone testosterone comes into the equation, and also explains why the majority of savants are male. As the two hemispheres are battling for dominance the testosterone level in the male fetus reaches the level it does in an adult, and somehow shifts the normal left brain dominance to the right.

Although the vast majority of savants are born savants, there are also cases in which an individual gains savant status in later life due to a brain injury. This brain injury, which usually damages the left brain in some way, unlocks savant abilities in people who did not have them before. Examples of these rare occurrences are; Orlando Serrell who was hit by a baseball on the left side of the head at age 10 in 1979. After the accident he discovered some unusual new abilities in himself which were calendar calculating and a superior autobiographical memory.

Epidemiology

According to Treffert:

• 10% of people on the autistic spectrum have savant skills
• Less than 1% of persons with other developmental disabilities have savant skills
• 50% of savants are autistic; the other 50% have different disabilites, mental retardation, brain injury or a brain disease
• Male savants outnumber female savants by four to six times.

History

The term idiot savant was first used to describe the condition in 1887 by Dr. John Langdon Down, who is known for his description of what is known today as Down Syndrome. Working in an institution for people with mental illness, he was stunned by the occasional "idiot savant" he would come across. There are accounts of him meeting a boy who after reading a book once could recite it back perfectly, another who could do considerably large mental calculations faster than someone could write them down on paper, and a savant who could calculate time with near perfect accuracy without looking at a clock. In that time period it was a complete mystery to scientists and psychologists alike how genius can be mixed with disability. Today much more is known about savants, but it has been only within the past 20 years that the mystery of savants has begun to unravel. With the technology available now, scientists are able to look at savants brains while they think and compare and contrast those results with the brain scans of "normal" people

Society and culture

See also: Autistic savant and People speculated to have been autistic

There are some myths about savants.

• Savants can't be creative: Savants can be very creative. There are some savants who are great musicians, composers and respected artists. Some examples of very creative savants are; Matt Savage, Blind Tom Wiggins, George Widener,and James Henry Pullen.
• All savants have low IQ's: While savants IQ scores usually range around 50–100, there are some who score above 100 and in some cases at a genius level such as Temple Grandin.

Since the movie Rain Man hit the big screen in 1988, there has been increasing inquiries about savant syndrome. The original inspiration for the film was Kim Peek who met writer Barry Morrow at a ARC meeting in Texas. But as the character of Raymond developed, several other savants were included into his character as well. Dustin Hoffman met with several savants and spent time observing them before attempting to portray the condition himself.

Further reading

• Treffert DA (2000). Extraordinary People, Bantom Press, London. ISBN 0593016734
• Treffert DA (1988). "The idiot savant: a review of the syndrome". The American journal of psychiatry. 145 (5): 563–72. PMID 3282450.
• Treffert DA. "Savant Syndrome: Recent Research, Results and Resources (1999)". Wisconsin Medical Society. Retrieved 2008-03-27.