Recent research suggests that being a savant may be linked to deficiencies in the brain's left hemisphere, Linda Marsa writes in The Atlantic.
Individuals with savant syndrome have both major cognitive difficulties, such as those associated with autism, and exceptional talents in areas like music, art, or math.
There is debate in the scientific community over how common savantism is, with studies finding that anywhere from one in 10 to one in three people with autism are savants.
Some experts contend that what appears to be savantism may actually just be a symptom of autism.
"People with autism are natural specialists—when they dig in, they quickly become expert," says Laurent Mottron, a psychiatrist at the University of Montreal.
Researchers also may have trouble getting a full picture of autism in society. According to Patricia Howlin, a psychologist at the Institute of Psychiatry at King's College London, traditional studies of individuals with autism are often based on people who have severe deficits and are referred to psychologists. But people with autism who have less severe deficits may be understudied, Howlin says.
Left hemisphere damage
Even so, the science behind savantism is becoming clearer, Marsa reports. Some research suggests that injuries in utero or in infancy to the brain's left hemisphere trigger an increase in activity in the right hemisphere, which is associated with certain features of artistic expression and creative thinking.
For instance, Bruce Miller, a neuroscientist at the University of California-San Francisco, scanned the brains of 12 patients with frontotemporal dementia (FTD), a type of dementia that primarily targets the left hemisphere of the brain, who developed an interest in art and artistic skills as their disease progressed.
The team theorized that the damage to the left hemisphere of the patients' brains unlocked dormant abilities in the right hemisphere that resulted in new kinds of creative thinking.
Miller's team compared the scans of elderly patients with FTD to scans of a young person believed to be an autistic savant and found similarities: the savant also had a loss of function in the left temporal lobe and heightened activity in the brain's right hemisphere.
More emerging research on families of savants has found that there may also be a genetic component to the condition. Some child prodigies were diagnosed with autism themselves when they were younger but stopped fitting the criteria as they grew older. And prodigies are more likely to have a close family member with autism.
"It means that the two conditions may have a common genetic root," says researcher Joanne Ruthsatz of The Ohio State University at Mansfield (Marsa, Atlantic, 1/15).