Autism linked to "supercharged" brain

From The Telegraph in the UK:

Children who develop autism have "supercharged" brains that are so clever and sensitive that they make everyday experiences utterly overwhelming, new research claims.

According to a theory developed by Swiss neuroscientists, the condition is not caused by a brain deficiency but by a system overload which causes the world to seem frightening and overly intense.

Husband and wife team Kamila and Henry Markram of the Swiss Federal Institute of Technology in Lausanne, believe the idea could explain the erratic nature of the condition.

"Our hypothesis is that autistic people perceive, feel and remember too much," Kamila Markram told the New Scientist.

Faced with this "intense world" , autistic infants withdraw, with serious consequences for their social and linguistic development, she added.

Repetitive behaviours such as rocking and head-banging, meanwhile, can be seen as an attempt to bring order and predictability to a "blaring world".

Most of the theories surrounding autism involve the idea of an underperforming brain but the Markrams believe the opposite is true with the brain being "supercharged".

Their research, which included studying their own son who is borderline autistic, is backed up by one of the most replicated findings in autism which is abnormal brain growth.

At birth the brains of autistic children are small or normal sized, but grow unusually quickly. By age two to three, when symptoms of autism occur, their brain volume is roughly 10 per cent larger than average.

The Markrams believe that autistic children suffer from "hypermemory" which lock them into certain compulsive routines and develop their savant skills.

"They build very strong memories," said Mrs Markram. "So strong that you establish a routine that you can't undo: you are stuck on a track."

Their theory chimes with the depiction of an autistic savant in the film Rain Man, starring Dustin Hoffman and Tom Cruise.

It also rings true with anecdotal evidence from autistic people.

"When I was younger, the school bell was like a dentist's drill hitting a nerve," said Temple Grandin, an animal scientist at Colorado State University in Fort Collins well known for being autistic.

"I think it's difficult for people to imagine a reality where sounds hurt your ears and a fluorescent light is like a discotheque."