FRIDAY, Dec. 18, 2009 (HealthDay News) -- The brains of autistic people are less active than expected when they're engaged in self-reflective thought, a finding that helps explain autism-related social difficulties, say British researchers.
Using functional MRI, they measured the brain activity of 66 males, half of whom had autism, while they were asked questions about their own or the Queen's thoughts, opinions,preferences, or physical characteristics.
The researchers were particularly interested in an area of the brain called the ventromedial prefrontal cortex, which is known to be active when people think about themselves.
In non-autistic volunteers, this part of the brain was more active when they were asked questions about themselves than when they were thinking about the Queen. But the response was equal when those with autism were asked about themselves and the Queen.
"This new study shows that within the autistic brain, regions that typically prefer self-relevant information make no distinction between thinking about the self or another person. This is strong evidence that in the autistic brain, processing itself is atypical," said Michael Lombardo of the Autism Research Centre at the University of Cambridge.
"Navigating social interactions with others requires keeping track of the relationship between oneself and others," he explained. "In some social situations it is important to notice that 'I am similar to you,' while in other situations it might be important to notice that 'I am different to you.' The atypical way the autistic brain treats self-relevant information as equivalent to information about others could derail a child's social development, particularly in understanding how they relate to the social world around them."
The study was published Dec. 14 in the journal Brain.
The U.S. National Institute of Neurological Disorders and Stroke has more about autism.