Autism explained by weaker brain links
10 April 2006
UCL (University College London) scientists have found the reason why individuals with Asperger's Syndrome spend less time paying attention to others - weaker connections between brain areas mean that they benefit less from doing so.
According to research published in the journal Neuroimage, the key impairments associated with autism - including a severe lack of social skills and an inability to relate to other people - may be caused by poor communication between brain areas, rather than abnormalities in brain areas as had previously been suggested.
Dr Geoff Bird, at the UCL Institute of Cognitive Neuroscience, said: "The standard view of social problems in Asperger's Syndrome is that there is a problem in the part of the brain that processes faces. Our research suggests that this not the real problem: it seems to be that paying attention to faces doesn't lead to the normal increase in brain activity. This is because the face processing areas of the brain are not well connected to those parts of the brain that control attention i.e. the frontal and parietal regions.
"We all know that it is harder to pick a face out of a busy crowd, for instance, but when we do find the right face and pay attention to it we are easily able to tune-out all the other distractions and focus on that one face. It seems that, for people with Asperger's Syndrome, paying attention to a face is much harder to do and doesn't have the same effect."
16 volunteers with Asperger's Syndrome and above-average IQs took part in the brain scanning experiment. With four images on the screen - two of houses, two of faces - the volunteers were asked to concentrate on either the faces or houses and had to decide whether they were identical.
fMRI brain scans showed that there was a marked difference in brain activity between people with Asperger's Syndrome and a control group. In the control group, paying attention to pictures of faces caused a significant increase in brain activity. For the people with Asperger Syndrome, however, paying attention to faces made no impact at all on the brain, explaining their lack of interest in faces. People with Asperger's Syndrome showed the same brain reaction to houses as controls.
The work was funded by the Medical Research Council (MRC).
Notes for Editors:
1. Attention Does Not Modulate Neural Responses To Social Stimuli In Autism Spectrum Disorders appears on Neuroimage online on Monday 10th April 2006.
2. For further information please contact Alex Brew in the UCL press office on 020 7679 9726