Wednesday, April 13, 2005

Autism Spectrum Disorder and eye contact

Autistic children and adults are typically reluctant to make and keep eye contact with others - part of their general lack of social or emotional connection.A recent study suggests a basic reason for this: The eye contact overstimulates a part of the brain that processes fear and emotion, and people with autism learn to limit their eye- and face-tracking as a result.Using brain-scanning techniques, researchers also found that another part of the brain typically associated with processing facial information is underactive in autistic men and boys. Made physically uncomfortable by eye contact, the autistic subjects were not able to take in as much visual information about a face as the control subjects.In two studies at the Waisman Laboratory for Brain Imaging and Behavior at the University of Wisconsin, the subjects were placed in a magnetic-resonance-imaging scanner that recorded their brain reactions to photographs of faces expressing a variety of emotions. The autistic group consistently showed greater sensitivity than the control group to brain activity in the amygdala, where emotion generally is registered, and less activity in the fusiform gyrus, where the ability to read another’s facial expressions tends to reside.The studies also found that the longer the autistic group made eye contact with the facial images, the greater the electrical activity in the amygdala. The control group experienced no similar reaction.