<font size="1" color="darkblue">Edited by - 瑞雪 on 2002/07/10 05:57:12</font>作者: 瑞雪 时间: 2002-7-10 05:55 标题: Re:耶魯大學近期的一個實驗 Experiment Offers Look Through Eyes of Autism
By JOHN O'NEIL
Enlisting Richard Burton and Elizabeth Taylor and a high-tech eye-tracking device developed for the military, researchers at Yale ran experiments that came closer than anything yet to offering a look at the world as seen through the eyes of people with autism.
In one experiment, described in the current issue of The American Journal of Psychiatry, the researchers compared the eye movements of a highly intelligent autistic adult and a control subject of the same age, sex and I.Q. as they watched the relentless emotional conflicts of "Who's Afraid of Virginia Woolf?"
What the experiment showed was that the two subjects were seeing the movie in starkly different ways. When Mr. Burton and Ms. Taylor, playing an alcoholic professor and his shrewish wife, confronted each other face to face, the gaze of the nonautistic adult swung intently between their eyes, while the autistic subjects looked back and forth, as well — but focused on the actors' mouths.
When Ms. Taylor flirted with George Segal, playing a young professor, as her husband lurked in the background, the gaze of the nonautistic adult described a triangle as he followed the expressions of all three. The autistic man never looked at Mr. Burton or anyone's eyes.
Dr. Ami Klin, a psychologist at the Yale Child Study Center who was the lead author of the study, said his team chose the movie because it presented complex social situations that involved just four characters and had few distracting inanimate objects.
To track eye movements, the researchers used a device made by Iscan of Burlington, Mass., said Warren Jones, a research associate who worked on the technical end of the experiment. He said eye-tracking technology had originally been developed largely with military funds to create a look-and-load system for fighter pilots.
The system in the Yale experiment looked like a baseball cap with two cameras attached. One camera, at cheek level, faces forward and records the field of view. An infrared camera on the bill points down to a piece of glass that hangs in front of the eyes and acts as a mirror, letting the cameras capture eye position changes without blocking the subject's view.
Dr. Klin said the device offered a tool to deal with one of the most frustrating research problems in studying autism, a little-understood brain disorder whose diagnosis has become increasingly common. Although autism affects a broad range of skills, the Yale researchers consider its central feature to be "a profound social disability," in Dr. Klin's words.
But when social tasks are broken down into discrete components suitable for research, autistic children can perform far better than in the hurly-burly of real social challenges like recess, he said.
The eye-tracking device allows researchers "to see what they see" while engaged in a more natural task, said Dr. Klin. "But we're less interested in what they understood than in how they searched for meaning," he said.
What the researchers saw in the "Virginia Woolf" study and in a larger follow-up trial — that autistic people tend to look at mouths or extraneous objects when nonautistic people look at eyes — fits in with other classic signs of autism like limited eye contact and difficulty in remembering faces.
Dr. Klin called it especially intriguing because normally developing infants learn, often as early as 3 months, to look at people's eyes instead of their mouths when searching for information about feelings and intentions.
Although autism is thought to affect brain development even before birth, in most children it is not diagnosed until age 3 or 4 or even later, when symptoms like language deficiencies or repetitive behaviors become evident. The Yale group has begun experiments to see whether eye-tracking tests could lead to earlier diagnoses because the best results come from intensive treatments that begin as soon as possible.
Dr. Klin said eye-tracking fitted into a developing theory about the delay in symptoms. The problem is not just abnormal brain structure, but a stunting of brain development because of the limited social input that comes from a focus on objects rather than people.
"We are," he said, "the sum of all our experiences."