People with autism are more likely than others to be fooled by a magic trick that relies on social manipulation in order to deceive.
The results came as a surprise to the researchers, who hypothesized that people with autism would be less likely to pay attention to social cues, and thus less likely to be taken in by the trick.
The study focused on a trick known as the vanishing-ball illusion. In this illusion, a magician throws a ball in the air a few times. On the last throw, he merely pretends to throw it, making a tossing motion and looking upwards while the ball remains concealed in his hand. To onlookers, the ball appears to vanish in midair.
The trick works, studies of observers have shown, because of social cues — the audience watches the magician's face, and will later claim they “saw” the ball leave his hand. People with autism are known for having trouble interpreting social cues, so the researchers said they expected autistic individuals to watch the ball, rather than the magician's face, and thus have a better idea of what really happened.
In the experiment, 15 teenagers and young adults with an autism spectrum disorder, and 16 without autism, watched a video of the vanishing-ball illusion. They were asked to mark where they last saw the ball on a still image of the magician. The last place it appeared was in the magician's hand, but in other studies, many people have marked a position higher up, and say that he threw the ball.
People with autism were much more likely than others to think the magician had thrown the ball. This may be because the people in the study who had autism were all students at a special college for those with the condition, where they would have been taught to use social cues, said study researcher Gustav Kuhn, of Brunel University in the United Kingdom.
When he examined where their eyes had looked, Kuhn found, like people without the condition, they looked first at the magician's face — but their eyes took longer to fix there. They also had more trouble fixing their eyes on the ball.
“What we suggest is that individuals with autism have particular problems in allocating attention to the right place at the right time,” Kuhn said. This may cause trouble in social situations, when you have to be able to pay attention to the right thing at the right time.
Kuhn said he would like to repeat the experiment in children with autism, who may not yet have been educated in social cues, to see if they are also taken in by the illusion.
The results were published in the October issue of the journal Psychological Science.