To say that the brain is a complex organ is a tremendous
understatement. It is so complex, that
it is often hard to believe that it works so well for most people. At times, though, something goes wrong. We can get a lot of insight into the way that
brains function by studying both normal brains and abnormal ones.
A fascinating example of this work is presented in a paper
by Gustav Kuhn, Anastasia Kourkoulou and Susan Leekam in the October, 2010
issue of Psychological Science. These researchers compared normal people with
a group of people who have autism
spectrum disorder (abbreviated ASD).
These patients had a
high-functioning form of autism. Some of
these people used to be diagnosed with Asperger’s syndrome, which is no longer
an official diagnosis.
The researchers looked at how normal and ASD people
interpret a magic trick. They started
with an interesting hypothesis that the ASD people might actually be less
likely to see the trick as magic, because they often notice fine details in
people’s behavior.
The trick they used is called the vanishing ball
illusion. In this trick, a magician
throws a ball in the air twice. Each
time, he watches the ball as it goes up and down. On the third throw, he palms the ball and
makes a throwing motion. At the same
time, he looks up in the air again. Many
people claim to see a ball that then disappears.
In this study, people were told that they were going to see
a magic trick, and they had to figure out how it was done. They watched a video of the trick, and while
they were watching it, their eyes were being tracked.
The ASD people had trouble tracking the ball on each of the
first two throws, and so they tended to look at the magician’s face to see
where the ball went. On the third throw,
they looked at the magician’s face again, and so they used his gaze to decide
where the ball went on the last toss. They
were more likely than the normal people to claim to see the ball thrown on the
third toss, because they were generally focused on the magician’s face rather
than the ball.
It may seem surprising that the ASD people focused on the
magician’s face, because many studies of autism and related disorders has
focused on difficulties that people with autism have dealing with social
information. However, the evidence that
people with autism have difficulty with all social information is mixed.
The findings of this study suggest that people with ASD may
have difficulty switching their attention from one thing to another in a
situation. In a complex situation like
this, a person has to shift their attention between the magician’s face, his
hands, and the ball.
Think about how difficult it would be to figure out what is
going on the world if you have even a small difficulty in shifting your
attention from one thing to another. You
would always be a little off in your interpretation of what is going on around
you.
Obviously, ASD is a complex disorder, and it will take many
studies to pin down exactly what is going on.
But, these results demonstrate that difficulties with basic components
of cognition can have a huge impact on a person’s ability to comprehend the
world.