WEDNESDAY, Feb. 2 (HealthDay News) -- People with high-functioning autism have difficulty understanding others' intentions, new research shows.
This lack of understanding tends to make adults with autism, even those with high IQs, judge others more harshly, which may pose problems in forming and maintaining relationships, the study found.
Researchers from Massachusetts Institute of Technology asked 13 people with high-functioning autism, such as Asperger's syndrome, and a mean IQ of 120, as well as 13 neurologically normal adults to answer questions about moral quandaries in which a person meant well but ended up doing harm.
In one example, someone intended to put sugar in a friend's coffee, but it turned out to be poison. In another, two friends are kayaking in jellyfish-infested ocean waters. One friend had just read that the jellyfish were harmless and suggested they go for a swim. But then the other was stung and died.
People with autism came down harder on the person whose actions caused the harm, while those without autism put more emphasis on the person's good intentions.
"Adults with an autism spectrum disorder were less likely to take that intention information into account than a neurotypical person. They were more likely to make a harsh judgment of that person and less likely to forgive," said study co-author Liane Young, a postdoctoral associate at MIT.
The findings are reported in the Jan. 31 online issue of the Proceedings of the National Academy of Sciences.
Every day we have to make judgments about other's intentions, whether deciding how upset to get about an insensitive remark or a co-worker's slip-up.
"It's really important to be able to think about people's thoughts, beliefs and intentions, not only to make moral judgments but to figure out what they are doing and why," Young said. "To really understand people, it's important to know what they are thinking and intending."
The ability to discern other's intentions, desires and beliefs is called "theory of mind" and typically develops at about age 4 or 5, according to the study.
In a classic example, a child is shown two dolls, "Sally" and "Anne." The experimenter puts on a skit in which Sally puts a marble in a basket. While Sally isn't looking, Anne moves the marble from the basket to a box. The experimenter asks the child where Sally will look for the marble when she returns.
Knowing that Sally will look in the basket requires understanding that others have beliefs that may differ from our own.
Previous studies have shown that children with autism develop this ability later than other children, if ever, Young said.
But what's been difficult from a research perspective is that adults with high-functioning autism develop means of compensating for their social difficulties and would almost certainly be able to figure out the question involving the dolls, said Clara Lajonchere, vice president of clinical programs at Autism Speaks.
Researchers have had more difficulty assessing the more complex, nuanced skills required in making social judgments, something this study does well, Lajonchere said.
"The individuals with ASD [autism spectrum disorder] weighted outcome more highly than intention," Lajonchere said. "The ASD group did not reliably judge accidental versus intentional harm."
Yet, in many ways, people with and without autism were fairly similar. Given other scenarios, such as having bad intentions and causing harm, or having bad intentions but inadvertently having a good outcome, both group's answers were similar.
And there isn't necessarily a right or wrong answer to how readily we should forgive or give another the benefit of the doubt when they've caused harm to someone else. Even those without autism vary greatly in this capacity, Young said.
The U.S. National Institutes of Health has more on autism.