People with traits associated with autism, particularly traits associated with mentalizing deficits, are less likely to believe in God, according to a new study.

The latest discovery strengthens the psychological theory that the likelihood of having religious belief largely depends on the ability for "theory of mind" or 'mentalization', a concept described as being able to imagine what others are thinking and to perceive and interpret behavior in terms of intentional mental states.

Because one of the trademarks of autism spectrum disorders, a group of developmental conditions marked by communication and social difficulties, is the inability to infer and respond to what other people are thinking, researchers speculated whether mentalizing deficits associated with the disorder would affect an individual's likelihood for religious belief.

People's beliefs in God are often defined by feelings of having a personal relationship with the deity, and prayer and worship often requires a person to interpret or sense what God could be thinking, therefore researchers predicted possessing traits associated with autism would decrease the likelihood of believing in a God.

Researchers writing in the journal PLoS ONE explained that because people affected by the disorder have difficulties grasping what others think, they will also have troubles intuitively conceptualize deities as intentional agents with mental states who anticipate and respond to human beliefs, desires and concerns, and thus will be less likely to believe in a God.

"Religious believers intuitively think of their deities as personified beings with mental states who anticipate and respond to human needs and actions. Therefore, mentalizing deficits would be expected to make religious belief less intuitive," lead researcher Ara Norenzayan of the University of British Columbia said in a statement.

University of British Columbia psychologists Ara Norenzayan and Will Gervais, along with their University of California, Davis colleague Kali H. Trzesniewski began their research with a study of 12 autistic children and 13 children without the disorder. Both the control and experimental group lived in the same neighborhood and were matched on characteristics like age, gender and family religion.

Their findings revealed that autistic children were only 11 percent as likely as their normally developing counterparts to say they strongly believed in God.

In another study on 327 Canadian college students, participants were asked to complete online questionnaires about the strength of their religious beliefs as well as a survey designed to place them on the autism spectrum.

The Autism Spectrum Quotient survey asked participants to agree or disagree with statements like "I find social situations easy," and "I prefer to do things the same way over and over again." 

Researchers found that participants with higher autism scores were less likely to believe in God.

Norenzayan and her colleagues had also conducted two studies in American adults, one with a nationwide sample of 706 participants and the other with 452 participants, and found, once again, that autistic traits decreased belief in a deity.

In both the adult studies, theory of mind of the ability to mentalize explained the differences between believers and nonbelievers.

Researchers noted that findings from all four studies were correlational, and did not prove that the inability to imagine other minds led to atheism or agnosticism.

They also cautioned that people may adopt religion for a combination of psychological and cultural reasons independent of theory of mind of mentalizing abilities.

"Several studies have recently shown a relation between mentalising and the belief in a personal god," said Uffe Schjødt of Aarhus University in Denmark, who found that regions of the brain important for mentalising are active when people pray, according to New Scientist. "Their finding that deficiencies in mentalising, as seen in people with autism, correlate with a decrease of such beliefs is hardly surprising, but it now finds support in solid empirical data."

Previous studies have also shown that analytical thinkers and men are also less likely to believe in a deity.