A new research paper by Northeastern professor Iris Berent demonstrates that the idea that the mind and body are separate and distinct rises naturally in people who are neurotypical and is not just the result of culture or environment.

People with autism are more likely to see the body and mind as one, according to the study in the Nov. 30 issue of the Proceedings of the National Academy of Sciences, which Berent conducted with Rachel Theodore, a professor from the University of Connecticut and a Northeastern graduate.

Berent, who has a Ph.D. in cognitive psychology, says the results have profound implications for how people think about science, religion and psychiatric disorders.

"It really affects how we think about everything," she says.

Berent called the distinction between body and mind dualism.

"Dualism is the belief that the mind is somehow separate from the body, that the body's physical but the mind is something else," she says.

"It turns out that even young children have these beliefs, and it doesn't look like something that is just in Western culture. We find it across cultures."

Berent says the paper is the first to show that a basic psychological mechanism that is critical for social interactions, called "theory of mind," is responsible for neurotypical people viewing the mind as separate from the body.

Theory of mind gives people the ability to recognize emotions, desires, beliefs and knowledge in themselves and other people and infer others' intentions.

"You kind of infer what the other person is thinking or feeling by watching their actions," Berent says.

Even young infants demonstrate theory of mind, she says.

"Three-month-olds, for instance, prefer a creature that helps another climb a hill to a creature that hinders the climber's action. This suggests that infants perceive creatures in terms of their goals, such as seeking to climb a hill, or helping/hindering others," Berent says.

Autistic people score lower on theory of mind social-cognitive skills, which is why they are often perceived as having social problems, Berent says. And these problems in "reading" the minds of others lead autistic people to view other people's minds as less distinct from their bodies.

In her study, researchers asked autistic and neurotypical people to imagine it would be possible to create a replica of their body in the future. Participants were asked which of a person's psychological characteristics would likely emerge in the replica—their thoughts or their actions.

"Autistic participants believed that thoughts would transfer to the replica more than neurotypicals," Berent says.

In a second experiment, participants were asked to imagine which of the person's traits will persist in the afterlife—after the body's demise. In this case, only neurotypical, but not autistic people, thought that the person's thoughts would persist.

"Autistic people tend to view thoughts as more strongly anchored in the body," Berent says.

"Neurotypicals, by contrast, are more dualists—they consider thoughts as separate from the body" and, therefore, they believe thoughts can persist without the body, in the afterlife—but not in the person's body and its replica, Berent says.

Dualism can be connected to the idea that there is life after death and that a soul exists separately from the body, she says.

But dualism also results in problems understanding science and treating psychiatric disorders, for which patients are often stigmatized and blamed even though the disorders originate in the brain, Berent says.

"This is the first study to link this thinking about bodies and minds to something that is core to the human psyche, to theory of mind."

It may be natural, but there's a cost to society and scientific understanding when body and mind are unyoked, Berent says.

Dualism is part of the reason people view mental health differently from what they consider physical health, she says.

But "science tells us that psychiatric disorders are diseases. Like all other diseases, they are part of the body."