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People with autism don’t seem to experience a virtual reality illusion about their body that people who don’t have autism usually fall for.

Some autistic people view autism as a different way of seeing the world. Jane Aspell at Anglia Ruskin University in the UK and her team wondered if people with autism may perceive a particular illusion differently.

This illusion involves wearing virtual reality goggles that let you view your own body as if you are looking at someone else. Wearers of the goggles see this avatar being stroked on its back, at the same time as their own back is stroked in real life. This commonly makes people feel like they are starting to embody the virtual avatar, and their sense of where they are located shifts towards it.

Aspell’s team recreated this illusion for 51 volunteers, about half of whom had autism. Questionnaires afterwards found that the autistic participants weren’t susceptible to the illusion. This suggests that, in autism, “the way the brain is generating a sense of self is somehow different”, says Aspell.

Before the virtual reality task, the volunteers were asked to carry out a test that measured the size of the area surrounding them that they unconsciously saw as personal space. “Our sense of self doesn’t end at the skin – there’s a hazy bubble around us,” says Aspell. The volunteers with autism had a personal space about 10 centimetres smaller than those who didn’t have the condition.

Other work has shown people with autism are also ”, a similar scenario to the virtual body illusion that tricks people into feeling that a rubber hand is their own hand.

Read more: Virtual out-of-body experience reduces your fear of death