A virtual reality simulation of a journey on the London Underground has shown that paranoia is much more common among people who have no mental health problems than scientists had thought.

The research indicates that about a third of the general population often experience an exaggerated sense of persecution or threat.

The findings, by a team led by Daniel Freeman, of the Institute of Psychiatry at King’s College London, are considered authentic because they are based on people’s responses to a laboratory experiment, and not on answers to questionnaires, which can be misleading. In the study, published in the British Journal of Psychiatry, Dr Freeman’s team recruited 200 volunteers who were broadly representative of the general public.

All the participants were given virtual reality headsets that simulated the experience inside a London Underground carriage during a four-minute journey between two stops.

The carriage featured computer-generated figures known as avatars, who could be seen breathing, looking around and sometimes meeting the participants’ gaze. One avatar read a newspaper, and another would smile occasionally if looked at.

Though all the characters were designed to be neutral, showing neither overt hostility nor friendliness, the volunteers interpreted the same characters in very different ways.

The most common reaction was to find the simulated fellow passengers friendly or neutral, but almost 40 per cent of the participants reported feeling paranoid at least once during their journey.

A woman said that she felt threatened sexually by a male avatar, and others said that they suspected fellow passengers of being pickpockets, or potential bombers.

Dr Freeman said the results suggest that paranoia was a quite normal emotion: “In the past, only those with a severe mental illness were thought to experience paranoid thoughts, but now we know that this is simply not the case.”

Paranoid experiences were more common among people who were anxious or worried before starting the experiment, and among those with low self-esteem. “Paranoid thinking is a topic of national discussion given increasing public attention to threats such as terrorism,” Dr Freeman said.

“It sometimes seems as if the one thing that unites the diverse peoples of the world is our fear of one another.

“Worries about other people are so common that they seem to be an essential – if unwelcome – part of what it means to be human.”

Tunnel visions

“There was a guy spooking me out. Didn’t like his face. I’m sure he looked at me more than a couple of times”

“A girl kept moving her hand . . . like she was a pickpocket and would pass it to the person standing opposite her”

“Felt trapped between two men in the doorway. As a woman I’m a lot more suspicious of men. The guy opposite may have had sexual intent, manipulation or whatever”

“There’s something dodgy about one guy, like he was about to . . . assault someone, plant a bomb, be aggressive”

Source: Institute of Psychiatry study

Times Recommends

• 'Kelvin MacKenzie ate my paper'
• Cold, dark journeys of the lone wolf
• It’s too easy to blame dads