Short man syndrome really does exist, Oxford University academics have found, after a study showed feeling smaller makes people paranoid, distrustful and scared of others.

Scientists used virtual reality technology to reduce the height of volunteers travelling on a computer-simulated Tube train by 10in (25cm).

The experience of being shorter increased reports of negative feelings, such as being incompetent, dislikeable or inferior.

It also heightened levels of mistrust, fear and paranoia. Height-reduced participants were more likely to think someone else in the virtual train carriage was deliberately staring, thinking badly about them, or trying to cause distress.

Professor Daniel Freeman, who led the Medical Research Council-funded study, said: "Being tall is associated with greater career and relationship success.

"Height is taken to convey authority, and we feel taller when we feel more powerful. It is little wonder then that men and women tend to over-report their height.

"In this study we reduced people's height, which led to a striking consequence: people felt inferior and this caused them to feel overly mistrustful. This all happened in a virtual reality simulation, but we know that people behave in VR as they do in real life.

"It provides a key insight into paranoia, showing that people's excessive mistrust of others directly builds upon their own negative feelings about themselves.

“The important treatment implication for severe paranoia that we can take from this study is that if we help people to feel more self-confident then they will be less mistrustful.”

Participants in the study experienced the same simulated tube journey twice, once at their normal height and the second time from the perspective of someone 10in (25cm) shorter.

On both journeys, the other virtual passengers in the carriage were programmed to be "neutral" and not do anything to provoke feelings of fear or mistrust.

Generally the lowering of height was not consciously registered by the volunteers, but its effects were unmistakable.

"The results were very clear: lowering of height led to more negative evaluations of the self compared with others and greater levels of paranoia," said the scientists writing in the journal Psychiatry Research.

The findings were said to lend support to previous studies linking height and social status, and show how low self-esteem can lead to paranoid thoughts.

Professor Hugh Perry, who chairs the MRC Neurosciences and Mental Health Board, said: "For people whose lives are affected by paranoid thinking, this study provides useful insights on the role of height and how this can influence a person's sense of mistrust."

Online Editors