A new study has found that people with schizophrenia who experience paranoia tend to prefer significantly more personal space than others, and this physical cue could help clinicians detect symptoms that often go unspoken. Researchers suggest that measuring how close someone is comfortable standing to others may offer a simple and effective way to identify paranoia and predict social difficulties. The findings were published in the journal Molecular Psychiatry.
Paranoia is a common and distressing symptom in schizophrenia, often involving the belief that others intend to cause harm. It can be difficult to spot through conversation alone, especially as many individuals may hide or minimise their fears during interviews.
Adamantini Hatzipanayioti, PhD, a researcher from the University Hospital of Psychiatry and Psychotherapy in Switzerland, explained the study’s purpose. “The study’s motivation stemmed from the clinical challenge of detecting paranoia in individuals with schizophrenia. Paranoia, a core symptom of schizophrenia characterised by unfounded beliefs of threat or persecution, often goes undetected in clinical interviews.”
The research, which involved 92 patients and 52 healthy controls, demonstrated that individuals with paranoia consistently preferred to keep a larger distance from others. Personal space thresholds averaged around 2.3 metres in those with paranoia, compared to 1.17 metres in healthy participants. When asked to indicate the point at which they felt uncomfortable during interactions, participants with severe paranoia chose distances that were noticeably greater, especially when eye contact was involved. These findings suggest that social proximity can feel threatening, causing discomfort and stress in people with paranoid thoughts.
“Prior research from our team indicated that individuals with paranoia exhibit an abnormally enlarged personal space,” said Hatzipanayioti. “In the present study, we aimed to validate whether personal space could serve as a behavioural marker for paranoia, assess its physiological correlates, and determine whether these measures could predict long-term outcomes.”
The study confirmed that measuring personal space can serve as a diagnostic tool. A distance greater than 1.1 metres identified paranoia with 92% sensitivity, while a distance of 1.6 metres identified more severe paranoia with 87% sensitivity and 81% specificity. “Key findings revealed that paranoid schizophrenia patients maintained significantly larger personal space compared to both non-paranoid patients and healthy controls,” said Hatzipanayioti. “The personal space test is a brief, bedside behavioural tool that could enhance early identification of paranoia and be easily implemented in clinical settings.”
Stress responses recorded during the tasks provided further insight. People with more severe paranoia showed heightened physiological stress when others came too close, reinforcing the link between paranoid thinking and a strong need for distance. “Skin conductance responses showed that increased personal space was associated with high stress levels,” noted Hatzipanayioti. “Importantly, baseline stress levels predicted long-term functioning, suggesting that stress may mediate the relationship between paranoia and social impairment.”
While the study found that baseline levels of personal space and paranoia did not predict future outcomes directly, people who showed a reduction in personal space over six months tended to experience improvements in social functioning. “While personal space alone did not predict six-month functional outcome, individuals whose personal space decreased over time demonstrated greater recovery,” said Hatzipanayioti. “Additionally, targeting stress through interventions may play a key role in improving functional outcomes.”
The findings highlight a potential cycle in which paranoia increases personal space needs, leading to social withdrawal and reduced interaction. Over time, this can affect a person’s ability to form relationships and maintain employment. Clinicians are encouraged to be mindful of how physical space is navigated by patients and to consider this behaviour in treatment planning. “Maintaining enlarged personal space could also improve therapeutic rapport,” said Hatzipanayioti.
She added that their team has plans to build on the current findings. “Future plans include extending longitudinal studies to more precisely track personal space, stress, and social functioning. We also propose incorporating neuroimaging to investigate the neural circuitry underlying personal space regulation and exploring interventions that modulate personal space or reduce stress.”
While medication and illness duration were accounted for, the results point to personal space as a valuable measure of emotional state and social capacity. As mental health services continue to explore accessible support methods for people with schizophrenia, these behavioural cues may provide a practical route for earlier detection and more tailored treatment.
