A scientifically determined distance can now be given for how much personal space we need after researchers investigated the relationship between anxiety and distance needed from threats. The scientists have put the limit of what they call “peripersonal space” surrounding the face at around 8 to 16 inches (between 20 and 40 centimeters).
The researchers, publishing in The Journal of Neuroscience, say that this personal space was previously thought of as a gradual boundary but has now been given “physical limits.”
The study also found that people with anxiety traits needed greater peripersonal space.
For their experiment, Drs. Chiara Sambo and Giandomenico Iannetti, from England’s University College London, recorded the study subjects’ blink reflexes – “defensive responses to potentially dangerous stimuli” at varying distances from their faces.
They then compared the reflex data with results from anxiety questionnaires.
One of these measured personality traits by asking people to rate themselves on a scale of one to four against statements of anxiety such as “I worry too much over something that really does not matter,” as well as statements of the opposite, for example, “I am a steady person.”
Another set of questions asked how study participants would feel in certain situations, again obtaining a rating of one to four. Example scenarios included “swimming while wearing a nose plug” and “being handcuffed for 15 minutes.”
People who scored highly on the anxiety test tended to react more strongly to stimuli 8 inches from their face than those who got low scores.
The researchers classified the more anxious people reacting more strongly to further-away stimuli as having a large “defensive peripersonal space.” In the study paper, the authors discuss a possible reason why anxiety created the need more personal space:
“In more anxious individuals, the ‘safety margin’ is located at a further distance from the body than in less anxious individuals.
This could be because these individuals perceive threatening stimuli as closer to their body than they actually are.”
Dr. Chiara Sambo put this another way, telling Medical News Today that the study found “more anxious individuals have a larger ‘defensive space,’ possibly because they overestimate the critical distance at which self-protective behaviors are required.”
The findings, Dr. Sambo added, are consistent with other work:
“Our findings extend previous research showing that anxious individuals exhibit enhanced sensitivity and vigilance towards threat-related stimuli in the environment.
They are also in line with characteristics of anxiety disorders, namely overestimation of threat, although our study was not conducted in a clinical population.”
The way in which the researchers tested participants’ blink reflexes was to apply an intense electrical stimulus to a specific nerve in the hand that caused them to blink – a reflex that is not under conscious control of the brain.
They monitored this reflex while a subject held their own hand at 4, 20, 40 and 60 centimeters from their face.
“The magnitude of the reflex,” the researchers say, “was used to determine how dangerous each stimulus was considered, and a larger response for stimuli further from the body indicated a larger defensive peripersonal space.”
The study concluded that there is a hard edge to people’s personal space, a well-defined kind of perimeter fence against threat – they found an “abrupt rather than a gradual increase” in the size of the hand-blink reflex as the hand got closer to the face.
The result that more anxious people responded to threats at a wider personal space “suggests that individuals differ in what they consider to be the critical distance at which a threatening stimulus requires more efficient defensive responses.”
The authors say this is because the more defensive hand-blink reflex “represents a ‘safety margin’ with the purpose of protecting our body from potentially dangerous stimuli.”
The scientists say they hope their findings can be used as a “test to link defensive behaviors to levels of anxiety.”
They believe this could be particularly useful for seeing how good people are at determining risks in certain jobs – fire, police and military personnel, for example, who encounter dangerous situations.