Our Primal Need For Personal Space.
We all have an invisible, protective bubble around us. Personal space, a margin of safety, bad breath zone—whatever you call it, we have it constantly switched on like a force field. It comes in layers, some layers close to the skin like a bodysuit, others farther away like a quarantine tent. Elaborate networks in the brain monitor those protective bubbles and keep them clear of danger by subtly, or sometimes drastically, adjusting our actions. You walk through a cluttered room weaving effortlessly around furniture. A pigeon swoops past your head in the street, and you duck. You stand a little further from your boss than your friend, and much closer to your lover. Usually hidden under the surface of consciousness, occasionally rising into awareness, personal space affects every part of human experience.
In the 1950s, the director of the Zurich Zoo, Heini Hediger, saw the evolutionary roots of this behaviour in his careful studies of animals. Many animals have a territory based on external landmarks. Hediger noticed that most animals construct the second kind of territory that is egocentric, a bubble of space that moves as they move, and it serves a specific function. He called it an escape distance or a flight zone. When a wildebeest sees a potentially dangerous animal—a lion, or perhaps Hediger with a tape measure walking around the veld—it doesn’t simply run. This isn’t a simple stimulus-response proposition. The animal seems to make a geometric assessment. It remains calm until the threat enters a protected zone, and then the wildebeest move away and reinstates the flight zone. That escape distance is apparently consistent enough to measure it to the meter.
The flight zone is not the same as fear. It’s also not the same thing as running or flying away. It’s neither emotion nor a behaviour. It can certainly come with these properties, but the flight zone is a specific spatial computation that can proceed in the animal’s head in the absence of any obvious fear or escape. Animals can have a buffer even concerning other animals of the same species. One of Hediger’s most famous photographs was of a line of seagulls sitting on a log, spaced in such perfectly even increments that they looked almost like carved decorations.
In more recent decades, psychologists have conducted a vast number of studies around the human phenomenon of personal space. The most consistent finding out of this literature is that personal space extends with anxiety. If you score high on stress, or if the experimenter stresses you ahead of time—maybe you take a test and are told that you failed it—your personal space grows concerning other people. If you’re put at ease, or the experimenter flatters your self-esteem ahead of time, your personal space shrinks. In at least some studies, women have an especially large personal space when approached by men—presumably fueled by our culturally learned expectations. When tested at finer precision, personal space tends to stick out farther in front than at the sides or behind. When people are crowded together in the subway, and the balloon of personal space is compressed, you can see its intrinsic shape particularly well. If you could sneak around with a tape measure and record the average distance between the body parts of adjacent travellers, you would see an overall trend toward buffering the front of the face and especially the eyes. As always, the eyes are the epicentre of self-protection.
The most recent wave of research on personal space focuses on the brain mechanisms. Specific areas of the brain contain neurons that monitor the space around the body and track objects. These neurons are almost like radar, firing off signals when something looms close, their activity rising to a frenzied peak if the object touches. When those neurons become highly active, they feed directly into our movement control, subtly adjusting our movement or, in extreme cases, causing flinching or cringing. All this machinery impacts the rest of our lives: our sense of self, our ability to use tools, our culture and our social and emotional behavior—in other words, what it means to be human.
Credit: Michael Graziano for The Wall Street Journal, 5 January 2018. Dr Graziano is a professor of neuroscience and psychology at Princeton University. His new book is “The Spaces Between Us” (Oxford University Press).