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A few months ago I was almost hit by a skateboarder. He was practicing a complicated maneuver that involved flinging himself down a set of concrete steps into a courtyard. I was coming up the same steps, distracted, and at the last instant I looked up and saw the looming blur.
A set of reflexes kicked in before I realized what was happening. Networks in my brain tried to save me from my own absent-mindedness. I found myself crouching into a quarter turn, my arms jerking around myself. The skateboarder zipped past, missing me by inches. A loose flap his T-shirt, which was about three sizes too large for him, brushed against my shoulder. He landed in a heap on the stone flagging below, his body in a protective curl, while the skateboard hit the ground twenty feet away.
He didn’t say anything, so I didn’t either. Just another Wednesday, I guess. I un-crouched myself and walked on. He collected his skateboard and flung himself down the stairs again.
I spent twenty years studying the brain mechanisms of personal space and bodily self-protection. When I first found myself studying that topic in the lab, I figured it would be interesting to specialists, but probably limited in scope. We back away, flinch, sometimes spread our hands to protect our faces. All very useful. In the grand scheme of humanity, so what? But as I studied the protective systems, I began to realize that I was pulling on a thread and the thread didn’t seem to have an end. It was connected to every part of the human experience, especially social interaction. Though we rarely face a case as dramatic or urgent as a flying skateboarder, we’re always computing and adjusting interpersonal distances, and we do it both to maintain a safety buffer and to play the social dance. Personal space is the ruler by which we measure out that social dance.
Except in extreme circumstances, we’re mostly unaware of our defensive systems. This hidden quality is why I didn’t understand them at first. Of course, if someone takes a swing at you or a wasp flies in your face, the reflexes are obvious. But at a subtler level, they’re always in operation. A constant simmer of activity in those neural pathways adjusts our behavior and keeps the body safe from danger and buffered from each other. That mechanism nuances every action we make. It forms an invisible cushion between us and the world, between people, a miniature portable territory that organizes how we interact with everything and everyone else.
Like the physical skin, personal space has been shaped by evolution over millions of years and has taken on quirky accouterments, many of which have floated free of any specific role in defending the body. I think of them as the feathers and horns of personal space. These features have morphed into signals that we use to influence each other’s behavior. Why do we expose our teeth as a gesture of friendliness? Why do we leak lubricant from our eyes in order to solicit comfort from each other? Why do we extend a hand, in effect showing that our protective space is opened up and a vulnerable part of the body is exposed, as a sign of non-aggression?
Personal space and defensive reflexes may have contributed to the evolution of smiling, laughing, crying, social cringing, standing tall, and many other familiar gestures. Mating requires reducing your defensive space. It’s not an accident that kissing the face and neck – putting one’s teeth on heavily defended parts of the body, the parts most vulnerable to predators – has evolved into a ritual for testing and confirming sexual acceptance. Even the evolution of tool use was probably significantly affected by personal space. To master the tool you must stretch your personal space around it. You can’t properly wield a hammer or a pencil otherwise. Nobody would ever pass a driving test if we couldn’t wrap our personal space around the edges of the car. If you examine almost any aspect of human life, you soon see how it may have been shaped by the requirements of personal space.
In this series of pieces, over the next months, I would like to share a few thoughts on personal space. I’ll touch on the history of how it was discovered, its impact on us as social animals, and my own work on its neuronal mechanisms in the brain. I hope these short pieces will show what I myself discovered – that the topic of personal space is surprisingly deep and surprisingly relevant to everyday life.
