How “personal space” may help shape modern medical science

I’m sure you’ve heard the term “personal space.” This concept refers to the area directly surrounding your body, which provides a comfort zone for conducting our everyday activities and interactions with others.

Our culture at least partially conditions our need or expectation for personal space. For example, in the Mediterranean area, people feel more comfortable getting closer to each other.

But personal space also has some very practical aspects beyond your feelings of having a comfort zone. For example, it guides where you put your hands when you reach out. It causes you to duck when objects come toward you. It also helps make you aware of the physical world around you.

And understanding personal space from a scientific view point has even broader implications…

Understanding how the brain perceives personal space

At first blush, the empty space close to your body might not “feel” different than the space outside your reach. But a wealth of research shows the brain perceives the empty space surrounding the body in a very unique way.

To explore this phenomena, researchers at the Karolinska Institute in Stockholm modified a well-known experiment called the “rubber hand illusion.”

In the original version of the experiment, the participant is shown a fake rubber hand while their own hand is hidden behind a screen. (This is not one of the experiments conducted by para-psychologist Peter Venkman [Bill Murray] in Ghostbusters!) The participant is then asked to stroke both the real (hidden) hand and the fake hand. After a few minutes of stroking both the fake and real hands, the participant’s brain comes to believe that the fake hand is not only real — but actually their own.

In the new study, 101 adults repeated the experiment, but, rather than actually touching or stroking the fake hand, they applied brush strokes in mid-air above the location of the fake hand.

As in the original experiment, participants started to believe that the fake hand is their own. They also started to sense what they said felt like a “force field” between the brush and the hand. The researchers found that the “force field” sensation reached as far as 15 inches above or beyond the false hand. The researchers called this zone our “peri-personal space.”

In the 1980s, Princeton researchers began to narrow down the part of the brain that perceives peri-personal space. In experiments with monkeys, they found the brain cells in the parietal and frontal lobes fired electrical impulses when an object came near the animals, not just when they were physically touched. It seems the human brain works the same way and has the ability to sense when something enters this personal space near the body.

During the 2000s, researchers continued to look at this “force field” phenomenon. By that time, researchers had already identified the specific brain cells that fired when an animal was touched…or when an object came near them. When researchers stimulated these brain cells directly, it caused the animal to exhibit blocking or ducking behaviors in coordinated ways.

Like a fluid, the force field around your body conforms to the contours of your body. It moves with your body and limbs, but never goes too far beyond them.

At least, not that we know yet.

George Lucas was onto something big

These experiments suggest that a force field around personal space aids in defense.

But, as I mentioned above, the concept of a force field around the body has much broader implications. Plus, understanding exactly how the mind perceives this invisible force field has many clinical applications.

For example, people who suffer cerebral strokes that affect the right rear parietal lobe of the brain can’t detect peri-personal spaces on the left sides of their bodies. And those that suffer left rear parietal lobe damage can’t detect peri-personal spaces on their right sides. These stroke patients can still perceive and process distant spaces, but they don’t have a sense of personal space on the affected side of the body. As we learn more about how the mind works, we may uncover a way to help stroke victims sense and even move their affected limbs.

And perhaps someday, scientists will be able to broaden the old rubber hand experiment to teach people (like Obi Wan Kenobe [Sir Alec Guinness] taught Luke Skywalker) how to extend “the Force” beyond our own bodies.

For now, though, we can all be more in tune with our personal space and the force field surrounding it by practicing mindfulness meditation. You can learn more about it — and other perceptual phenomena — in my books with Mike Jawer called Spiritual Anatomy of Emotion and Your Emotional Type.

I will tell you more about some of the quantum physical forces that may be behind these kinds of experiences later this month.

Source:

“The magnetic touch illusion: A perceptual correlate of visuo-tactile integration in peripersonal space,” Cognition October 2016; 155: 44–56