Feeling Our Way Through Life

The outstretched paw of a bear, sculpted from white marble in 2nd century Rome, has been pawed so often by visitors to the J. Paul Getty Museum that it is deeply stained.

Rounded bellies of pregnant women are routinely patted by people without so much as a “Mother, may I?”

Car buyers giving the once-over to a potential vehicle run their hands along its fenders and even occasionally give the tires a swift kick.

“Please don’t touch?” We can’t help it.

Humans and primates are so touch-oriented that it is difficult for us to resist--even when stern signs, scowling docents or germ-o-phobic mommies warn us “look all you want but keep your $%&* hands off.”

The instinctive urge to experience the world through touch is part of a human drive to explore and interact with our environment. Hands and fingertips are the equivalent of other animals’ antennae, sensors that give us immediate information, tell us whether something is dangerous and aid us where eyes fail.

“Touch is the only sense that allows you to have direct experience,” says Robert La Motte, a professor of neurobiology at Yale University Medical School. “You can’t perceive softness without touching. . . . Micro-texture can only be detected by feel. You run your fingertips over the surface of a pan after you have washed it to make sure it’s clean. With your fingernail you can feel grading that is more disparate than a fraction of a micron. It is a way of confirming something is there.”

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Curiosity motivates most touching, prodding us to ignore social taboos and read “do not touch signs” as if they had an invisible footnote reading “except for you.”

“The vast majority of the public is so overwhelmed by seeing [art objects], especially sculpture, that they are almost unconscious of their arm reaching out,” says Jerry Podany, conservator of antiquities at the Getty Museum. “It’s a little more bold, but we have [a 4th century BC] throne, and people have actually sat in it.”

Getting dethroned by museum guards is a price some are willing to pay for what Podany calls a “trophy experience,” the right to brag that your backside touched (and fit!) an ancient Greek throne.

“Power touching” has elements of superstition, the idea that touching an icon or religious symbol will somehow transmit power. Witness the millions who kiss or touch the feet of St. Peter at the Basilica in Rome (the bronze is rubbed shiny from all the attention).

“I guess it’s a little like being touched by God,” La Motte says.

“Hedonic” touching, or touching for pleasure, is a ritual shared by everyone from the child who rubs a satin border of a blanket against her nose to men and women who dress in skin-stimulating fabrics such as chenille, silk and velvet.

These tactile feelings are mapped onto our brains from the very beginning of life. As babies, our sense of touch--far more developed than hearing or seeing--is the gateway through which the world is interpreted.

“When you watch a baby touch, you are watching the development of intelligence,” says Edward R. Perl, a professor of neurophysiology at the University of North Carolina at Chapel Hill. “The baby is programming those tactile feelings in neurons and in her cerebral cortex. When those neurons are activated, they signal the brain.”

Touch then interplays with the other senses to interpret our surroundings.

“Touch is a basic instinct that carries on through most of life,” says Stanley J. Bolanowski, a neuroscientist at Syracuse University’s Institute of Sensory Research. “It is the unifying force for all the other senses.”

The most sensitive touch receptors lie in our fingertips, lips and tongue, Bolanowski says. (Yes, he says, erogenous zones are sensitive too--but only to certain types of touch. That’s just one of the reasons uninvited groping is rarely welcome.)

When we run our fingers along the top of a freshly shaved head, the shell of a tortoise, the hood of a car, the sensation ignites a network of touch receptors. The receptors then fire off a flurry of pulses to the brain, the ensemble decoded as smooth, sharp, hot, cold or pressure. Research suggests that there are six types of tactile receptors (temperature, pain, vibration, pressure, flutter and buzz), each with its own channel. About 80% of skin receptors are devoted to sensing pain, a critical survival warning system.

But touch does more than satisfy curiosity or allow us to find a light switch in blackness: It changes and expands the brain.

“It is similar to wine tasting,” Bolanowski says. “You can train people to distinguish different vibratory rhythms and intensities of pressure, selectively adapting the brain. This was necessary to survive for our ancestors because it gives you an advantage over your fellow beings in managing your way through a dangerous environment.”

Even kicking a car’s tires demonstrates our “habit of tactilely interacting with our environment” for information. “We do get a feeling for how solid a structure is by whether it shakes and shimmies,” Perl says.

Indeed, asking people not to touch, as museums must do if art objects are to survive, is a little like saying “don’t breathe,” says Helen Fisher, professor of anthropology at Rutgers University.

Some museums have even surrendered to the natural impulse. At the Museum of African Art in Washington, D.C., the exhibits are placed behind plexiglass, safe from the reach of touchy-loos.