Touch: The Science of Hand, Heart and Mind - Hardcover

Linden, David J.

Hardcover

ISBN 10: 0241184037 ISBN 13: 9780241184035

Publisher: Viking, 2015

Synopsis

David J. Linden, a Johns Hopkins neuroscientist and the bestselling author of The Compass of Pleasure, presents an engaging and fascinating examination of how the interface between our sense of touch and our emotional responses affects our social interactions as well as our general health and development. Accessible in its wit and clarity, Touch explores scientific advances in the understanding of touch that help explain our sense of self and our experience of the world. From skin to nerves to brain, the organization of the body's touch circuits powerfully influences our lives-affecting everything from consumer choice to sexual intercourse, tool use to the origins of language, chronic pain to healing. Interpersonal touch is crucial to social bonding and individual development. Linden lucidly explains how sensory and emotional context work together to distinguish between perceptions of what feels good and what feels bad. Linking biology and behavioral science, Linden offers an entertaining and enlightening answer to how we feel in every sense of the word.

About this title

About the Author:

David J. Linden is a professor of neuroscience at the Johns Hopkins University School of Medicine and the New York Times bestselling author of The Compass of Pleasure and The Accidental Mind. He lives in Baltimore, Maryland, with his two children.

Excerpt. © Reprinted by permission. All rights reserved.:

PROLOGUE

Malibu, Summer 1975

We’re eight teenage campers huddled around a fire ring, late at night. Piled up like puppies, spilling over rocks and stumps and the dusty bare dirt of the Santa Monica mountains, we smell of black sage and acorns and unwashed T-shirts. With no adults in sight and the soft cover of darkness, we give voice to our innermost pubescent thoughts.

“Your turn, Sam.”

“Okay . . . this is for Caroline. Would you rather give an open-mouth kiss to the camp director or eat a live cockroach?”

Our voices rise in a disgusted, delighted Greek chorus, “Eeeeeeeeeeeew!”

“You’re so gross, Sam. I’m not answering that one.”

“But you have to. Those are the rules.”

“No way, you pervert.”

“You’re so prickly. I didn’t mean to hurt your feelings.”

“Yeah, right.”

“Okay, here’s a clean one. Would you rather die of cold in Antarctica or heat in the Sahara Desert?”

“I’m not allowed to bring a parka to Antarctica?”

“No, you’re naked.”

“Then I choose the desert. I want to go out with a good tan.”

Good-natured howling erupts. Caroline raises her arm and shimmies, vamping it up.

Sam smiles. “You’re so vain. And . . . I’ve gotta go.” Everyone knows that this is bogus. It’s obvious that he’s crazy about Caroline.

“No, you don’t, you slippery sonofabitch. Now it’s my turn. You must give up all of your senses except one. Which do you pick to save?”

“Oh, man. That’s rough. I’d keep sight. Then, at least I could get around. Uh, no, hearing—I need my music. Shit. I dunno. That would just suck.”

“Yeah, it would.”

“I’m touched by your concern.”

“Bite me.”

Later, lying in my sleeping bag and mulling over this flirtatious banter, I was puzzled. Flush with hormones, we all hungered for interpersonal touch, for kisses and caresses and more. I was typical of this group, so consumed with the idea of holding and kissing a lovely dark-haired girl named Lorelei that I could barely speak. Touch was central to our obsessions and fantasies, yet none of us ever chose to preserve it when, in the nights that followed, Caroline’s question about losing one of our senses returned in the “Would you rather . . . ?” game. Did we simply not think the ramifications through? It’s certainly true that a bunch of horny sleep-deprived amped-up teenagers sitting around a campfire is not the ideal forum for contemplation. Or was it that we could easily imagine what it would be like to experience the loss of sight or hearing (we had all shut our eyes or plugged our ears), or even of taste or smell, yet none of us had ever actually been able to re-create the sensation of the loss of touch. Perhaps touch was woven so deeply into our sense of self that we could not truly imagine life without it. Years later when I read Lolita, I discovered that Vladimir Nabokov had, as usual, raised this very issue many years before: “It is strange that the tactile sense, which is so infinitely less precious to men than sight, becomes at critical moments our main, if not only, handle to reality.”

For Nabokov’s Humbert Humbert, touch was so infinitely precious an experience that even the merest tactile contact with his beloved Lolita aroused overwhelming passions. For all of us, the experience of touch is intrinsically emotional, and this is reflected in common expressions in English. Read the dialogue that opens this chapter and notice that phrases like “I’m touched by your concern” or “I didn’t mean to hurt your feelings” and texture metaphors like “you’re so prickly” or “that’s rough” or “you slippery sonofabitch” didn’t stand out at all. We are completely accustomed to describing a wide range of human emotions, actions, and personalities in terms of our skin senses:

“I was touched by her thoughtfulness.”

“It’s a sticky situation.”

“That’s enough of that coarse language.”

“That is one hairy problem.”

“He rubs me the wrong way.”

In everyday speech, the tactile is so entangled with the emotional that when we encounter someone who is emotionally clumsy, we call him tactless: Literally, he lacks touch.

This may seem like a silly question, but it’s not: Why are emotions called feelings and not sightings or smellings? Do touch metaphors really tell us something about the skin senses and their relationship to human cognition, or are they merely a common usage of present-day English? In fact, the constructions “I’m touched” to mean “I’m emotionally affected” and “my feelings” to mean “my tender emotions” have been in use in the language since at least the late thirteenth century. And such expressions are not unique to English, or even the Indo-European language group, as they are found in tongues as diverse as Basque and Chinese.

People who are blind or deaf from birth will for the most part develop normal bodies and brains (apart from the visual or auditory areas) and can live rich and fruitful lives. But deprive a newborn of social touch, as occurred in grossly understaffed Romanian orphanages in the 1980s and 1990s, and a disaster unfolds: Growth is slowed, compulsive rocking and other self-soothing behaviors emerge, and, if not rectified, emergent disorders of mood, cognition, and self-control can persist through adulthood. Fortunately, even a relatively minor intervention—an hour per day of touch and limb manipulation from a caregiver—can reverse this terrible course if applied early in life. Touch is not optional for human development. We have the longest childhoods of any animal—there is no other creature whose five-year-old offspring cannot live independently. If our long childhoods are not filled with touch, particularly loving, interpersonal touch, the consequences are dramatic.

The critical role of touch in early development has not always been appreciated. Child-rearing advice of the 1920s from the psychologist John B. Watson (the founder of the psychological movement called behaviorism) cautioned parents about spoiling their children with physical affection: “Let your behavior always be objective and kindly firm. Never hug and kiss them. Never let them sit on your lap. If you must, kiss them once on the forehead when they say goodnight. Shake hands with them in the morning. Give them a pat on the head if they have made an extraordinarily good job of a difficult task.”1

While most parents today do not restrict contact with their children to an occasional pat on the head, it’s a different story outside the family. In our zeal to protect kids from sexual predators, we have promoted no-touch policies for teachers, coaches, and other supervisory adults that, while well meaning, have the inadvertent effect of adding to the touch deprivation of our children. As these kids have grown up in a touch-phobic environment and propagated these fears to their own children, our society as a whole has become further impoverished.

You may ask, “Okay, I understand that kids are sensitive, but once we’ve become adults, why does it matter if we’re touch-deprived? This touchy-feely stuff is for hippies and time wasters. Just squirt out another glob of hand sanitizer (with that deeply satisfying blorp sound) and get back to work.” The answer is that interpersonal touch is a crucial form of social glue. It can bind sexual partners into lasting couples. It reinforces bonds between parents and their children and between siblings. It connects people in the community and in the workplace, fostering emotions of gratitude, sympathy, and trust. People who are gently touched by a server in a restaurant tend to leave larger tips. Doctors who touch their patients are rated as more caring, and their patients have reduced stress-hormone levels and better medical outcomes. Even people with clipboards at the mall are more likely to get you to sign their petitions or take their surveys if they touch your arm lightly.

The main point of this book is not merely to argue that touch is good or even that touch is important. Rather, it’s to explain that the particular organization of our body’s touch circuits, from skin to nerves to brain, is a weird, complex, and often counterintuitive system, and the specifics of its organization powerfully influence our lives. From consumer choice to sexual intercourse, from tool use to chronic pain to the process of healing, the genes, cells, and neural circuits involved in the sense of touch have been crucial to creating our unique human experience.

The transcendence of touch resides in the details, and, of course, these have been sculpted over the course of millions of years of evolution. They’re in the dual-function receptors in our skin that make mint feel cool or chili peppers hot. They’re in the dedicated nerve fibers in our skin that predispose us to like a soft caress (but only if it moves at the proper speed across the skin). And they’re in the brain’s specialized centers for emotional touch, without which an orgasm would seem more like a sneeze—convulsive, but not compelling. And lest we begin to think that everything’s hardwired and predetermined, these same emotional touch centers are neural crossroads where sensation and expectation collide, allowing for powerful effects of life history, culture, and context. Activity in these brain regions determines whether a given touch will feel emotionally positive or negative, depending upon the context in which it occurs. Imagine a caress from your romantic partner during a sweet, quiet connected time versus one that is administered right after he or she has said something deeply offensive. Similarly, these regions are where the neural signals engaged by the placebo effect, hypnotic suggestion, or even mere anticipation can act to dull or enhance pain. There is, in fact, no pure touch sensation, for by the time we have perceived a touch, it has been blended with other sensory input, plans for action, expectations, and a healthy dose of emotion. The good news is that these processes are no longer entirely mysterious. Recent years have seen an explosion in our scientific understanding of touch, revealing new ideas that help explain our sense of self and our experience of the world. So let’s dive in. The water’s not so cold once you get used to it. It will feel great.

CHAPTER ONE

THE SKIN IS A SOCIAL ORGAN

Warsaw, 1915

Solomon Asch was brimming with excitement. At the age of seven he had been allowed to stay up past his usual bedtime for his first Passover Seder. In the warm glow of the candles, he watched his grandmother pour an extra glass of wine that didn’t match a place setting.

“Who’s that glass for?” Solomon asked.

“It’s for the prophet Elijah,” explained an uncle.

“Will he really come inside and have some wine?”

“Certainly,” the uncle replied. “You just watch when the time comes, and we open the door to let him in.”

The extended family gathered around the table and read from the Haggadah, which tells the story of the Jews’ liberation from slavery in Egypt in the time of Moses. Following the teachings of the Talmud, prayers were intoned, wine was drunk, parsley was dipped in salt water, and a festive meal was consumed while reclining in the manner of free people of the ancient world. After the meal, as tradition dictates, the front door was opened to admit the prophet. A moment later, Solomon, primed with expectation and inspired by the Passover ritual, saw the meniscus in the wineglass drop just a bit, as if Elijah had taken a single sip before slipping out the door to visit other Jewish families.

Figure 1.1 Solomon Asch, a leader in the fields of social and Gestalt psychology. This photo was taken in the 1950s, when Asch was a professor in the department of psychology at Swarthmore College. He died in 1996, at the age of eighty-eight. Used with permission of the Friends Historical Library at Swarthmore College.

Solomon Asch emigrated with his family to New York City at the age of thirteen and soon learned English by reading the novels of Charles Dickens. As he grew older, he became fascinated with psychology, particularly social psychology, and earned his doctorate in that field in 1932 at Columbia University (figure 1.1). Years later he credited his interest in the field to his experience on that boyhood Passover night. How could the collective faith of the Seder celebrants lead him to believe in something like the prophet’s sip of wine, which was demonstrably impossible? This was not just an academic question. With the rise of Hitler and Nazism in Europe, Asch became particularly concerned with two related sociopolitical questions that would hold his attention throughout his career: How can the social world shape our beliefs in the face of clear contradictory evidence? And how do we come to form rapid decisions about another’s character? He wrote, “We look at a person and immediately a certain impression of his character forms in us. A glance, a few spoken words are sufficient to tell us a story about a highly complex matter. We know that such impressions form with remarkable rapidity and with great ease. Subsequent observation may enrich or upset our first view, but we can no more prevent its rapid growth than we can avoid perceiving a given visual object or hearing a melody.”1

Asch wanted to know if there were underlying principles that guided this quick formation of character impressions. After all, everyone we encounter presents us with an array of diverse characteristics. One person is courageous, intelligent, with a ready sense of humor, and swift in his movements, but he is also serious, energetic, patient, and polite. Another is slow, deliberate, and serious, but has a fast temper when provoked. How do such perceived characteristics come together to form an overall impression of an individual and enable us to extrapolate and predict his behavior in various circumstances? Does each separate characteristic join together in a whole to form our perception, or does one particular characteristic, or a small cluster of them, dominate our overall impression? Crucially, how do these processes play out for public figures like Hitler, Churchill, or Roosevelt, with whom few people interacted directly?

In 1943, midway through World War II, Asch devised an experiment to begin to address these questions. He recruited subjects—mostly young women during these wartime years—from undergraduate psychology classes at various universities in New York City, such as Brooklyn College and Hunter College. “I shall read to you a number of characteristics that belong to a particular person,” he told one assembled group. “Please listen to them carefully and try to form an impression of the kind of person described. You will later be asked to write a brief characterization of the person in just a few sentences. I will read the list slowly and will repeat it once: Intelligent . . . skillful . . . industrious . . . cold . . . determined . . . practical . . . cautious.” A second group heard the same list with a single substitution: “cold” was changed to “warm.” A sample response from ...

About this edition

• Publisher: Viking
• Publication date: 2015
• ISBN 10: 0241184037
• ISBN 13: 9780241184035
• Binding: Hardcover
• Edition number: 1
• Number of pages: 261