THE other week I was working in my garage office when my 14-year-old daughter, Olivia, came in to tell me about Charles Darwin. Did I know that he discovered the theory of evolution after studying finches on the Galápagos Islands? I was steeped in what felt like the 37th draft of my new book, which is on the development of scientific ideas, and she was proud to contribute this tidbit of history that she had just learned in class.

How We Are Judged by Our Appearance

Facial appearance translates to judgments of character.

We all know that looks matter. What most of us don’t understand is just how much looks matter, and how difficult it is for us to ignore a person’s appearance when making a social judgment. I’m not talking just about romantic relationships, I’m talking about all our human interactions. And by appearance, I’m not speaking simply of the “beauty,” dimension, but also of many other qualities of one’s appearance.

In all our perceptions, from vision to hearing, to the pictures we build of people’s character, our unconscious mind starts from whatever objective data is available to us – usually spotty – and helps to shape and construct the more complete picture we consciously perceive. In order to offer us this more complete picture, our unconscious employs clever tricks and educated guessing to fill in some blanks. In our perception of people, and their perceptions of us, the hidden, subliminal mind takes limited data, and creates a picture that seems clear and real, but is actually built largely on unconscious inferences that are made employing factors such as a person’s body language, voice, clothing, appearance, and social category. In earlier blog entries I’ve talked about body language and voice. Here I will focus on the important subliminal influence of a person’s facial appearance.

The arena in which facial appearance has been studied the most is politics – and an examination of that is especially appropriate in this election year. But the voting arena is also a good area to study the effects of appearance more generally, because many of our social decisions essentially amount to a vote: whom do we hire, whom do we date, whom do we trust? As in those instances, when we vote for a political candidate, we like to think we are examining the person on his or her merits, not on looks. But are we?

As I wrote in a recent Op Ed piece for the New York Times, recent research suggests that we may need to adopt a more cynical attitude. It turns out that a candidate’s appearance — not beauty, but a look of competence — can generate a significant vote swing. Furthermore, this effect is not only powerful but also subliminal. Few of us realize that appearance determines our vote, yet for a significant number of us, it may.

In one study, led by the political scientist Shawn W. Rosenberg of the University of California, Irvine, 140 volunteers were told that they were participating in a study of voting in which they would scrutinize candidates for Congress in three nearby districts. For each of the three races, the volunteers were shown two fliers presenting information about the candidates, including their party affiliations and their stances on several issues. Each flier also included a photo of the candidate.

In reality, the fliers had been concocted for the experiment. The photos were not of actual candidates but of models (all white males dressed in coat and tie) whose visages, in a prior survey with different volunteers, had been given either high or low marks with regard to perceived qualities like integrity, competence and leadership ability.

For each of the three races, the researchers arranged for half the subjects to see a flier in which the candidate with the more favorable appearance was pictured as the liberal Democrat, while the other half saw him pictured as the conservative Republican. That way, regardless of the split in party preference among the participants, the two candidates should receive about an equal number of votes if looks didn’t matter. Instead, the voting split about 60-40, with the majority favoring the candidate with the better visage.

A related series of studies, also led by Professor Rosenberg, showed that candidates could exert some control over the appearance factor. Researchers first recruited 210 volunteers to rate head-and-shoulder shots of hundreds of women in terms of how “able-looking” they were. From these ratings they determined that certain factors contribute to this appearance: for example, eyes with more curvature on the top than the bottom; hair that is short and parted on the side or combed back; a hairline that comes to a slight widow’s peak; a broad or round face; and a smile. Then they employed a Hollywood-style makeup artist and a photographer to use these criteria to create two images of each candidate, one more able-looking and one less. (A second study confirmed that the manipulations had the desired effect.)

Finally, the researchers recruited another set of volunteers to do the voting. Each candidate was presented in her “attractive” form to half the subjects, while her opponent was presented in her “unattractive” form. The other half of the subjects saw the same women running under the same party banners, but with the appearance variable reversed. On average, the candidates received 56 percent of the vote when portrayed by the better campaign photo, compared with 44 percent when portrayed by the unfavorable photograph — a vote swing of 12 percentage points.

In another series of studies, conducted at Princeton by the psychologists Alexander Todorov and Charles C. Ballew II, participants were presented with pairs of head-shot photos of the competing candidates in hundreds of actual Congressional and gubernatorial elections in the United States. After displaying a photo pair for just a quarter of a second, the researchers asked the participants to judge which candidate was more competent. (If a participant recognized a candidate, his response for that race was not counted.) These fleeting and uninformed impressions of competence turned out to correlate strongly with the actual election results. Over the hundreds of races tested, the more competent-looking candidate won the real-world election about 70 percent of the time.

The idea that appearance might be so influential is remarkable in light of the billions of dollars spent each election year to advertise candidates’ records, views and personal qualities. But what is really eye-opening is the idea similar hidden influences may exert a similar significant effect on all the other people choices we make in every day life.

Adapted from Subliminal: How Your Unconscious Mind Rules Your Behavior. Copyright 2012 by Leonard Mlodinow

How We Communicate Through Body Language

Nonverbal communication bestows advantages in both personal and business life.

As anyone who has ever been on the receiving end of a fellow driver’s display of the middle finger knows, nonverbal communication is sometimes quite obvious and conscious. But then there are those times when a significant other says “Don’t look at me like that,” and you respond, “Don’t look at you like what?” knowing full well the nature of the feelings you were so confident of having hidden. Or you might smack your lips and proclaim that your spouse’s scallop and cheddar casserole is yummy, but somehow still elicit the response, “What, you don’t like it?”

Scientists attach great importance to the human capacity for spoken language. But we also have a parallel track of nonverbal communication, which may reveal more than our carefully chosen words, and sometimes be at odds with them. Since much if not most of the nonverbal signaling and reading of signals is automatic and performed outside our conscious awareness and control, through our nonverbal cues we unwittingly communicate a great deal of information about ourselves and our state of mind. The gestures we make, the position in which we hold our bodies, the expressions we wear on our faces and the nonverbal qualities of our speech – all contribute to how others view us.

Nonverbal communication forms a social language that is in many ways richer and more fundamental than our words. Our nonverbal sensors are so powerful that just the movements associated with body language – that is, minus the actual bodies – are enough to engender within us the ability to accurately perceive emotion. For example, researchers made video clips of participants who had about a dozen small lights or illuminated patches attached at certain key positions on their bodies. The videos were made in light so dim that only the patches were visible. In these studies, when the participants stood still, the patches gave the impression of a meaningless collection of points. But when the participants stirred, observers were able to decode a surprising amount of information from the moving lights. They were able to judge the participants’ sex, and even the identity of people with whom they were familiar, from their gait alone. And when the participants were actors, mimes or dancers asked to move in a way that expressed the basic emotions, the observers had no trouble detecting the emotion portrayed.

We routinely participate in elaborate nonverbal exchanges even when we are not consciously aware of doing so. For example, in the case of casual contact with the opposite sex, I’d have been willing to bet a year’s pass to a Manhattan cinema that if a male pollster type approached a guy’s date while they were standing in line to buy a ticket at said theater, few of the fellows approached would be so insecure that they’d consciously feel threatened by the pollster. And yet, consider this experiment, conducted over two mild autumn weekend evenings in an “upper middle class” neighborhood in Manhattan. The subjects approached were all couples, yes, waiting in line to buy tickets to a movie.

The experimenters worked in teams of two. One team member discreetly observed from a short distance while the other approached the female of the couple and asked if she would be willing to answer a few survey questions. Some of the women were asked neutral questions such as “What is your favorite city and why?” Others were asked personal questions such as “What is your most embarrassing childhood memory?” The researchers were testing whether these more personal questions would be more threatening to the boyfriend, more invasive to his sense of intimate space. How did the boyfriends respond?

Unlike, say, a male baboon, who will start a fight when he sees another male sitting too close to a female in his group, the boyfriends didn’t do anything overtly aggressive. But they did display certain nonverbal cues. The scientists found that when the interviewer was nonthreatening – either a male who asked impersonal questions, or a female – the man in the couple tended to just hang out. But when the interviewer was a male asking personal questions, the boyfriend would subtly inject himself into the pow-wow, flashing what are called “tie-signs”, nonverbal cues meant to signal a connection with the woman. These male smoke signals include orienting himself toward his partner, and looking into her eyes as she interacted with the other man. It is doubtful that the men consciously felt the need to defend their relationship from the polite interviewer, but even though the tie-signs fell short of a baboon-like fist-in-the-face, they were an indication of the men’s inner primate pushing its way to the fore.

One of the most surprising forms of nonverbal communication is the way we automatically adjust the amount of time we spend looking into another’s eyes as a function of our relative social position. That might sound counterintuitive because some people like to look everyone in the eye, while others tend to always look elsewhere, whether they are speaking to a CEO or the guy dropping a pack of chicken thighs into their bag at the local grocery store. So how can gazing behavior be related to social dominance?

It is not your overall tendency to look at someone that is telling, but the way in which you adjust your behavior when you switch between the roles of listener and speaker. Psychologists have been able to characterize that behavior with a single quantitative measure, and the data they produce using that measure is striking. Here is how it works: take the percentage of time you spend looking into someone’s eyes while you are speaking, and divide it by the percentage spent looking at that same person’s eyes while you are listening.

For example, if, no matter who is talking, you spend the same amount of time looking away, your ratio would be 1.0. But if you tend to look away more often while you are speaking than when you are listening, your ratio will be less than 1.0. If you tend to look away less often when you are speaking than when you are listening, you have a ratio higher than one. That quotient, psychologists discovered, is a revealing statistic. It is called the “visual dominance ratio”. It reflects your position on the social dominance hierarchy relative to your conversation partner. A visual dominance ratio near 1.0, or larger, is characteristic of people with relatively high social dominance. A visual dominance ratio less than 1.00 is indicative of being lower on the dominance hierarchy. In other words, if your visual dominance ratio is around 1.0 or higher, you are probably the boss; if it is around 0.6, you are probably the bossed.

The unconscious mind provides us with many wonderful services, and performs many awesome feats, but I can’t help being impressed by this one. What is so striking about the data is not just that we subliminally adjust our gazing behavior to match our place on the hierarchy, but that we do it so consistently, and with numerical precision. Here is a sample of the data: when speaking to each other, ROTC officers exhibited ratios of 1.06, while ROTC cadets speaking to officers had ratios of 0.61; undergraduates in an introductory psychology course scored 0.92 when talking to a person they believed to be a high school senior who did not plan to go to college, but 0.59 when talking to a person they believed to be a college chemistry honor student accepted into a prestigious medical school; expert men speaking to women about a subject in their own field scored 0.98, while men talking to expert women about the women’s field, 0.61; expert women speaking to non-expert men scored 1.04, non-expert women speaking to expert men scored 0.54. These studies were all performed on Americans. The numbers probably vary with culture, but the phenomenon probably doesn’t.

Whatever your culture, since people unconsciously detect these signals, it stands to reason one can also adjust the impression one makes by consciously looking at or away from a conversation partner. For example, when applying for a job, talking to your boss, or negotiating a business deal, it might be advantageous to signal a certain level of submission – but how much would depend on the circumstances. In a job interview, if the job requires great leadership ability, a display of too much submissiveness would be a bad strategy. But if the interviewer seemed very insecure, a pleasing display of just the right amount of submissiveness could be very reassuring, and incline that person in the applicant’s favor. A very successful Hollywood agent I know once told me that he made a point to only negotiate over the telephone so as to avoid being influenced – or inadvertently revealing anything – through eye contact with the opposite party.

By the time children reach school age, there are some with full social calendars, while others spend their time shooting spitballs at the ceiling, and one of the major factors in social success, even at an early age, is a child’s sense of nonverbal cues. For example, in a study of 60 kindergartners, the children were asked to identify which of their classmates they’d prefer to sit with at story time, play a game with, or work with on a painting. The same children were judged on their ability to name the emotions exhibited in twelve photographs of adults and children with differing facial expressions. The two measures proved to be related. That is, the researchers found a strong correlation between a child’s popularity and ability in reading others.

In adults, nonverbal ability bestows advantages in both personal and business life, and plays a significant role in the perception of a person’s warmth, credibility, and persuasive power. Though much of body language hasn’t yet been studied scientifically, the general consensus is that tensely folded arms mean you are closed to what someone is telling you, while if you like what you hear, you’ll likely adopt an open posture, and even lean forward a little. Moving your shoulders forward seems to signify disgust, despair or fear, and that maintaining a large interpersonal distance while you speak seems to signal low social stature. It’s probably true that assuming those different postures can have at least a subtle effect on how people perceive you, and that understanding what nonverbal cues mean can bring to your consciousness clues about people that otherwise only your unconscious may pick up.

Adapted from Subliminal: how your unconscious mind rules your behavior, copyright 2012 by Leonard Mlodinow

How We Are Judged by Our Voice in Dating and the Workplace

Your voice exerts an unconscious influence on how others judge you.

People spend a lot of time talking and thinking about how members of the opposite sex look, but very little time paying attention to how they sound. To our unconscious minds, however, voice is very important. Our genus Homo has been evolving for a couple million years. Brain evolution happens over many thousands or millions of years, but we’ve lived in civilized society for less than 1 percent of that time. That means that though we may pack our heads full of 21st century knowledge, the organ inside our skull is still a Stone-Age brain. We think of ourselves as a civilized species, but our brains are designed to meet the challenges of an earlier era. Among birds and many other animals voice seems to play a great role in meeting one of those demands — reproduction — and it seems to be similarly important in humans.

For example, women may disagree on whether they prefer dark-skinned men with beards, clean-shaven blonds, or men of any appearance sitting in the driver’s seat of a Lamborghini — but when asked to rate men they can hear but not see, women miraculously tend to agree: men with deeper voices are more attractive. Asked to guess the physical characteristics of the men whose voices they hear in such experiments, the women tend to associate low voices with men who are tall, muscular, and hairy-chested — traits commonly considered sexy. As for men, a group of scientists recently discovered they unconsciously adjust the pitch of their voices higher or lower in accordance with their assessment of where they stand on the dominance hierarchy with respect to possible competitors. In that experiment, which involved a couple hundred men in their twenties, each man was told he’d be competing with another man for a lunch date with an attractive woman in a nearby room. The competitor, it was explained, was a man in a third room.

Each contestant communicated with the woman via a digital video feed, but when he communicated with the other man, he could only hear him, and not see him. In reality, both the competitor and the women were confederates of the researchers, and followed a fixed script. Each man was asked to discuss — with both the woman and his competitor — the reasons he might be respected or admired by other men. Then, after pouring his heart out about his prowess on the basketball court, his potential for winning the Nobel Prize, or his recipe for asparagus quiche, the session was ended, and he was asked to answer some questions assessing himself, his competitor, and the woman. The subjects were then dismissed. There would, alas, be no winners anointed.

The researchers analyzed a tape recording of the male contestants’ voices, and scrutinized each man’s answers to the questionnaire. One issue the questionnaires probed was the contestant’s appraisal of his level of physical dominance as compared to that of his competitor. And they found that when the participants believed they were physically dominant compared to their competitor — that is, more powerful and aggressive — they lowered the pitch of their voices, and when they believed they were less dominant, they raised the pitch, all apparently without realizing what they were doing.

From the point of view of evolution, what’s interesting about all this is that a woman’s attraction to men with low voices is most pronounced when she is in the fertile phase of her ovulatory cycle. What’s more, not only do women’s voice preferences vary with the phases of their reproductive cycle, so do their voices — in their pitch and smoothness — and research indicates that the greater a woman’s risk of conception, the sexier men find her voice. As a result, that both women and men are especially attracted to each other’s voices during a woman’s fertile period. The obvious conclusion is that our voices act as subliminal advertisements for our sexuality. During a woman’s fertile phase, those ads flash brightly on both sides, tempting us to click the “buy” button when we are most likely to obtain not only a mate, but, for no extra (upfront) cost, also a child.

In the workplace, too, the quality of your voice can be a deciding factor in your degree of success. The pitch, timbre, volume, speed, and cadence of your voice, the speed with which you speak, and even the way you modulate pitch and loudness, are all hugely influential factors in how convincing you are, and how people judge your state of mind, and character.

Scientists have developed fascinating computer tools that allow them to determine the influence of voice alone, devoid of content. In one method they electronically scramble just enough syllables that the words cannot be deciphered. In another, they excise just the highest frequencies, which wreaks havoc with our ability to accurately identify consonants. Either way, the meaning is unintelligible while the feel of speech remains. Studies show that when people listen to such “content-free” speech, they still perceive the same impressions of the speaker and the same emotional content that they do in the unaltered speech. Why? Because as we are decoding the meaning of the utterances we call language, our minds are, in parallel, analyzing, judging, and being affected by, qualities of voice that have nothing to do with words.

In one experiment scientists created recordings of a couple dozen speakers answering the same two questions, one political, one personal: What is your opinion of college admissions designed to favor minority groups? and What would you do if you suddenly won or inherited a great sum of money? Then they created four additional versions of each answer by electronically raising and lowering the speakers’ pitch by 20 percent, and by quickening or slowing their speech rate by 30 percent. The resulting speech still sounded natural, and its acoustic properties remained within the normal range. But would the alterations affect listeners’ perceptions?

The researchers recruited dozens of volunteers to judge the speech samples. The judges each heard and rated just one version of each speaker’s voice, randomly chosen from among the original and altered recordings. Since the content of the speakers’ answers didn’t vary amongst the different versions, but the vocal qualities of their voice did, differences in the listeners’ assessments would be due to the influence of vocal qualities and not the content of the speech. The result: speakers with higher-pitched voices were judged to be less truthful, less emphatic, less potent, and more nervous than speakers with lower pitched voices. Also, slower-talking speakers were judged to be less truthful, less persuasive, and more passive than people who spoke faster. So fast-talking may be a cliché trait of a sleazy salesman, but chances are, a little speed-up will make you sound smarter and more convincing. And if two speakers utter exactly the same words, but one speaks a little faster and louder and with fewer pauses and greater variation in volume, that speaker will be judged to be more energetic, knowledgeable and intelligent.

Expressive speech, with modulation in pitch and volume, and a minimum of noticeable pauses, boosts credibility and enhances the impression of intelligence. Other studies show that, just as people signal the basic emotions through facial expression, we also do it through voice. Listeners instinctively detect that when we lower the usual pitch of our voice, we are sad, and when we raise it we are angry or fearful.

If voice makes such a huge impression, the key question becomes, to what extent can we consciously alter our voice? Consider the case of Margaret Hilda Roberts, who in 1959 was elected as a Conservative member of British parliament for north London. She had higher ambitions, but to those in her inner circle, her voice was an issue. “She had a schoolmarmish, very slightly bossy, slightly hectoring voice,” recalled Tim Bell, the mastermind of her party’s publicity campaigns. Her own publicity advisor Gordon Reese was more graphic. Her high notes, he said, were “dangerous to passing sparrows.” Proving that though her politics were fixed, her voice was pliable, Margaret Hilda Roberts took her confidants’ advice, lowered the pitch, and increased her social dominance. There is no way to measure exactly how much difference the change made, but she did pretty well for herself. After the Conservatives were defeated in 1974, Margaret Thatcher – she had married wealthy businessman Denis Thatcher in 1951 – became party leader and eventually prime minister.

Adapted from Subliminal: how your unconscious mind rules your behavior copyright 2012 by Leonard Mlodinow

Why a Touch Can Double Your Chances of Getting a Date

Touch is one of the most important forms of subliminal communication in both humans and other primates. In the following excerpt from my book, Subliminal, I describe its importance in social bonding… When I was in high school, the few times I gathered the courage to approach a girl, the experience felt like I was administering a ¬multiple-choice test and she kept answering, “None of the above.” I had more or less resigned myself to the fact that a boy who spent his free time reading books on non-Euclidean geometry was not likely to be voted “big man on campus.” Then one day when I was in the library looking for a math book, I took a wrong turn and stumbled upon a work whose title went something like How to Get a Date. I hadn’t realized people wrote instructional books on subjects like that. Questions raced through my mind: Didn’t the mere fact that I was interested in such a book mean it would never fulfill the promise of its title? Could a boy who’d rather talk about curved space-time than touchdown passes ever score himself? Was there really a bag of tricks?

The book emphasized that if a girl doesn’t know you very well—and that applied to every girl in my high school—you should not expect her to agree to a date, and you shouldn’t take the rejection personally. Instead, you should ignore the possibly enormous number of girls who turn you down and keep asking, because, even if the odds are low, the laws of mathematics say eventually your number will come up. Since mathematical laws are my kinds of laws, and I’ve always believed that persistence is a good life philosophy, I took the advice. I can’t say the results were statistically significant, but decades later, I was shocked to find that a group of French researchers essentially repeated the exercise the book had suggested. And they did it in a controlled scientific manner, achieving results that were statistically significant. Furthermore, to my surprise, they revealed a way I could have improved my chance of success.

French culture is known for many great attributes, some of which probably have nothing to do with food, wine, and romance. But regarding the latter, the French are thought to especially excel, and in the experiment in question, they literally made a science of it. The scene was a particularly sunny June day in a pedestrian zone in the city of Vannes, a medium-sized town on the Atlantic coast of Brittany, in the west of France. Over the course of that day, three young and handsome French men randomly approached 240 young women they spotted walking alone and propositioned each and every one of them. To each, they would utter exactly the same words: “Hello. My name’s Antoine. I just want to say that I think you’re really pretty. I have to go to work this afternoon but I wonder if you would give me your phone number. I’ll phone you later and we can have a drink together someplace.” If the woman refused, they’d say, “Too bad. It’s not my day. Have a nice afternoon.” And then they’d look for another young woman to approach. If the woman handed over her number, they’d tell her the proposition was all in the name of science, at which time, according to the scientists, most of the women laughed. The key to the experiment was this: with half the women they propositioned, the young men added a light one-second touch to the woman’s forearm. The other half received no touch.

The researchers were interested in whether the men would be more successful when they touched the women than when they didn’t. How important is touch as a social cue? Over the course of the day, the young men collected three dozen phone numbers. When they didn’t touch the women, they had a success rate of 10 percent; when they touched them, their success rate was 20 percent. That light one-second touch doubled their popularity. Why were the touched women twice as likely to agree to a date? Were they thinking, This Antoine is a good toucher—it’d probably be fun to knock down a bottle of Bordeaux with him some night at Bar de l’Océan? Probably not. But on the unconscious level, touch seems to impart a subliminal sense of caring and connection.

Unlike non¬Euclidean geometry, touch research has many obvious applications. For example, in an experiment involving eight servers and several hundred restaurant diners, the servers were trained to touch randomly selected customers briefly on the arm toward the end of the meal while asking if “everything was all right.” The servers received an average tip of about 14.5 percent from those they didn’t touch, but 17.5 percent from those they did. Another study found the same effect on tipping at a bar. And in another restaurant study, about 60 percent of diners took the server’s suggestion to order the special after being touched lightly on the forearm, compared with only about 40 percent of those who were not touched. Touching has been found to increase the fraction of single women in a nightclub who will accept an invitation to dance, the number of people agreeing to sign a petition, the chances that a college student will risk embarrassment by volunteering to go to the blackboard in a statistics class, the proportion of busy passersby in a mall willing to take ten minutes to fill out a survey form, the percentage of shoppers in a supermarket who purchase food they had sampled, and the odds that a bystander who had just provided someone with directions will help him pick up a bunch of computer disks he drops.

You might be skeptical of this. After all, some people recoil when a stranger touches them. And it is possible that some of the subjects in the studies I quoted did recoil but that their reactions were outweighed by the reactions of those who reacted positively. Remember, though, these were all very subtle touches, not gropes. In fact, in studies in which the touched person was later debriefed about the experience, typically less than one-third of the subjects were even aware that they had been touched.

So are touchy-feely people more successful at getting things done? There is no data on whether bosses who dole out the occasional pat on the head run a smoother operation, but a 2010 study by a group of researchers in Berkeley found a case in which a habit of congratulatory slaps-to-the-skull really is associated with successful group interactions. The Berkeley researchers studied the sport of basketball, which both requires extensive second-by¬second teamwork and is known for its elaborate language of touching. They found that the number of “fist bumps, high fives, chest bumps, leaping shoulder bumps, chest punches, head slaps, head grabs, low fives, high tens, half hugs, and team huddles” correlated significantly with the degree of cooperation among teammates, such as passing to those who are less closely defended, helping others escape defensive pressure by setting what are called “screens,” and otherwise displaying a reliance on a teammate at the expense of one’s own individual performance. The teams that touched the most cooperated the most, and won the most.

Touch seems to be such an important tool for enhancing social cooperation and affiliation that we have evolved a special physical route along which those subliminal feelings of social connection travel from skin to brain. That is, scientists have discovered a particular kind of nerve fiber in people’s skin—especially in the face and arms—that appears to have developed specifically to transmit the pleasantness of social touch. Those nerve fibers transmit their signal too slowly to be of much use in helping you do the things you normally associate with the sense of ¬touch: determining what is touching you and telling you, with some precision, where you were touched. “They won’t help you distinguish a pear from pumice or your cheek from your chin,” says the social neuroscientist pioneer Ralph Adolphs. “But they are connected directly to areas of the brain such as the insular cortex, which is associated with emotion.”

To primatologists, the importance of touch is no surprise. Nonhuman primates touch each other extensively during grooming. And while grooming is ostensibly about hygiene, it would take only about ten minutes of grooming a day for an animal to stay clean. Instead, some species spend hours on it. Why? Remember those grooming cliques? In nonhuman primates, social grooming is important for maintaining social relationships. Touch is our most highly developed sense when we are born, and it remains a fundamental mode of communication throughout a baby’s first year and an important influence throughout a person’s life.

Excerpted from Subliminal: how your unconscious mind rules your behavior copyright 2012 by Leonard Mlodinow