When Robert Provine examined spectograms of different laughs—that is, their acoustic signatures—he took out the staccato bursts that we hear as “ha, ha, ha” or “tee, hee, hee.” These on average last about .75 seconds. In any typical laughter “bout,” there are three to four of these “calls.” What Provine found underlying those bursts was a deep sigh. Laughter is the primordial breathing technique, the first “take a deep breath” exhalation. When chimps and bonobos show the open-mouth play face, they are altering their fight/flight physiology to reduce the chances of aggression and opening up opportunities for play and affiliation.
GRUNTS, SNORTS, AND A SPACE OF ITS OWN
We have encountered some basic laughter facts—it is almost always social, it collapses the body into a state of relaxation, it is intertwined with breathing. We still, however, have not answered the simplest of questions: What is the meaning of a laugh? What unites the remarkable varieties of human laughter? Clues to understanding a category of expressive behavior—be it a sigh, a tongue protrusion, the eyebrow flash, or the blush—emerge when scientists seek principles that unite the varieties of behaviors within that category. We can thank Jo-Anne Bachorowski for this kind of painstaking work on the complex acoustics of human laughter.
As air moves through the human vocal apparatus, upon being pushed out by muscle contractions surrounding the lungs it is given a vibratory pattern through movements of the vocal folds. The speed with which the vocal folds vibrate gives the sound its pitch. These sounds are then given additional acoustic qualities, known as resonances and articulations, as they pass through the throat, delicate gymnastics of the human tongue, the opening of the mouth (for example, is it wide open, or are the teeth clenched?) and degree of opening in the nasal passage. Researchers then take these complex sounds, as represented in spectrograms, and extract a variety of different measures to arrive at an acoustic profile of a laugh, a sigh, a moan, a groan, or a tease. Measures include speech rate, pitch, loudness, pitch variability, and whether the sound rises or falls at the end.
Bachorowski was the first to put laughs through this complex form of acoustic analysis. She did so by recording the laughs of friends and strangers while watching Robin Williams, while playing amusing games together, or while simply talking casually. She has ruined her eyes in close-up analysis of thousands of laughs, and arrived at the beginnings of a laughter dictionary. There are cackles, hisses, breathy pants, snorts, grunts, and songlike laughs with mellifluous acoustic structure. Provine has found that women tend to laugh more than men, and Bachorowski’s work ups the gender ante: Men, pitiful apes that they are, are much more likely to snort and grunt than women.
Bachorowski then conducted microscopic analyses of the fundamental acoustics of laughs. This laborious work yielded three clues to the deep meaning of laughter, and why it emerged in human evolution. The first clue helps us to begin to make sense of the astounding varieties of laughter. Bachorowski has differentiated between what she calls voiced laughs, which have tone to them and involve vibrations of the vocal folds (chords), and unvoiced laughs, which do not. Voiced laughs sound like songs, rising and falling as they move through space. Other people perceive these laughs as invitations to friendship and camaraderie. Unvoiced laughs—hisses, snorts, grunts—are not perceived as such. Much as the language of smiles is divided into Duchenne and non-Duchenne smiles, there are voiced laughs of pleasure and unvoiced laughs not involving pleasure. In his remarkable meditation on laughter, The Book of Laughter and Forgetting, Milan Kundera writes about two kinds of laughs. The laugh of the devil denies the rational order of the world. The laugh of the angel affirms the beauty of things and brings lovers, friends, and comrades together in common purpose in an elevated state above the earthly ground. Voiced laughs are Kundera’s laughs of angels and unvoiced laughs those of the devil. Both are vital to the social contract.
Bachorowski made a second crucial discovery in analyses of how the laughs of individuals play off one another like the sounds of different instruments in an orchestra. The laughs of friends, as opposed to those of strangers, start out as separate vocalizations but quickly shift to become overlapping, intertwined sounds whose acoustic qualities mimic each other. Bachorowski deemed these laughter duets antiphonal laughter. This is the kind of laughter that unites people in affection. Friends, when responding to humor and levity, quickly find a common place in acoustic space for sharing laughter; their minds are united in two-to three-second periods of antiphonal laughter.
Finally, Bachorowski identified where laughs fall in acoustic space compared to consonants and vowels. Here a remarkable discovery: Laughs occupy a part of acoustic space that is different from vowel sounds like “ahhh” and “eee.” We may describe laughs in the written word as “ha, ha, ha” or “hee, hee, hee,” but in fact the acoustic structure of laughter is distinct from that of the vowels we use to represent this mysterious category of behavior. Certain regions of the human vocal apparatus produce the vowels and consonants that make up human speech, in which so much of human social life transpires. But there is another register of the human vocal apparatus, another form of output—laughter—with different origins and functions than human speech.
In light of Bachorowski’s discoveries, it is now assumed that laughter preceded language in human evolution, emerging in early protohuman form some four million years ago. This is significantly earlier than when humans started to put together vowels and consonants into phonemes, and those phonemes into words and sentences. Recent neuroscientific data on laughter, summarized by Willibald Ruch, one of the leading laughter scientists, yields a similar conclusion about the early appearance of human laughter in evolution. Ruch has synthesized numerous brain studies of laughter. Some focused on the brain correlates of pathological laughter. For example, people who suffer from a syndrome known as pseudobulbar affect will abruptly break into uncontrollable laughter in response to inappropriate stimuli—the tilt of a head, the movement of a hand, a trivial comment in a conversation. In other studies, laughter was observed following electrical stimulation to specific regions of the brain. When people laugh, subcortical, limbic regions of the brain and brain stem—most notably a region known as the pons, which is involved in sleep and breathing—are activated. These regions are much older evolutionarily than the cortical regions involved in language, suggesting that the deeper meaning of laughter is intertwined with breathing.
WHAT’S SO FUNNY ABOUT LAUGHTER
Laughter, then, is social and contagious. It empties the air deep in the cavities of our lungs, allowing heart rate and blood pressure to drop, the muscles of fight/flight exertion to go limp, and our psyche to fall into a calm state. These laughter facts fit nicely with the most enduring notion about the meaning of laughter, that it is the behavioral output of the experience of humor. Humor is as difficult to deconstruct as laughter, but there is consensus about the canonical structure of humorous acts: they involve some juxtaposition of contradictory propositions that produces a state of tension and ambiguity. The resolution of that contradiction then arrives in the form of a conceptual insight or punchline, the contradiction is resolved, and we laugh.
This hypothesis, that laughter serves to reduce tension, ran into some uncharitable data gathered by Robert Provine. Rather than restrict himself to the sterile confines of the laboratory, or rely on abstract, armchair conceptual analysis, Provine turned his astute ear to the laughter that occurs in the real world. He had three undergraduate assistants surreptitiously record bursts of laughter in malls, in friendly conversations on street corners, in the cafeteria banter of college students. This small band of laugh collectors recorded over 1,200 laughs in all. Provine transcribed these episodes into laughter narratives and then dissected what people were talking about just prior to laughter.
Humor often did precede laughter. Who wouldn’t have laughed or at least chuckled with head tilted back, closed eyes, and collapsed torso and shoulders after hearing the following statements?
; She’s working on a PhD in horizontal folk dancing.
You just farted!
Poor boy looks just like his father.
When they asked John, he said that he wanted to grow up to be a bird.
Do you date within your species?
Was that before or after I took off my clothes?
Is that considered clothing or shelter?
Humor-oriented utterances, however, represented only 10 to 20 percent of prelaugh statements. Importantly, Provine found that laughter followed all sorts of utterances. Over 80 percent of the laughs did not occur in response to humor. Consider some of the following utterances that produced laughter.
I see your point.
I hope we all do well.
We can handle this.
I told you so!
Are you sure?
Why are you telling me this?
What is that supposed to mean?!
Not exactly knee-slapping fare ready for The Daily Show, Saturday Night Live, Robin Williams, the class clown, or the town wit. If these elicitors of laughter were just exceptions to the rule, we could readily discount them. But conversational events unrelated to humor were the rule and not the exception, and beg for more precise theorizing about laughter.
THE COOPERATION SWITCH
What, then, is the conceptual unifier of the cackles, guffaws, hisses, chortles, snorts, and melodious songs that we hear every day, or at least on the days that are more pleasing to the soul? We have seen that the time-honored thesis—humor—does not suffice. It fails to explain many, even the vast majority, of laughs that occur in our daily living. For Bachorowski and her colleague Michael Owren, the answer is cooperation. In an insightful analysis, Bachorowski and Owren argue that laughter builds cooperative bonds vital to group living. It does so through two mechanisms.
The first is contagion: We routinely laugh, and experience exhilaration and levity, at the sound of another’s laugh. The contagious power of laughter motivated the introduction of laugh tracks on TV, a history that Provine details in Laughter. Recent neuroscience evidence suggests that when we hear others laugh, mirror neurons represent that expressive behavior and quickly activate action tendencies and experiences that simulate the original laugh in the listener’s brain. Specifically, laughter triggers activation in a region of the motor cortex in the listener, the supplementary motor area (SMA). Bundles of neurons leaving the SMA go to the insula and the amygdala, thus triggering the experience of mirth and amusement in the perceiver of the laugh. When we hear others laugh, this system of mirror neurons acts as if the listener is laughing.
Laughter builds cooperative bonds through a second mechanism, Bachorowski and Owren propose: Laughter rewards mutually beneficial exchanges—successful collaborations at work, in the kitchen, in child rearing, with friends. Laughter signals appreciation and shared understanding. Laughter evokes pleasure. Given that each individual has a signature laugh, produced by the particulars of the vocal apparatus, laughs become unique rewards of cooperative exchange, building trust between individuals.
This theorizing yields deep insights into laughter. Laughter is not simply a read-out of an internal state in the body or mind, be it the cessation of anxiety and distress or uplifting rises in mirth, levity, or exhilaration. Instead, laughter is also a rich social signal that has evolved within play interactions—tickling, roughhousing, banter—to evoke cooperative responses in others. The laughter as cooperation thesis brings together scattered findings in the empirical literature. A deadlocked negotiation between Palestinian and Israeli negotiators took a dramatic turn toward common ground and compromise after they had laughed together. In my own research with executives, laughter early in negotiations—the product of breaking-the-ice banter about families, travel mishaps, hotel rooms, golf games, and the like—sets the stage for mutually beneficial bargaining. Workplace studies find that coworkers often laugh when negotiating potential conflicts—in tight spaces, at tense team meetings, when critiquing a colleague’s work. Romantic partners who manage to laugh while discussing an issue of conflict find greater satisfaction in their intimate relations. Strangers who laugh while flirting in casual conversation report greater attraction. Friends whose laughs join in antiphonal form discover greater intimacy and closeness.
And what applies to the role of laughter in Middle East negotiations and the pyrotechnics of executives haggling, colleagues coexisting, and strangers flirting speaks to the long-term trajectories of attempts at connubial peace. John Gottman has found that for couples who were divorced on average 7.4 years after they were married, negative affect—for example, contempt and anger—was especially predictive of marital demise. For couples who divorced on average 13.9 years after they were married, it was the absence of laughter that predicted the end of their bond. In the early stages of a marriage, anger and contempt are highly toxic. In the later phases of intimate relations, it is the dearth of laughter that leads individuals to part ways. Without that cooperative frame for an intimate bond that laughter provides, as well as its attendant delights, partners move on.
Perhaps laughter is the great switch of cooperation. It is a framing device, shifting social interactions to collaborative exchanges based on trust, cooperation, and goodwill. Perhaps the pulse of a marriage is to be heard in the laughter the partners share. When I awaken and I hear my two daughters giggling in the antiphonal laughter that Bachorowski discovered, I know the morning will be fine, and relatively free of the conflicts of siblings as they seek their distinct niches in life. Perhaps our relationships are only as good as our histories of laughter together.
This theorizing, though, is in need of a bit more precision. We cooperate in many ways—through gifts, soothing touch, compliments, promises, and acts of generosity. Laughter must be associated with a more specific brand of cooperation.
Counterexamples to the laughter as cooperation hypothesis readily leap to mind. Bullies routinely laugh at their aggressive acts of humiliation (just listen to the shrill nerve jangling “ha, haa” of Nelson, the bully on The Simpsons). Some torturers at Abu Ghraib were heard to laugh at their victims. Thomas Hobbes wrote that laughter is the “sudden glory” produced by “the apprehension of some deformed thing in another” that makes people “suddenly applaud themselves”—a view that does not surprise given his portrayal of a dog-eat-dog world. Clues to a more precise conceptualization of laughter are found in its origins—in how play and laughter emerge in children, and what is being achieved, socially and conceptually, in the process.
THE ABUSE OF LANGUAGE
The acquisition of language in young children is breathtaking. Children learn ten or so words a day until the age of six, when the average child has a command of over 13,000 words. Children produce grammatically complex phrases even when not given such input from their parents, for example when parents speak pidgin. It is for these reasons that Steve Pinker called this high-wattage capacity the language instinct.
Just as remarkable, though, is how quickly children begin to abuse the rules of language. In particular, there is striking developmental regularity in the tendency for children, early in life, to violate basic rules of representation. They quickly start producing utterances that violate notions that words are supposed to refer to specific objects, and objects are to be characterized by specific words. And it is in this representational abuse that we find the core meaning of laughter—laughter indicates that alternatives to reality are possible, it is an invitation to enter into the world of pretense, it is a suspension of the demands of literal meaning and more formal social exchange. Laughter is a ticket to travel to the landscape of the human imagination.
In his analysis of the development of pretense, Alan Leslie details three kinds of pretend play in children. Each kind of pretend play hinges on the child violating the rules regarding correspondences between words and the objects to which they refer. In object substitution, the child substitutes nonliteral meanings of objects for the real meaning of the object. In the young chil
d’s world of pretend play, rocks become bread, swim goggles become cell phones, pillows become walls to fortresses, bedrooms become classrooms, older sisters petty rock stars or demanding old dames in the grocery store they run in the living room.
Children attribute nonliteral properties to objects in a second form of pretend play. While my daughters were five and three, respectively, I spent the better part of a year being a prince dancing with them at various balls. They insisted that I wear a certain pair of sweats, which they ascribed with the velvety beauty of a prince’s medieval tights. This form of play, founded on the attribution of pretend properties, shifted a bit later to a set of identities I felt much more at home in—the ogre or friendly gorilla—all pretend identities that derived from elaborations upon my physical status and regrettable postpartum paunch.
And finally, the young child’s world becomes filled with imaginary objects. In this third kind of pretend play, children simply imagine things that are not there—chalices in the princess’s cupped hand, swords, magic carpets, evil witches and comrades in common cause.
These forms of pretense emerge in systematic fashion at around eighteen months of age. They are all systematically accompanied by laughter. And they lead the child to develop the ability to use words to refer to multiple objects. As children free themselves from one-to-one relations between words and objects, they learn that words have multiple meanings. They also learn that objects can be many things—a banana can be a banana, a phone, an ogre’s nose, or a boy’s penis (when the parents aren’t around).
Born to Be Good_The Science of a Meaningful Life Page 14