Born to Be Good: The Science of a Meaningful Life

Laughter produces a remarkable physical state. People laugh their heads and asses off. During laughter, the body goes limp. The individual is incapable of any sort of motion. I’ve asked my daughters in the midst of a bout of being tickled to try to willfully carry out certain basic movements—whistle, wink, stick their tongue out at me—and they didn’t come close. In the paroxysm of laughter, the body falls into a quiescent, otherworldly state.

And perhaps most subtly, laughter is intertwined with our breathing. In Boyle’s descriptions, laughter accompanies pushes of air out of the mouth. With the exception of certain pathological laughs (Merv Griffin, Arnold Horshack on the 1970s sitcom Welcome Back, Kotter), almost all laughter occurs as people exhale. This simple laughter fact may seem incidental to our understanding of laughter, but in fact it is fundamental. Here’s why.

Respiration and heart rate are two of the body’s most essential rhythms. These two rhythms play off each other like the voices of singers in an a cappella group. When you breathe in, your heart rate rises. When you breathe out, your heart rate drops, as does your blood pressure, and you move toward a state of relaxation.

This lung-heart dynamic has made its way into book titles (Waiting to Exhale), aphorisms (“Take a deep breath”), ethical mottoes in grammar-school classrooms (“Take a breath and count to ten”), the advice coaches give to their players attempting the game-winning free throw (they systematically exhale), and the thousand-year-old breathing exercises of yoga practices. Exhalation reduces fight/ flight physiology, especially heart rate, calming the body down. In fact, a series of studies in the 1970s and 1980s found that simply having individuals engage in deep breathing led to reduced blood pressure, stress, and anxiety, and increased calm.

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.