Harnessed: How Language and Music Mimicked Nature and Transformed Ape to Man

by Mark Changizi

  How about the second hurdle for a theory of music, the one labeled “emotion”? Could the mundane sounds of people moving underlie our love affair with music? As we discussed at the start of the chapter, music is evocative—it can sound joyous, aggressive, melancholy, amorous, tortured, strong, lethargic, and so on. I said then that the evocative nature of music suggests that it must be “made out of people.” Human movement is, obviously, made of and by people, but can human movement truly be evocative? Of course! The ability to infer emotional states from the bodily movements of others comes via several routes. First and foremost, when people carry out behaviors they move their bodies, movements that can give away what the person is doing; knowing what the person is doing can, in turn, be crucial for understanding the actor’s emotion or mood. Second, the actor’s emotional state is often cued by its side effects on behavior, such as when an exhausted person staggers. And third, some bodily movements serve as direct emotional signals, more akin to facial expressions and color signals: bodily movements can be proud, strutting, threatening, ebullient, jaunty, sulking, arrogant, inviting, and so on. Human movement can, then, certainly be evocative. And unlike evocative facial expressions and skin color signals, which are silent, our evocative bodily expressions and movements make noises. The sounds of human movement not only are “made from people,” then, but they can be truly evocative, fulfilling the “emotion” hurdle.

  An example will help to clarify how the sounds of human movement can be emotionally evocative. Michael Zampi, then an undergraduate at RPI, was interested in uncovering the auditory cues for happy, sad, and angry walkers. He first noted that University of Tübingen researchers Claire L. Roether, Lars Omlor, Andrea Christensen, and Martin A. Giese had observed that happy walkers tend to lean back and have large arm and leg swings, angry walkers lean forward and have large arm and leg swings, and sad walkers tend to lean forward and have attenuated arm and leg swings.

  “What,” Michael asked, “are the distinctive sounds for those three gaits?” He reasoned that leaning back leads to a larger gap between the sound of the heel and the sound of the toe. And, furthermore, larger arm and leg swings tend to lend greater emphasis to any sounds made by the limbs in between the footsteps (later I will refer to these sounds as “banging ganglies”). Given this, Michael could conclude that happy walkers have long heel-toe gaps and loud between-the-steps gait sounds; angry walkers have short heel-toe temporal gaps and loud between-the-steps gait sounds; and sad walkers have short heel-toe gaps and soft between-the-steps gait sounds. But are these cues sufficient to elicit the perception that a walker is happy, angry, or sad?

  Michael created simple rhythms, each with three drum strikes per beat: a toe-strike on the beat, a heel strike just before the beat, and a between-the-step hit on the off-beat. Starting from a baseline audio track—an intermediate heel-toe gap and a between-the-steps sound with intermediate emphasis—Michael created versions with shorter and longer heel-toe gaps, and versions with less emphasized and more emphasized between-the-steps sounds. Listeners were told they would hear the sounds of people walking in various emotional states, and then the listeners were presented with the baseline stimulus, followed by one of the four modulations around it. They were asked to volunteer an emotion term to describe the modulated gait. As can be seen in Figure 17, subjects had a tendency to perceive the simulated walker’s emotion accurately.

  Figure 17. Each column is for one of the three tracks having the sounds modulating around the baseline to indicate the labeled emotion. The numbers show how many subjects volunteered the emotions “angry,” “happy,” “sad,” or other emotions words for each of the three tracks. One can see that the most commonly perceived emotion in each column matches the gait’s emotion.

  This pilot study of Michael Zampi’s is just the barest beginning in our attempts to make sense of the emotional cues in the sounds of people moving. The hope is that by understanding these cues, we can better understand how music modulates emotion, and perhaps why genres differ in their emotional effects.

  If music has been culturally selected to sound like human movement, then it is easy to see why we’d have a brain for it, and easy to see why music can be so emotionally moving. But why should music be so motionally moving? The music-is-movement theory has to explain why the sounds of people moving should impel other people to move. That’s the third hurdle over which we must leap: the “dance” hurdle, which we take up next.

  Motionally Moving

  Group activities with toddlers are hopeless. Just as you get the top toddler into position at the peak of the toddler pyramid, several on the bottom level have begun crying, pooping, or wandering away. Toddlers prefer to treat their day-care mates as objects to ignore, climb over, or hit. And just try getting a dozen of them to do anything in unison, like performing “the wave” in the audience at a roller derby! If aliens observed us humans only during toddlerhood, they might conclude that we don’t get on well in groups, and that, lacking a collaborative spirit, we will be easy prey when they invade.

  But brain-thirsty aliens might come to a very different conclusion if they dropped in on a day-care center during music time. Flip on “The Wheels on the Bus Go Round and Round,” and a dozen randomly wandering, cantankerous droolers begin shaking their stinky bottoms in unison. Aliens might surmise that music is some kind of marching order, a message from the human commander to activate gyrations against an invading enemy.

  Dancing toddlers, of course, play little or no role in explaining why we haven’t been invaded by aliens, but they do raise an important question. Why do toddlers seem to be compelled to move to the music? And, more generally, why is this a tendency we keep into adulthood? At this very moment of writing, I am, in fact, swaying slightly to Tchaikovsky’s Piano Concerto No. 1. Don’t I have better things to do? Yes, I do—like write this book. Yet I keep pausing to hear the music, and end up ever so slightly dancing. It is easy to understand why people dance when a gun is fired at their feet like in old Westerns, but music is so much less substantial than lead, and yet it can get us going as surely as a Colt 45. What is the source of music’s power to literally move us, like rats to the Pied Piper’s flute?

  We can make sense of this mystery in light of the theory that music sounds like human movement. If music sounds like movement, and music makes us move, then it is not so much music that is making us move, but the sound of human movement. And that’s not at all mysterious! Of course the behaviors of others may elicit responsive actions from us. For example, if my three-year-old son barrels headlong toward my groin, I quickly move my hands downward for protection. If he throws a rubber ball at my head, I try to catch it. And if he suddenly decides he’d rather not wear his bathing shorts, I quickly pull them back up. Not only do I behave in reaction to my son’s behavior, but my behavior must be timed appropriately, lest he careen into me, bean me with a ball, or strip buck-naked and get a head start in his dash away. Music sounds like human behavior, and human behavior often elicits appropriately timed behavioral responses in others, so it is not a surprise, in light of the theory, that music elicits appropriately timed behavioral responses.

  It’s easy to see why three-year-old aggressive and streaking behaviors would prompt a well-timed response in others (especially parents). Another common category of human behavior that elicits a behavioral response in others, in fact one of the most common, is expressive behavior. Human expressions are for other humans to see or hear or smell, precisely in order to prompt them to modulate their behavior. Sometimes another person’s response may be a complex whole-body behavior (I give my wife my come-hither look, she responds by going thither), and sometimes the other person’s behavioral response may simply be an expression of emotion (I grimace and rub my newly minted bruise, and my son responds by smiling). If music is good at getting us to move, then, in this light, one suspects that music must usually sound not merely like movement that kicks (literally, in my son’s case) listeners into moving in response, but,
more specifically, like human emotional or expressive behaviors.

  Sound triggering movement. That’s starting to sound a bit like dance. To more fully understand dance, we must grasp one further thing: contagious behaviors—behavioral expressions that tend to spread. For example, if I smile, you may smile back; and if I scowl, you’ll likely scowl back. Even yawns are catching. And contagious behavior is not confined to the face. Nervous behavior can spread, and angry bodily stances are likely to be reciprocated. If you raise your hands high into the air, a typical toddler will also do so, at which point you have a clear tickle shot. Even complex whole-body behaviors are contagious, accounting for why, for example, people in a crowd often remain passive bystanders when someone is being attacked (other people’s inaction spreads), and how a group of people can become a riotous mob (other people’s violent behavior spreads). By the way, have you yawned yet?

  Music, then, may elicit movement for the same reasons that a cartoon smiley face can elicit smiles in us: music can often sound like contagious expressive human behavior and movement, and trigger a similar expressive movement in us. Music may not be marching orders from our commander, but it can sometimes cue our emotional system so precisely that we feel almost compelled to march in lockstep with music’s fictional mover. And this is true whether we are adults or toddlers. When music is effective at getting us to mimic the movement it mimics, we call it dance music, be it a Strauss waltz or a Grateful Dead flail.

  The music-sounds-like-movement theory can, then, explain why music provokes us to dance—the third of the four hurdles a theory of music must leap over. The fourth and final hurdle concerns the structure of music, and it will take the upcoming chapter and the Encore chapter to make the case that music has the signature structure of humans moving.

  Don’t Roll Over, Beethoven

  The case for my theory is strong, I believe, and I hope to convince you that music sounds like human movement. If I am correct, then, with the movement-meaning of music in hand, we will be in a position to create a new generation of “supermusic”: music deliberately designed to be even more aesthetically pleasing, by far, than previous generations of music. Music has historically been “trying” to shape itself like expressive human behaviors, in the sense that that was what was culturally selected for. But individual composers didn’t know what music was trying to be—composers didn’t know that music works best when tapping into our human-movement auditory mechanisms. Musical works have heretofore tended to be sloppy mimickers of human movement. With music decoded, however, we can tune it perfectly for our mental software, and blow our minds. You’re toast, Beethoven! I’ve unraveled your secrets!

  No. Just kidding. I’m afraid that the music research I’m describing to you will do no such thing, even if every last claim I make is true. To see why the magic of Beethoven is not unraveled by my theory, consider photographic art. Some photographs have evocative power; they count as art. Some photographs, however, are just photographs, and not art. What exactly distinguishes the art from the “not” is a genuine mystery, and certainly beyond me. But there is something that is obviously true about art photographs: they are photographs. Although that’s obvious to us, imagine for a moment that four-dimensional aliens stumble upon a pile of human artifacts, and that in the pile are photographs. Being four-dimensional creatures, they have poor intuitions about what a three-dimensional world looks like from a particular viewpoint inside it. Consequently, our human photographs are difficult to distinguish from the many other human artifacts that are flat with stuff printed upon them, such as wallpaper, clothing, and money. If they are to realize that the photographs are, in fact, photographs—two-dimensional representations of our 3-D world—they are going to have to discover this.

  Luckily for them, one alien scientist who has been snooping around these artifacts has an idea. “What if,” he hypothesizes, “some of the flat pieces of paper with visual marks are photographs? Not of our 4-D world, but of their human 3-D world?” In an effort to test this idea, he works out what the signature properties of photographs of 3-D worlds would be, such as horizons, vanishing points, projective geometry, field of focus, partial occlusion, and so on. Then he searches among the human artifacts for pieces of paper or fabric having these properties. He can now easily conclude that wallpaper, clothing, and money are not photographs. And when he finds some of our human photographs, he’ll be able to establish that they are photographs, and convince his colleagues. This alien’s research would amount to a big step forward for those aliens interested in understanding our world and how we perceive it. A certain class of flat artifacts is meaningful in a way they had not realized, and now they can begin to look at our photographs in this new light, and see our 3-D world represented in them.

  The theory of music I am defending here is akin to the alien’s theory that some of those flat artifacts are views of 3-D scenes. To us, photographs are obviously of 3-D scenes; but to the aliens this is not at all obvious. And, similarly, to our auditory system, music quite obviously is about human action; but to our conscious selves this is not in the least obvious (our conscious selves are aliens to music’s deeper meaning).

  To see why this book cannot answer what is good music, consider what this alien scientist’s discovery about photographs would not have revealed. Unbeknownst to the alien, some of the photographs are considered by us humans to be genuine instances of art, and the rest of the photographs are simply photographs. This alien’s technique for distinguishing photographs from nonphotographs is no use at all for distinguishing the artful photographs from the mere photographs. Humanity’s greatest pieces of photographic art and the most haphazard kitsch would all be in the same bag, labeled “views of a 3-D world.” By analogy, the most expressive human movement sounds and the most run-of-the-mill human movement sounds are all treated the same by the ideas I describe in this book; they are all in the same bag, labeled “human movement sounds.” Although it is expressive human movements that probably drive the structure of music, I have enough on my hands just trying to make the beginnings of a case that music sounds like human movement. Just as it is easier for the four-dimensional alien to provide evidence for photograph-ness than to provide evidence for artsy-photograph-ness, it is much easier for me to provide evidence that music is human-movement-ish than to provide evidence that it is expressive-human-movement-ish. Photographic art is views of 3-D scenes, but views of 3-D scenes need not be photographic art. Similarly, music is made of the sounds of humans moving, but the sounds of humans moving need not be—and usually are not—music.

  Relax, Beethoven—no need to roll over. If the music-sounds-like-movement theory is correct, then it is best viewed as a cipher key for decoding music. It gives our conscious, scientific selves the ability to translate the sounds of music back into the movements of humans (something our own lower-level auditory areas already know how to do). But knowing how to read the underlying movement meaning of music does not mean one knows how to write music. Just as I can read great literature but cannot create it, a successful music-is-movement theory will allow us to read the meaning of music but not to compose it. Creating good music requires knowing which human movements are most expressive, and making music sound like that. But a theory of expressive human movements is far harder to formulate than a theory of human movements generally. All I can hope to muster is a general theory of the sounds of human movements, and so the theory will be, at best, a decoder ring, not a magical composer of great music.

  But a decoder ring may nevertheless be a big step forward for composers. Composers have thus far managed to create great music—great auditory stories of human movements, in our theory’s eyes—without explicitly understanding what music means. With a better understanding of the decoder ring, composers can consciously employ it in the creative process. Similarly, the four-dimensional alien has much better odds of mimicking artistic photography once he has figured out what photographs actually look like. Until then, the alien’s attempts at artis
tic photography wouldn’t even look like photography. (“Is this photographic art?” the alien asks, holding up a plaid pattern.) The aliens must know what basic visual elements characterize photography before they can take it to the next level, start to guess which arrangements of those elements are superior, and try their own tentacles at art photography. You can’t have expressive photography without photography, and you can’t have expressive human movement sounds without human movement sounds. The theory of music I’m arguing for, then, does not explain what makes great music. But the theory would nevertheless be a big step forward for this. Like the alien’s basic discovery, it will enable us to pose hypotheses about why some music is great—by referring to the expressive movements and behaviors it depicts.

  This decoder ring will, then, be helpful to composers, but it cannot substitute for the expressive antennae composers use to create musical art. For choreographers and movie composers, this decoder ring is potentially much more important. Choreographers and movie composers are deeply concerned with the mapping of music to movement (the principal domain of choreography) or from movement to music (the principal domain of movie composers), and so a decoder ring that translates one to the other is a potential holy grail. In reality, though, it’s not as simple as that. A given piece of music probably does not determine particular dance moves (although your auditory system may pick out just one movement)—a good choreographer needs an artistic head to pick the most appropriately expressive movement of the many possible movements consistent with the music. And for any given movie visual, a good film composer will have to use his or her artistic talents to find an appropriately expressive theme for the scene. Any music–movement decoding devices made possible by this book won’t put choreographers or movie composers out of work, but such a decoder may serve as an especially useful tool for these disciplines, providing new, biologically justified constraints on what makes a good music-movement match.