There was a time when soldiers went into battle in columns and rows. They would line up and march in orderly formation toward the enemy, armed with spears, bayonets or some other weapon of close combat. The enemy would do the same thing. One of these well-oiled formations would kill more soldiers than the other—and win the battle.
Advances in firearms long ago made the marching formation obsolete. It just does not work with machine guns and guerilla warfare. Yet armies all over the world still train for this archaic kind of warfare. Indeed, militaries continue to place a high value on precision and synchrony that will never be used on a battlefield.
Why is that? Why do high schools have marching bands? Why do churches have choirs? And perhaps most perplexing of all, why do we have synchronized swimming? What is it about moving and chanting and singing in unison that appears to have universal appeal?
Bonding and Effervescence
Anthropologists and cultural historians have offered up a variety of theories about synchrony over the years, mostly having to do with group coherence. One theory, for example, holds that various communities benefit from the actual physical synchrony—or “muscular bonding”—which builds group cohesiveness. Another idea is that synchronous activities lead to “collective effervescence”—positive emotions that break down the boundaries between self and group.
But neither of these theories has been proved, and what is more, neither is complete. Muscular bonding may explain the coherence of the 14th Infantry Regiment, but those guys do not seem very effervescent—not in the way that, say, carnival revelers are. And gross motor coordination does not explain the almost motionless chanting of Tibetan monks. Psychologists are looking for a unifying theory for the appeal of synchrony.
One idea, put forth by Stanford University psychologist Chip Heath and graduate student Scott S. Wiltermuth, is that all synchrony—movement and sound, and both together—is an ancient ritual that evolved for the economic benefit of the group. The primary goal of rhythmic dancing, marching and chanting is to solve the problem of the freeloader—the community member who hurts the collective good by taking but not contributing. Muscular bonding and collective joy are mere by-products of this more fundamental economic ritual.
Heath and Wiltermuth ran a series of experiments to test this idea. In the simplest version, the researchers took groups of Stanford students on walks around campus; some walked in step—marching, basically—whereas others just strolled the way people usually do. Later, after the subjects thought the experiment was over, the psychologists gave them all the Weak Link test, in which each volunteer chooses to act either self-interestedly or cooperatively, depending on what he or she anticipates others will do. The test measures the expectation that others will value the group over themselves.
The marchers acted more cooperatively than the strollers did. They also said that they felt more “connected” than the strollers did. Notably, they did not report feeling any happier, suggesting that positive emotions were not necessary for achieving the boost in group cohesiveness.
The psychologists wanted to do a more fine-grained test of their idea. It is well known that a sense of common identity and shared fate strengthens group cohesiveness, but the researchers wanted to see if synchrony contributes above and beyond this feeling. They did a rather elaborate test to find out. They had students perform tasks—moving plastic cups—that required differing degrees of coordination with others. While doing this, the subjects listened to “O Canada” through headphones. Remember that these participants were from Stanford (and thus typically U.S. citizens), so the Canadian national anthem presumably had no emotional resonance for them; it was merely a synchronous act.