The Etiquette of the Explosion

The sneeze is often filed among biology's few non-negotiable outbursts, a violent clearing of the nasal passages that arrives with the inevitability of a breaking wave. Yet while the physiological mechanics are universal, the sound we make while sneezing is a surprisingly local affair. In English-speaking corridors, the event is almost always punctuated by a sharp "achoo." In Tokyo it is a "hakashun"; in Paris, an "atchoum"; in Berlin, a "hatschi." These are not competing phonetic attempts to describe the same noise, but socialized sound effects we begin to mimic long before we are conscious of the habit.

The clearest evidence for this conditioning comes from people who have never heard a sneeze. Individuals born profoundly deaf do not "achoo." Their sneezes consist of the raw, unadorned sound of air moving fast through the throat and nose—a heavy sigh or a sharp huff of wind—without the vocal flourishes that hearing people feel compelled to add. The "achoo," in other words, is not a reflex but a performance, a voluntary nonverbal vocalization learned through a lifetime of auditory feedback. We hear how our parents and neighbors sneeze, and our brains, ever eager to conform, fire a split-second signal to the vocal cords to make the explosion sound "normal."

This traffic between biology and artifice extends beyond the nose. Research into other primal sounds—the roars of aggression, the cries of pain—finds that these too draw on a library of heard experiences to reach their stereotypical forms. People who cannot hear themselves or others produce versions that are acoustically atypical, and listeners tend to rate them as less authentic. Even in our most desperate moments of irritation or agony, we are still, in some small way, checking the room to see how the part should be played. We are rarely as involuntary as we think, even when we are blowing our own minds.