For most of us, on those rare occasions when we listen to classical music, we prefer composers who wrote before the 20th century. At the symphony we find the music of Ludwig van Beethoven and Franz Schubert much more pleasing and comprehensible than the jarring dissonances of Luciano Berio and Arnold Schönberg. The New Yorker music critic Alex Ross, in his history of modern classical music, wrote that this music "sounds like noise to many." Although a century has passed since the composition of many pioneering works of 20th century music, it "still sends ripples of unease through concert audiences."
The composers of this modern music often believed that, compared to the consonant harmonies of Mozart and Bach, their works were a more convincing representation our inner psychological states. But the results of a recent study indicate that traditional harmonies are more naturally perceived by our brains. A team of researchers at the Free University of Berlin found that we perceive music in much the same way that we perceive language—and that traditional musical harmonies usually sound better to us because they play to our brain's innate ability to perceive patterns in music.
Perhaps humans find music so universally compelling because it speaks to our natural cognitive strengths.
A key feature of how we process language is our ability to capture "non-local dependencies," which is a technical way of saying that we naturally assemble larger units of meaning by composing phrases and sentences from smaller building blocks. We effortlessly parse the meaning of the sentence: "Stealing the eggs from an enraged, 10-foot crocodile is a delicate operation." We grasp the main point that "stealing the eggs ... is a delicate operation," even though nested within that main point is a phrase elaborating that the eggs are taken from a large, angry reptile.
These kinds of hierarchical grammatical structures come naturally to us when we speak. Do our brains work the same way when we listen to music?
STEFAN KOELSCH AND HIS colleagues in Berlin set out to test the idea that we naturally perceive complex structures in music, much like we perceive the same kinds of structure in language. The researchers began with the observation that composers deliberately put meaningful, large-scale patterns into their music. As in language, larger meaning in music is made up of small units. A piece is written in a particular key, and the moment-by-moment harmonies of the piece reinforce that key. Composers of almost any kind of music invest substantial effort into creating larger patterns from small units of harmony. But do our brains perceive those larger patterns as we listen, without doing a conscious, in-depth analysis?
To test this idea, the scientists had volunteers listen to excerpts from classical choral music by Johann Sebastian Bach. The volunteers listened to both the original version and a subtly modified version. In the original version, the music began and ended on the same chord; what happened in between was Bach's elaboration of a coherent musical idea. But in the modified version, the researchers shifted the opening harmony slightly, while leaving the ending unchanged. The result was a piece that, superficially, sounded the same as the original, but it had lost its larger-scale musical coherence.
The volunteers (which included musicians and non-musicians) listened to these musical excerpts in random order, and the researchers recorded their response to the music in two ways: by measuring the electrical activity of the volunteers' brains and by having the volunteers complete a questionnaire. Remarkably, the electrical measurements showed that the brains of both the musicians and non-musicians reliably perceived the differences between the two musical samples. In the questionnaires, some of the musicians were able to pinpoint exactly what had been changed, while most of the other volunteers noted that the modified excerpt felt less conclusive.
The scientists argued that their results show that "both music and language make use of more general resources for the processing of hierarchically organized information than previously believed." Perhaps humans find music so universally compelling because it speaks to our natural cognitive strengths. And perhaps because the works of many 20th century classical composers violate our intuitive expectations, we have a difficult time drawing emotional meaning from this music without being steeped in the theory behind it. These composers believed that traditional Western harmonies were as much an arbitrary cultural construct as the alternative harmonic systems they were developing. But it's likely that J.S. Bach, and millennia of musicians around the world before him, were tuned in to the core ability of our minds to perceive larger harmonic patterns—and without those patterns, we're likely to just hear noise.