"This Is Your Brain on Music"

Neuroscientist Daniel Levitin's wonderful new book explains why music is a critical step in human evolution and why the songs we loved as teens remain stuck on "play" in our heads.

By Farhad Manjoo

Read more: Books, Music, Psychology, Reviews, Book reviews, Farhad Manjoo

Sept. 5, 2006 | If you happened to have been born between about 1978 and 1981, there's a fair chance you count yourself an obsessive of the Southern California rock band Weezer. The affection would not make sense to those even just a bit older or younger, who might regard Weezer's guitar pop as clever and pleasing but also somewhat too shallow to have much lasting significance. Those of a certain age, though, experienced the group's 1994 eponymous debut release, known to fans as the Blue Album, as a thing of precise and overflowing emotion -- 10 tracks that functioned like keys to secret locks in the teenage brain, opening up all the awkwardness and anxiousness of those melodramatic high school years.

We all have music like this, music that burns into the soul when we're young and remains essential for the rest of time. For me it was the Blue Album and anything the Smashing Pumpkins did up until about 1998. For you it's something else, but it's surely something -- there's a tape or record or CD that once knocked you out with a force that, cheesy as it is to remember, felt like true love. Put on one of those songs now and, if it's been a long time, the effect is like an old movie; the scenes play back for you in entire exhilarating reels. What's happening when music captures you in this way deserves some scrutiny. You may feel like the songs are grabbing your heart, but what's actually going on is in your head. There, says Daniel J. Levitin in his new book "This Is Your Brain on Music," an "exquisite orchestration of brain regions" are engaged in a "precision choreography of neurochemical uptake and release." Why human beings make and enjoy music is, in Levitin's telling, a delicious story of evolution, anatomy, perception and computation -- a story that's all the more thrilling when you consider its result, the joy of living in a world filled with music.

Levitin is a neuroscientist and a former record producer. He is one of those people -- think of a Nick Hornby character -- for whom music has always been a source of infinite aesthetic and emotional pleasure. He is also one of those people lucky enough to have turned his abiding interest into worthwhile work. Levitin's primary scientific pursuit concerns how music operates on the human brain, though it might be more fitting to say that he uses music to study how everything works in the human brain. By looking at how our brains process music -- at how we turn collections of sounds into patterns that we think of as songs, how we remember and categorize those patterns, and how we feel them as intense emotion -- Levitin and other scientists have uncovered important neural processes that had previously eluded researchers. The brain systems they discovered explain why music -- whether in high school or in life beyond -- can touch you so deeply: Our brains seem to have evolved to maximize musical ability. Indeed, Levitin argues, music has been essential to our very success as a species.

Levitin's book has an unfortunate PSA- related title, but otherwise "This Is Your Brain on Music" is delightful. Levitin explains the intricacies of two difficult subjects -- neuroscience and music theory -- without ever losing the reader; it helps that he's got what Stevie Wonder refers to in a blurb as "an encyclopedic knowledge of popular music," which allows him to reference a wide range of traditions, from classical to the blues to jazz, rock, country and modern pop, in order to convey certain complex ideas.

Levitin also has a knack for the choice analogy. Here is how, for example, he describes why it's remarkable that our brains can extract audio information from the chaotic collection of air molecules bouncing against our eardrums: "Imagine that you stretch a pillowcase tightly across the opening of a bucket, and different people throw ping-pong balls at it from different distances," Levitin writes. "Each person can throw as many ping-pong balls as he likes, and as often as he likes. Your job is to figure out -- just by looking at how the pillowcase moves up and down -- how many people there are, who they are, and whether they are walking toward you, walking away from you, or are standing still. This is analogous to what the auditory system has to contend with in making identifications of auditory objects in the world, using only the movement of the eardrum as a guide."

Levitin's point is that when we're listening to music, our brains are engaged in an enormously complex computational task -- so complex that no man-made computers have yet been able to do anything nearly as sophisticated with sound. Another insight is that much of what we think of as the sounds of the world actually occur inside our heads, not outside. The air molecules that strike our eardrums, for instance, carry no inherent "pitch." Instead, the molecules oscillate at a specific rate, and our brains measure the rate, and then construct an internal representation -- a high or low pitch -- based on that frequency. (In the same way, light waves carry no color -- our eyes and brains construct color by measuring the frequency of the waves.) In other words, sound is essentially a psychological phenomenon. If a tree falls in the forest and no one is there to hear it, does it make a sound? "Simply no," Levitin points out. "A suitable measuring device can register the frequency made by the tree falling, but truly it is not pitch unless and until it is heard."

Your brain doesn't just come up with an internal representation of sound, it also derives meaning -- in particular, pleasure -- from sound. But how it does so surprises even neuroscientists. In his lab, Levitin has found that when people listen to a song they like -- as opposed to something that they don't like, or simply noise -- one area of the brain that's activated is the cerebellum. This seemed odd: The cerebellum is, evolutionarily, one of the oldest parts of the brain, what some people call the reptilian brain; its main purpose is to coordinate the movement and timing of our bodies, and not, scientists believed, anything more sophisticated, such as the experience of emotions. But if the cerebellum wasn't involved in emotion, why was it being activated only when people listened to something that they liked -- an emotional choice -- rather than just anything at all?

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