This Is Your Brain on Music: The Science of a Human Obsession

by Daniel J. Levitin

The auditory cortex also has a tonotopic map, with low to high tones stretched out across the cortical surface. In this sense, the brain also contains a “map” of different pitches, and different areas of the brain respond to different pitches. Pitch is so important that the brain represents it directly; unlike almost any other musical attribute, we could place electrodes in the brain and be able to determine what pitches were being played to a person just by looking at the brain activity. And although music is based on pitch relations rather than absolute pitch values, it is, paradoxically, these absolute pitch values that the brain is paying attention to throughout its different stages of processing. This direct mapping of pitch is so important, it bears repeating. If I put electrodes in your visual cortex (the part of the brain at the back of the head, concerned with seeing), and I then showed you a red tomato, there is no group of neurons that will cause my electrodes to turn red. But if I put electrodes in your auditory cortex and play a pure tone in your ears at 440 Hz, there are neurons in your auditory cortex that will fire at precisely that frequency, causing the electrode to emit electrical activity at 440 Hz—for pitch, what goes into the ear comes out of the brain!