In 2004, Ian McDonald, M.D., a British neurologist and amateur classical pianist, experienced a stroke that damaged a fairly small area of his brain. As a result, he temporarily lost his ability to read and play music from a score, as well as to appreciate music emotionally. What does his experience, and that of other people whose musical abilities have been affected by brain damage, teach us about how the brain binds together what we perceive into a seamless flow?
As we interact with our environment in the course of our daily lives, most of us take for granted the smoothness with which the flow of events blends together. Our brains stitch together what might otherwise seem to be a disjointed sequence of individual events into a coherent stream of information about the world around us. Language is an obvious example, of course, as letters are bound together into words, words are grouped into phrases and sentences, and sentences form paragraphs and discourse. But music, too, relies on our ability to bind together smaller elements into Musical behaviors include the same elements of perception, action, emotion, and other mental operations as so many other kinds of behavior. larger structures. Individual notes are strung together to form melodic motifs. Melodic motifs are used to shape phrases, which in turn form songs or even movements of symphonies. Notes sung simultaneously by different voices or played by different instruments are combined to create harmonies. How our brains bind together these discrete pieces of auditory information to create the experiences of hearing, remembering, or performing music is at the heart of a recent surge of neuroscience research aimed at understanding this ubiquitous human phenomenon.
Despite music’s central role in human cultures around the world, and its potential to help unlock the mechanistic secrets of the brain, its arrival on the scientific scene is rather recent. Nonetheless, exploring music’s basis in the brain can help shed light on a remarkable human activity that has been a part of our social and cultural fabric for millennia. Moreover, while the relegation of music to scientific second fiddle is understandable, we should not minimize the role that music can play in our broader understanding of how the brain works.
Translating a Musical Score into Action
Understanding how the brain accomplishes music is likely to enhance our understanding of the brain’s inner workings for the simple reason that musical behaviors include the same elements of perception, action, emotion, and other mental operations as so many other kinds of behavior. To get a handle on how music might be processed by the brain, scientists use two primary methods: case studies of people who have suffered some form of brain damage and neuroimaging studies to measure physiological changes in the brains of healthy people while they perform various tasks related to music, such as remembering short melodies or reproducing rhythms. Studying people with an injury to the brain provides a particularly fascinating window into the workings of the brain because it helps researchers understand general principles of brain organization while taking into account variations in individual cases.
Following damage to the brain, such as the death of tissue after a stroke, a person is likely to experience deficits—whether in perception, movement, attention, or memory—that make performing previously routine behaviors and tasks more difficult. If neurologists carefully identify these deficits, they can pinpoint the specific mental operations that are impaired. When multiple patients who have damage to the same brain area experience the same deficits, the neurologist can ascribe the underlying mental operations to specific brain areas. For example, damage to the left side of the frontal lobe of the brain in a region known as Broca’s area results in Broca’s aphasia, the inability to produce sequences of speech sounds and words.
Closer scrutiny of individual patients presents a more intriguing picture, however. Often some highly specific functions are lost but others are spared, despite the brain damage being widespread or occurring in a region commonly associated with a multitude of functions. My launching point for exploring music in the brain in this article is the remarkable personal account of one such patient, Ian McDonald, M.D.1
McDonald was a British neurologist with an avocation as a classical pianist. He was a skilled musician who spent much time playing the piano, both alone and in small chamber music groups. But as a result of a stroke in 2004, he lost his ability to read and play music from a score, as well as to appreciate it on an emotional level. Fortunately, he documented both his symptoms and his recovery. His report, taken together with other similar case studies, provides insight into the role that the brain’s parietal lobes play in transforming information from one form into another and in binding together the stream of events into a continuum of meaningful experience.