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In Focus
January 22, 2001
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Exploring the Musical Brain
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Music may be even more ancient
than the human race, over which it holds tremendous sway. Scientists
are beginning to find out why
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By
Kristin Leutwyler
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 NEANDERTAL FIREPLACE
in France may have offered warmth to our ancestors as they joined to
play and listen to the animal-bone flutes recently found in the area.
The remarkable musical instruments are as much as 53,000 years old—more
than twice as old as the famed cave paintings in Lascaux. |
It can bring us to tears or to our feet, drive us into battle or lull
us to sleep. Music is indeed remarkable in its power over all
humankind. Perhaps for that very reason, no human culture on earth has
ever lived without it: people making music predates agriculture and
perhaps even language. Take, for instance, the recent discoveries in
France and Slovenia of surprisingly sophisticated, sweet-sounding
flutes, made by our Neandertal cousins. Some of these instruments,
carved from animal bones, are as much as 53,000 years old—more than
twice as old as the famed cave paintings in Lascaux.
Despite the ancient and primal nature of music, though, scientists have
struggled with some very fundamental questions about its origins and
purpose. How does the brain process music? Are there special neural
circuits dedicated to creating or interpreting it? If so, are they,
like language, unique to human beings? Or do other animals possess true
musical ability? Why is an appreciation for music practically
universal? Has it conveyed some evolutionary advantage through time?
The field of biomusicology is still fairly young, but during the past
few years, it has started to answer some of these questions. |
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most basic, researchers have discovered that music—like
language—stimulates many areas in the brain, including regions normally
involved in other kinds of thinking. For this reason, Mark Jude Tramo
of the Harvard Medical School argues in a recent issue of Science
that the brain doesn't have a specific "music center," as others have
suggested. As an example, he points to the left planum temporale. This
tiny brain region is critical to the golden musical gift of perfect
pitch—the rare ability to recognize by ear a perfect middle C hit on
the piano, or the E of a passing car horn. But the left planum
temporale also plays an important role in language processing. Thus,
Tramo writes, there is "no grossly identifiable brain structure that
works solely during music cognition. However, distinctive patterns of
neural activity within the auditory cortex and other areas of the brain
may imbue specificity to the processing of music."
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revealed themselves through neuroimaging studies—others through tests
on patients that, like the subjects of Oliver Sacks's popular books,
have suffered unusual forms of brain damage. In the late 1990s, for
instance, Isabelle Peretz at the University of Montreal and Catherine
Liégeois-Chauvel of INSERM in Marseilles ran several experiments on 65
people who, because of epilepsy, had had part of one or the other
temporal lobe surgically removed. From these studies they concluded
that musicality resided primarily on one side of the brain—the right
hemisphere.
The experiments were simple: Peretz and Liégeois-Chauvel played
different songs for each patient twice. Sometimes the melodies were
exactly the same. Other times, they had changed in one of several
attributes, which researchers describe as "dimensions": first among
them is pitch, which pertains to the actual frequency of a particular
tone; the second is rhythm, or the duration of series of notes; the
third is tempo, the overall pace of a piece; the fourth is contour,
which describes the shape of a melody, or its pattern of rises and
falls in notes; the fifth is key, or the set of pitches to which notes
in a melody belong; other dimensions include timbre, loudness and
spatial location. |
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