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12/15/2004
Tuning the Brain
This was a memorable musical week, beginning with the sixth
grade holiday concert at our grandson’s school. The all-string
orchestra performed valiantly. However, lacking instruments of
the Stradivarius quality and the more expensive bows that bring
life to the instruments, the depth of these young musicians’
accomplishments could not be fully expressed. The sixth grade
band, with its percussion section masking some instrumental
weaknesses, sounded quite good. The chorus was the highlight.
The boys’ voices have not yet begun to change and there’s a
certain angelic quality to them that’s appropriate to the Christmas
season. The numbers were lively, featuring a good bit of spirited
arm and body movement, and were quite enjoyable, capped by
the appearance of Santa.
During my career at Bell Labs, many of the scientific meetings
that I attended were in Boston. I always regretted that we never
got to a performance of the Boston Pops. That was remedied this
week when we joined a group at the New Jersey Performing Arts
Center in Newark for a very enjoyable concert of Christmas and
Chanukah music by the Pops under the direction of Keith
Lockhart. The orchestra was enhanced by the Boston Pops
Holiday Chorus and a 17-year-old vocalist, Hayley Westenra
from New Zealand. She was an attractive young lady with a
beautiful voice. Lockhart was wearing a red shirt and red socks,
pointedly reminding the audience that, in Boston, red socks are
quite popular. This remark drew good-natured boos from some
in the audience, obviously Yankee fans. As with the sixth grade
concert, the climax came with an appearance by Santa.
Music certainly plays an important role in virtually all cultures.
Today, we have electronic devices that store hundreds of songs
and the media are filled with stories of illegal downloading of
music and the search for ways to assure proper compensation for
the recording artists. Music has been around in human groupings
for at least some 50,000 years as evidenced by findings of
primitive bone flutes dating that far back. Suggestions have been
made that music arose in humans as a means to impress potential
mates or as a means to keep communities together. I like to
think that it was simply a case of some Neandertal guy or gal
listening to a mockingbird sing and figuring out that putting
holes in a bone and blowing accomplished the same thing.
Patricia Gray, head of the Biomusic program at the National
Academy of Sciences, points out that humpback whales have
been making music for millions of years and that they sing songs
very much along the same patterns as do humans. A song may
last about 20 minutes, with repetition of certain refrains, and they
may repeat the same song over and over again for hours.
According to Gray and colleagues, the whales even use refrains
that rhyme and the researchers speculate that the humpbacks use
rhymes to help them remember, just as we do. Whales seem to
appreciate good music. There was a study of some humpbacks
that wandered from the Indian Ocean to the Pacific Ocean, where
they met some native whales. Some of the latter decided they
liked the Indian’s song so much they switched and, within 3
years, were singing just the Indian Ocean tune.
With modern techniques for imaging the brain, researchers have
been trying to figure out how and where music is processed and
stored in the brain. At first it was though there might be one
“music center” in the brain but that notion has proved not to be
the case. Instead, music causes action in various parts of the
brain, some of which are used in other forms of perception. An
article, “Music and the Brain”, in the November issue of
Scientific American describes this work. The author is Norman
Weinberger, is the founder of the Center for the Neurobiology of
Learning and Memory at the University of California, Irvine.
Let’s follow a few bars of music out of my grandson’s
saxophone into my brain. These few bars are not simple. Each
note has a certain “pitch”, or frequency. Then there is “rhythm”,
the duration of a bunch of notes, not to mention “tempo”, which
is the overall pace. There’s also “contour”, the shape of a
melody that encompasses the rise and fall of the notes. There’s
the “key”, which is the set of pitches to which the notes belong.
There’s the “tone”, the effect of the pitch and loudness of the
note and there’s “timbre”, the characteristic that distinguishes
between the same note played by a violin or a saxophone.
Well, those notes, as sound waves, go scooting through the ear to
the inner ear and the cochlea, which contains something called
the basilar membrane. This membrane, struck by the sound
waves, vibrates and causes tiny hair cells to send electrical
signals through auditory nerve fibers. The 3,500 or so hair cells
are each tuned to different frequencies. The auditory nerve fibers
deliver their signals to individual neurons, and the trains of
electrical signals end up in the auditory cortex in the brain. In the
auditory cortex the different cells (neurons) respond best to
certain frequencies but there is some overlap of frequencies in
neighboring cells so there isn’t any gap in frequency response.
It was thought for some time that when a cell detected a certain
frequency it would respond the same way every time. Not true.
Weinbereger and a colleague at UC Irvine, Thomas McKenna,
studied individual neurons in cats (don’t want to do this in
humans!). They found that the response, number of firings, of
the neurons changed when the note was for example, the first
note as opposed to being in among a series of notes. They also
found that the response depended on the contour, that is, was it
part of a rising or falling contour.
A remarkable feature of the auditory cortex is that it can be
“retuned”. If the brain finds that certain tones are “important”,
the cells can shift their response to a new frequency. This
devotes more cells to that frequency and leads to a greater overall
response to that frequency. Weinberger and colleagues showed
this retuning by working with guinea pigs. First they looked at a
bunch of cells and found which tones produced the greatest
responses. Then they took a tone that was not one of these
preferred tones and used that tone to precede a mild shock to the
foot of the guinea pigs. Very quickly the guineas learned that
tone was trouble and, sure enough, the neurons were retuned to
respond to the shocking tone.
The auditory cortex is not the only area of the brain associated
with music. A vivid example cited in the Scientific American
article is that of a woman with a damaged temporal lobe of the
brain. The woman was normal in the sense that she had no
difficulties connected with intelligence, language or memory.
Yet, she was severely challenged musically. She could not
recognize or distinguish between any music, whether it was old
or new to her or whether the melodies were similar or completely
different! In spite of this, her emotional reactions to different
types of music were perfectly normal. Conclusion: the temporal
lobe is essential to the comprehension of melody.
Are there certain pieces of music that make you feel absolutely
euphoric? Anne Blood and Robert Zatorre of McGill University
ran imaging experiments on the brains of musicians listening to
such pieces and found that the brain lit up in the same reward
regions as those related to food, sex and addictive drugs. Could
that indicate that one could diet by listening to the right kind of
music instead of grabbing that extra doughnut?
All this work on the brain is great but how do you explain 12-
year-old Jay Greenberg? Jay, who already has composed 5
complete symphonies, has been on a full scholarship at Juilliard
since he was 10! Some are comparing him to Mozart. I saw this
child prodigy interviewed by Scott Pelley on 60 Minutes a
couple of weeks ago. When Pelley asked him how he composes,
Jay replied that it was all in his head, fully written and that he
essentially hears the full orchestral version in his head. All he
has to do is write it down, scoring the work for the different
instruments in the orchestra. Sometimes it seems that he can
hear more than one composition at once as though there are
multiple channels in his brain.
After watching the 60 Minutes segment on this child prodigy, it
was clear that all this work on the brain has barely begun to
scratch the surface of the remarkable properties and functioning
of this strange blob of gray matter.
NOTE: This column was posted on 12/15/2004 but disappeared until
re-posted on 12/17!! Gremlins?!
Allen F. Bortrum
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