Christine Thomas,
Mezzo Soprano
"I love to sing-a, about the moon-a and the June-a and the spring-a!"
----- Original Message -----
From: Gerry Stamey
To: Dave Martin ; Bob and Char Sigman ; David McCain ; Diane Lane ; Kirstin
Chávez ; Victoria Schultz ; Stefan Kutrzeba ; Judith Worbs ; Jason Budd ; Herb
Zellmer ; Carolyn Cooper
Sent: Saturday, December 07, 2002 6:52 PM
Subject: biological foundations of music
Paul McKay
The Ottawa Citizen
Monday, November 18, 2002
Sex. Chocolate. Caffeine. Champagne. Cocaine.
If none of the above turn your cranial crank, it's also likely that Mozart or
Alanis Morissette won't send shivers down your spine. And that your pulse rate
should be checked by a doctor -- because the human survival instinct is
hard-wired to the same brain circuits that process intense pleasure.
A team of researchers at the Montreal Neurological Institute, using the world's
most advanced brain-mapping machines, have found that the same neural clusters
that process the seductive pleasures of sex, chocolate and even hard drugs also
fire up for music.
There is also persuasive evidence that the brain tends to prune these neural
circuits for maximum pleasure the way a gardener cuts unproductive branches to
make a rose bush bloom. Music, it seems, may make the brain bloom best because
it literally electrifies, at lightning speed, a web of nerve paths in both
hemispheres of our cerebral cortex that connect the neural clusters processing
musical pitch, rhythm, harmony, melody, short term memory, long term memory, and
emotions. Now, for the first time, neuroscientists mapping the musical mind at
McGill University have confirmed that those music circuits also comprise the
inch-worm shaped clusters that process exquisite pleasures, including illicit
ones. But unlike other addictions, it leaves no hangover, drug habits, clogged
arteries, or sexual diseases.
Sound too good to be true? If it is, billions of brain cells, a $6-million MRI
imaging machine, and a leading cognitive neuroscientist are all wrong.
Robert Zatorre and his colleagues at McGill University have been heading studies
into the effects of music on the human brain for more than two decades. Deep in
the bowels of an old stone building on the McGill campus, they scan human brains
the way a geologist scans mineral maps, except they are tracing, in real time,
the topography of human brains while circuits and clusters of neurons fire.
They and their international colleagues have used sophisticated PET and MRI
scanners to peer inside brains to detect where pitch, melody, harmony and rhythm
are processed. The answer, it turns out, changes with the complexity and
composition of the music. There are distinct clusters of cortex that seem to be
responsible for each component of music, such as rhythm or harmony. Yet even the
simplest song heard or sung by a child sends showers of neural sparks across
both sides of the brain, linking each element of music to respective cranial
regions. Music also lights up the lobes where memory is stored, the clusters
where logic and speech are processed, the brain stem where sounds relayed by the
ear are filtered, and the cerebral throne of emotion.
The brain even processes harmonic and dissonant music in different neural
circuits.
For a landmark study published last year, Zatorre's McGill team created an
experiment with remarkable results. Ten students, each with advanced musical
training, were asked to select a favourite piece of music. Among the selections
were Samuel Barber's Adagio for Strings and Rachmaninoff's Piano Concerto No. 3
in D minor.
Each of the subjects was played an excerpt from their favoured music while they
were scanned for brain neuron firing, cranial blood flow, heart rate, EMG,
respiration and skin temperature. All 10 subjects were also played an excerpt
from another student's selection, a calibrated patch of ordinary noises, and a
passage of silence.
Sure enough, chills tingled down the students spines as they heard their
favourite music selections. Their other vital signs spiked upwards during 77 per
cent of the scans. But the real discovery came as the computer-linked
scanner/cameras took split-second snapshots through the multiple folds and
mounds of grey matter: Blood flowed to areas where neurons fired in galaxies of
electro-chemical energy bursts, but away from areas where brain neurons were
relatively dormant.
During the moments of musical euphoria, their cranial blood streamed to the
parts of the brain which previous, independent studies had isolated as the
places where sex, chocolate, champagne or cocaine can produce ecstasy. In
effect, 10 different cortex clusters burst into neural fireworks, creating the
familiar spine-tingling chills of pleasure. Equally intriguing, the blood flowed
away from brain cells associated with depression and fear.
"We have shown that music recruits neural systems of reward and emotion similar
to those known to respond specifically to biologically relevant stimuli, such as
food and sex, and those artificially activated by drugs of abuse," Zatorre
concluded in his published paper. "This is quite remarkable, because music is
neither strictly necessary for biological survival or reproduction, nor is it a
pharmacological substance."
Our brain neurons, says Zatorre, are hard-wired for music -- from cradle to
grave. And the more we use 'em, the less we lose 'em.
"All normal children will spontaneously sing something like the Sesame Street
song," he says in his McGill office while fielding phone calls to book precious
time on an MRI machine -- which costs $400 per hour, and primarily is used to
scan patients. "That's a very sophisticated neurological feat. It means their
brains recognize the theme, and associate it with their favourite TV show. They
will try to sing it, on their own. They may not reproduce it very accurately,
but it is recognizable. No one can teach them this, versus reading or math. Like
blind children learning to walk, they just do it when they are ready. It is
wired into our nervous system.
"The vast majority of people with no musical training can sing a song, and still
recognize a tune when it has been altered by a different key, instrument or
rhythm. That seems to be innate, something our brains are wired to do. And there
is no known culture which does not have some sort of music."
The Zatorre study followed earlier McGill probes into how harmony and dissonance
affect the neural clusters known to process emotions; where in the brain we
select key features of voices; how people process melodies; where musical pitch
and rhythm are processed; and where the mind's eye imagines and perhaps invents
music.
The brain's chief task, Zatorre concludes, is to keep astonishing itself. And
music may do it best.
"Music involves perception, memory, emotion, motor control, all the learning
aspects. It brings together a lot of different functions in a very coherent
way," says Zatorre, who is also an acomplished organist. "The brain wants
patterns to assemble but it also craves diversity, so a very important part of
music is surprise. And you can only be surprised if you anticipate - and don't
assume a random series of notes."
"The best music plays with that tension. If it goes too far in lacking
structure, it collapses into random sounds. Then your nervous system loses
interest; it just becomes noise. If you go too far to the other extreme, where
everything is completely predictable, soon you'll never play it again. The brain
likes to be challenged."
Zatorre and Isabel Peretz, a noted neuropsychologist at the University of
Montreal collaborate on complementary studies, and assembled a newly published
compilation of academic reports called The Biological Foundations of Music. It
summarizes much of the past decade's international research into the origins of
human music, particularly neurological evidence uncovered by brain scanning
technology and related experiments.
That text is augmented by continuing studies of the musical mind at universities
in Montreal, Toronto, Boston, California, and Europe. Published in scientific
journals and posted on university and medical school Web sites, they reveal
alluring evidence that:
The brains of musicians, especially those who begin dedicated practice before
age 7, have larger neural clusters involving music processing such as the neural
region that directs a violinist's hands -- sound perception and discrimination
begins before birth, and neurons begin firing before language skills develop in
infants, aided by parental cooing and lullabies.
The brain selects the most efficient neural highways to process music, closing
those that create musical traffic jams and opening those that make sounds flow
faster. The more these circuits are used, the more their musical range and
capacity expands. Both hemispheres of the brain share music processing functions
and are connected by a key neural bridge, the corpus callosum, which unites
specialized regions sending complex musical data at blinding speeds. Recent
studies indicate the 100 million-nerve conduit is up to 15 per cent larger in
musicians trained since age eight.
Music acts as a specialized fuel to fire millions of brain nerves that otherwise
remain dormant or undeveloped. As the brain burns musical fuel, it creates
chemicals that produce contentment and even ecstasy. Recent studies of choir
singers show elevated levels of these after performances.
"The PET and MRI scans only became available in the last two decades," says
Zatorre. "They have really revolutionized the whole field of cognitive
neuroscience -- the study of the brain mechanisms that allow us to perceive and
think and act and reason and remember. They allow us to probe the workings of
the brain in normal people. Before we had to rely exclusively on those with
brain damage."
Asked to summarize what brain circuits are deployed when humans process music,
Zatorre momentarily jettisons his meticulous scientific caution and flashes a
grin.
"Everything from the neck up." he answers.
Paul McKay is a Citizen reporter. More music and photos for this story, and
previous stories in this series, can be seen at
www.enchantedear.com.
More details about the Zatorre/McGill studies can be found at
www.zlab.mcgill.ca
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