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بعون الله سيكون هذا المنتدى قبلة لللأساتذة و الطلبة للتعليم و التعلم


    Why Do we Live Music

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    Lilkay32

    عدد المساهمات : 2
    تاريخ التسجيل : 13/06/2009
    العمر : 25

    Why Do we Live Music

    مُساهمة  Lilkay32 في الخميس يونيو 18, 2009 10:31 pm

    We Just Can't Get that Song out of Our Heads...
    It is cruel, you know, that music should be so beautiful.
    It has the beauty of loneliness of pain: of strength and freedom.
    The beauty of disappointment and never-satisfied love.
    The cruel beauty of nature and everlasting beauty of monotony.


    With rare exceptions, the brain has a deep affinity for music. As an example, one evening in 1995, a Montreal real estate agent and his wife went out for a romantic dinner. It was their wedding anniversary. They felt fortunate. The husband had suffered a minor stroke a few years earlier and had recovered. In neurological test after test, his reading, speech, memory and motor functions seemed to be normal. He had even returned to work and made some lucrative deals. During dinner, his wife noticed a violinist playing for restaurant patrons. "Let's get him to play our song," she suggested.

    When the song ended, the agent's wife noticed a strange expression on her husband's face. The playing, he complained, had been awful. "The tune was so distorted I couldn't even recognize it," he said. "No, it was beautiful," she countered. After an argument, he realised that all music now sounded strange. The stroke had wiped out his capacity to comprehend the patterns of tone and tempo, pitch and rhythm we call music.

    His case baffled doctors.

    "It's not like this guy had gone deaf or he could no longer perceive sound, because he could hear other sounds just fine, particularly speech tones," says Robert Zatorre, a professor of neuroscience at the Montreal Neurological Institute. Quite simply, he had become amusical.

    What is more remarkable, perhaps, is how seldom such a problem occurs. The human brain appears to come equipped with its own stereo receiver. No known human culture has ever lived without music. Ancient bone flutes have been found in France and Slovenia, some are as old as 53,000 years and they still make a beautiful sound. Long before our ancestors scrawled ochre images of buffaloes on cave walls, they sang. Music may even be older than speech. A mother's lullaby is among the first human experiences, and a familiar song is usually one of the last. "The last memories that we keep in our minds are for music," says Christo Pantev, a neuroscientist at the University of Toronto's Rotman Research Institute. "People with Alzheimer's disease may forget names and people and everything else, but they still recognise songs to the end. It's incredible."

    A source of enduring mystery to scientists is why humans create and love music. Do our brains have a module - call it a music box - designed to process music? And if so, why did Mother Nature, ordinarily so frugal, equip us with the technology to recognise the Barney (the purple dinosaur) theme song when we hear it? "This is something our nervous system is predisposed to do," says Zatorre. "You don't have to teach a two-year-old to recognise his favourite song when it comes on TV. It will just come naturally."

    Neuroscientists have spent decades probing how the brain understands words. Remarkably, only a handful of researchers are working on how we perceive and create music. "What we can say for certain is music and the brain have evolved together," says Dan Letivin, a former music producer who is now a professor of psychology at McGill University in Montreal.

    Yet while music has evolved, human brains have not changed since the ancient flutes were first played. Mutations and adaptations take about 500 centuries to become encoded in our DNA, an interval known as evolutionary lag. "However our brains are now, they're that way because of the way life was 50,000 years ago," says Letivin. "So when you talk about how music might have shaped us, it's the music we were listening to 50,000 years ago. Beethoven and the Beatles haven't had enough time to influence the genetics of our brains. They have certainly influenced the development of our brains as we've listened to them over our lifetimes, but they haven't influenced the genome yet."

    It seems almost all the researchers who study the brain's response to music play instruments themselves. A few even compose music for their experiments. In the early 1970s, Robert Zatorre was working his way through a music degree at Boston University, playing the organ at weddings and funerals in a local church. "I'd get $25 a shot," he laughs. "That was a lot of money back in 1974." Like many musicians, Zatorre had a fondness for numbers, so he also took some physics courses, later switching to psychology and biology. At graduation, with a psychology degree in one hand and a music degree in the other, he decided to pursue science. "Practically speaking, I thought I would earn a better living as a psychologist," he said. In the end, though, he combined his two loves, and found a laboratory that let him study how the brain recognises music. "People would say, why are you studying music?" he says. "That's not important. You should be studying speech, or memory or reasoning." For a while, he disguised his work in highfalutin jargon, calling it "auditory pattern processing."

    But the tide has turned. Neuroscientists now recognise that music is a rich source of information on how the brain works. Music has many cognitive elements: emotion, patterns, motor aspects of performance. Jazz drummers, such as Buddy Rich and Gene Krupa, could keep four separate beats - both hands and feet - in time with a complex melody, improvising on the fly. Orchestral musicians must memorise enough notes to melt a tuning fork - Tchaikovsky's Romeo and Juliet Overture alone has 20,000 musical notes. Talk about brain work!

    In the late 1970s, Zatorre came to the Montreal Neurological Institute to study subjects who had undergone surgery for epilepsy. The procedure, developed by the institute's founder, Wilder Penfield, involves removing part of the brain's temporal region, the site of the auditory cortex. "One of the first things we noticed was that when the [surgical] damage was on the right [brain hemisphere], the problems with tone perception were much greater than when the damage was on the left," Zatorre says. "And this is actually the reverse pattern that had been found ... with speech sounds. So although there are similarities between speech and music, they seem to depend on partly different brain regions." This shed light on some musical brain twisters. For example, in 1953, at the age of 51, Soviet composer and teacher Vissarion Shebalin suffered a stroke. A gifted and prolific musician, he found himself partly paralysed on one side. To his horror, the stroke damaged his ability to speak, although his vocal cords were not harmed. Yet Shebalin's "voice" didn't die. Before his death 10 years later, he composed more than 20 complex works, including his beautiful Fifth Symphony. Shebalin and the Montreal real estate man inhabited two solitudes of sound; words failed one, music died for the other.

    The brain's ability to remember and produce music is often astonishingly resilient, even after the brain has been seriously damaged. "The Mendelssohn violin concerto was very, very important for my father because that's the piece ... that probably saved his life when he was in the camps, at Auschwitz," says Pinchas Zukerman, the brilliant violinist and conductor of Canada's National Arts Centre Orchestra. The elder Zukerman, also a violinist, was forced to play for the Nazi camp commandante on Sundays. The performances may have spared him from the gas chambers. "So the Mendelssohn concerto was important to him in the survival sense, besides the fact that he loved it," says Zukerman, who was born in 1948. "I remember him talking about it and playing it with me when I was a kid." But in 1969, the elder Zukerman suffered a stroke that paralysed his right arm - his bow arm - and damaged his power of speech. One day, several years later, Zukerman was having lunch with his father in Israel, and happened to bring his violin.

    "I said to him, in Yiddish, of course, 'Listen, do you want to play the Mendel concerto?' " recalls Zukerman. "He looked at me like I was crazy and said, 'I don't have the right hand.' But I said, 'Hey, I'll do the right hand.' " Gingerly, his father picked up the violin with his undamaged left hand. He hadn't held a violin in years, but the stroke had not diminished his musical memory. Pinchas stood behind him, holding his father and the bow. After two or three times, the elder Zukerman offered his son a look that said, Hmmmm, I can still do it. "It was unbelievable. I could not believe it. It shows how close we are, how connected we are to that stupid instrument." The image is vivid. Two generations, one using his right brain hemisphere, the other his left, neurons firing in harmony.

    In the early 1990s, when Zatorre began using magnetic resonance imaging (MRI) to scan brains, his fellow Montreal neuroscientist - and guitarist - Isabelle Peretz approached him to look at her patients. Like the real estate man, these patients had suffered strokes and could no longer grasp music. Peretz called the disorder amusia. Zatorre, who had never heard of such a problem, was deeply skeptical. "I didn't think this could really be so," he recalls. "She said, 'Here, test them. Tell me what you think'." Sure enough, the patients were amusical. But instead of damage to just the left or right brain, MRI scans showed the amusical patients had damage to the auditory cortex on both sides of the brain. Was there a music box after all?

    The findings got Zatorre and Peretz wondering. What about people with no stroke damage? Could you be born tone deaf? One of the most famous examples might be Florence Foster Jenkins, the unforgettable American singer of the early 20th century. The wealthy diva belted out Brahms and Vivaldi with great vigour and utter tunelessness, once renting out Carnegie Hall for a performance. Late in life, she remarked, "Some may say that I couldn't sing, but no one can say that I didn't sing."

    The scientists placed an ad in a Montreal newspaper seeking people who considered themselves tone deaf. Of the 37 off-key respondents, the most clear-cut case was "Monica," a middle-aged nurse with an IQ of 111 and a solid tin ear. Poor Monica. She had tried her best. "In Quebec, it's rather common to be enrolled in church choirs, so she did participate in those choirs, and she was told, of course, not to sing," Peretz later remarked. The choir directors told Monica to open her mouth, but keep silent. Attempts to play in a band met with the same disheartening end. The experience was so dismal, she confessed, that music now just gave her a headache. In acoustic tests, Peretz found Monica could not recognise melodies or changes in rhythm or pitch. Most people - even babies - can do better. Yet despite careful MRI scans, Peretz and Zatorre could find nothing unusual about Monica's brain. Where was the missing music box? "We couldn't find anything," says Zatorre. "But that doesn't mean there's nothing there."

    The MRI scanner can miss many subtle details, he explains, including how neurons are connected to one another. He is firmly convinced scientists will find out why Monica is tone deaf. "There must be something there," he says. "There has to be."

    Ironically, people who cannot hear a thing may be better at perceiving music than Monica. The deaf have a remarkable affinity for music, and even losing one's hearing is no barrier to tapping into the neural signals in the brain where music is generated. In a 2001 study, researchers from the University of Washington showed deaf people have brain activity in the auditory cortex, suggesting their brains rewire themselves to process sound vibrations. Deaf people enjoy music and can sense melody and rhythm, often holding a balloon in their fingers to amplify the vibrations. "It's not clear what they can perceive, but it's clear that they enjoy it," said Dean Shibata, a University of Washington researcher.

    Music is sound, but research has shown it might be light as well.

    Herv Platel and Jean-Claude Baron of the University of Caen in France scanned the brains of volunteers with positron emission tomography (PET) to see how they responded to changes in musical pitch. To Baron's surprise, areas of the visual cortex known as the "mind's eye" lit up the computer screens. McGill University researchers found the same phenomenon in the mind's eye of pianists. Does the brain store music as images? Recently, Zatorre and his colleague, Anne Blood, showed that when people experience the "chills-up-the-spine" sensation that some music elicits, it fires up the same brain circuits as those associated with the intense pleasure of sex, chocolate or even opium. Yet the reasons why humans love music are unknown.

    Some see it as critical to the survival of our species. "It's clear that humans wouldn't have made it if they didn't form tribes," says neuroscientist - and guitarist - Mark Jude Tramo of Harvard Medical School. "So how do you form a tribe? Where creativity and music come into play is to be human. To empathise with humans and share in the emotions of humans, to prepare to fight, to protect your territory, for procreation, you'll always find music. It's who we are."



      الوقت/التاريخ الآن هو الخميس أبريل 27, 2017 6:22 am