Sunday, August 15, 2010

more than a feeling

Sciencenews | “It’s like the brain is on fire when you’re listening to music,” says Istvan Molnar-Szakacs, a neuroscientist at the University of California, Los Angeles. “In terms of brain imaging, studies have shown listening to music lights up, or activates, more of the brain than any other stimulus we know.”

That music can activate so many brain systems at once is the reason it packs such a mental wallop. It exerts its most profound effect in the brain’s emotional core, the limbic system. There, music changes virtually all areas of the brain responsible for regulating emotion, as neuroscientist Stefan Koelsch of Freie Universität Berlin describes in the March Trends in Cognitive Sciences. Music automatically engages areas essential to pleasure and reward. So much so, in fact, that the same pleasure centers in the brain light up whether you’re listening to a favorite tune, eating chocolate or having sex.

These dramatic effects make music a valuable instrument for probing the brain’s emotional circuitry. Koelsch and others are now using music as a tool to see how the brain processes a wide range of feelings such as sorrow, joy, longing and wonder. (Click here for a link to audio clips from some of Koelsch's experiments.) Some of these emotions, so easily felt in response to music, are otherwise difficult to evoke in an experimental setup. Other researchers are using music to explore how children with autism spectrum disorders process emotion. While these kids often have difficulty recognizing how others feel, they readily respond to the sentiments of a song.

Using music to study and stimulate the brain’s emotional circuits may lead to new therapies for treating a wide range of emotional disorders, including depression, anxiety and post-traumatic stress disorder, scientists say. By understanding how music activates and coordinates the various emotional mechanisms in the brain, scientists may find ways to rewire a brain affected by illness or injury, or provide a work-around for damaged or underperforming brain regions.

Despite the long list of potential benefits for health and happiness, Koelsch contends that the deep, complex experience that music delivers is primarily a social, rather than an individual, phenomenon (see “Not just a pleasant sound,”). Ages before people walked around with little wires in their ears to listen to music anytime, anywhere, tunes piped on flutes and reeds were probably used in tribal rituals to unify hunters and warriors about to do battle. Today, music helps pull people together at weddings, funerals and countless social events.

Music is universal. It occurs in all human cultures in some form, and extends deep into human history. Archaeologists have unearthed flutes made of bone that date back nearly 40,000 years. And scientists say that long before someone went to the trouble of carving a flute, humans banged out tunes using sticks and stones. Given that music gave early flutists and their fans no direct biological advantage over rival creatures — sweet melodies couldn’t put food on the stone slab or guarantee grandchildren — researchers have long wondered why humans developed the capacity to perform and enjoy it.

Though music may not have evolved for survival purposes, modern-day imaging techniques reveal that it can have the same effects on the brain as many survival-related activities. In 2001, neuro­scientists Anne Blood and Robert Zatorre of McGill University in Montreal asked people to listen to music deemed so moving by these participants that it “sent shivers down the spine.” Blood, now at Harvard, and Zatorre showed that music activates neural systems of reward and emotion similar to those stimulated by food, sex and addictive drugs.