Music and Neuroscience
Music activates so many parts of our brain that it's impossible to say that we have a center for music the way we do for other tasks and subjects, such as language. When we hear a song, our frontal lobe and temporal lobe begin processing the sounds with different brain cells working to decipher things like rhythm, pitch, and melody. Many researchers believe that most of this action happens in the right hemisphere, though others say reducing music to a right brained or left brained activity isn't possible. Regardless of where the brain activity takes place, it does seem to differ based on a whole host of factors, including how much experience with music the person has, whether he or she is hearing live or recorded music, and whether or not the music has lyrics.
If the song has lyrics, then the parts of the brain that process language, Broca's and Wernicke's areas, kick into gear. Researchers have found that songs can activate our visual cortex, perhaps because our brain tries to construct a visual image of the changes in pitch and tone. Songs can trigger neurons in the motor cortex leading you to tap your foot and boogie. Your cerebellum gets into the act by trying to figure out where a piece of music will go next, based on all the other songs it's heard before. - This is why sometimes you can hum along to a song that you have never heard before and your generally right on key and can predict the chord changes and follow the map of the song.
Hearing a piece of music is also tied to memories: If this is the song that was playing during a first kiss, then the medial prefrontal cortex, where memory is stored, lights up. Since this is one of the last brain areas to fall prey to the ravages of Alzheimer's disease, researchers have found that people with the condition can remember songs from long ago, even when they can't remember what they did yesterday.
While many parts of the brain are involved in deciphering a piece of music, brain imaging scans appear to demonstrate that our emotional reaction to music also takes place in the brain.
In a study of a woman who had damage to her temporal lobe, researchers found that while the woman was unable to distinguish between melodies, she was still able to have the emotional reaction that you might expect from hearing happy or sad melodies [source: Weinberger]. Further imaging studies have shown that music we'd expect to be happy, activates the reward centers of the brain, releasing dopamine, so that music gives us the same hit of happiness that we would get from a piece of chocolate, sex, or drugs.
Does that mean your radio could take the place of an antidepressant?
The neurological studies of music on the brain seem to indicate that we're hardwired to interpret and react emotionally to a piece of music. Indeed, this process starts very early on. One study found that babies as young as five months old reacted to happy songs, while by nine months they recognized and were affected by sad songs [source: LiveScience]. Physiological states brought on by music only intensify as we grow. Happy music, usually featuring a fast tempo and written in a major key, can cause a person to breathe faster, a physical sign of happiness [source: Leutwyler]. Similarly, sad music, which tends to be in the minor keys and very slow, causes a slowing of the pulse and a rise in blood pressure. That seems to indicate that only happy music is beneficial, but those that know the value of a good cry or a cathartic release may find that sad or angry music can bring about happiness indirectly.
Knowing that music has this impact on the body may eventually influence treatment and care for a wealth of patients. For example, music has been found to boost the immune systems of patients after surgeries, lower stress in pregnant women and decrease the blood pressure and heart rate in cardiac patients, thus reducing complications from cardiac surgery [sources: Lloyd, Wiley-Blackwell]. Researchers at Cal State University found that hospitalized children were happier during music therapy, in which they could experiment with maracas and bells while a leader played the guitar, than during play therapy, when their options were toys and puzzles [source: Hendon and Bohon]. Music therapy has also proven to be more effective than other types of therapies in patients suffering from depression, and it's been shown to lower levels of anxiety and loneliness in the elderly [sources: Parker-Pope, Berger].
You don't have to be sick though, to benefit from the reduced stress and increased happiness that music can bring. Live music may be the most potent happiness trigger because it provides a way to forge social bonds. When you get in a room with people who like the same thing you do, you might create more friendships, a proven factor in the search for happiness.
However, it's worth noting that too much music could be too much of a good thing. Since music triggers reward systems in our brains much like drugs do, music could also become an addiction that becomes impossible to feed. Having music around us constantly -- from department stores to elevators to our headphones -- could numb us to its effects. Unplugging that iPod every now and then might just help your favorite song sound sweeter later on.