The Science of Music
The Science
How Music Affects the Human Brain
When sound enters the ears, they are converted into electrical signals. These signals are transmitted via the auditory nerve to the auditory center of the brain, where sounds are processed.
It has been observed, however, that music stimulates other regions of the brain as well. Some of the most frequently affected regions are those involving emotion and memory. The areas associated with motor skills are activated as well. (1)
MEDIAL PREFRONTAL CORTEX
Science has also found that the medial prefrontal cortex of the brain, located right behind the eyes, is the link between music, memory, and emotion. fMRIs showed that individuals medial prefrontal cortex lit up when a song from their childhood, especially one that was connected to a specific emotion or memory, was played.
Similarly, the medial prefrontal cortex is associated with musical creativity. While improvising, a jazz musician's prefrontal cortex turns on. Yet, this is not observed when playing memorized scales. Meanwhile, the regions of the brain involved in self-monitoring turn off during improvisation. (1)
Charles Limb has also studied the concept of the brain's involvement in jazz improvisation. He specifically looked at the differences in brain activity between the performance of a memorized piece and a spontaneous improvisation. The fMRI scans showed that the medial prefrontal cortex (in red on the right) increased significantly in activity, while the lateral prefrontal cortex (in blue on the right) decreased in activity. The lateral prefrontal cortex is associated with self-monitoring and the medial prefrontal cortex is associated with self-expression. Limb thus hypothesizes that in order to successfully improvise, the brain must lower or turn off its self-monitoring and increase its self-expression. This would allow for the individual to play any musical phrase that came to mind, without the brain shuttin down the idea. Limb also found that during improvisational trade offs, the left inferior frontal gyrus, or the Broca's area, showed heightened activity. This area of the brain is also associated with language, thus suggesting that when musicians improvise back and forth it is a conversation employing music as the language.
Limb is now performing similarly structured experiments using free style rap, in place of jazz improvisation. His current findings juxtaposed with those from the jazz improvisation experiment generally show that brain activity is significantly increased when one is improvising compared to one that is reciting a memorized passage.
MUSIC AND MEDICINE
DEPRESSION
Ji-Hae Park is a professional violinist. She experienced a season of her life where she suffered from severe depression. Through classical music and her violin, she found not only happiness but hope. She progessively was healed by the power of music and the production of this music. The expression of emtion in the music that she played allowed her to begin to experience happiness again and rise from her depression. Though there was no quantitative or formal science or research done in this case, this is an example of a real world observation of the sheer power that music has on our brains and our bodies.
MUSIC THERAPY
Robert Gupta studies the connection between music and medicine. Music therapy itself is a treatment for mental illness and disorders that has been present for hundreds of years. Gupta, specifically, has studied some of the effects music can have on an individual who has experienced head trauma.
One example that Gupta presented in his findings was Congresswoman Gabrielle Giffords at the early stages of her recovery from an awful bullet that had enetered her left hemisphere and destroyed her Broca's area, the speech center of her brain. During therapy, she was unable to verbally express herself in anyway. However, once her therapist attempted to use music as a therapeutic option, Giffords opened up. She very clearly enunciate lyrics, "Let it shine, let it shine, let it shine", to a familiar tune.
Dr. Gottfried Schlaug, a lead neuroscientist in this specialty, found that many stroke patients with aphasia, who were unable to form three words phrases, could sing lyrics to a song. After 70 hours of intensive singing lessons, Schlaug found that music was able to rewire the brains of his patients, creating a speech center in their right hemisphere to compensate for the left hemisphere's damage. He also found that patients with Parkinson's tremors steadied while listening to music.
TUNE DEAFNESS
This disorder is marked by the difficulty in differentiating between musical tones. Interstingly, the tune deaf can register a mistake in a familiar tune. They do not, however, realize that it was a mistake. Their brains failed to produce the second signal needed to achieve this. (1)
MOZART EFFECT
J S Jenkins found, in an NIH experiment, that after listening to 10 minutes of Mozart's music, spatial-temporal reasoning improves. This result is supported by most, but not all researchers. Mozart's music has also proven beneficial to epilepsy patients. (2)
AMUSIA
Amusia refers to the neurological disorder who have lost the ability to process complex music. The research done about this condition is significant because of the understanding gained about melodic and temporal perception. Local and global auditory information processing is required for both melodic and temporal perception, where pitch intervals are local and melodic contours are global. Rhythm is percepted locally, and generally processed in the left hemisphere. Meter is percepted by a global mechanism.
Similarly, there are local strategies for the perception of duration and temporal distance between auditory events (known as rhythm) and global mechanisms for the perception of metre (the temporal variance of recurrent pulses providing durational units by which we recognize a waltz or a march23,24). Temporal structures of music, rhythm in particular, are preferentially processed in the left hemisphere. In relation to the processing of pitch, lesions on the right side impair perception of melodic contour, whereas unilateral lesions impair perception of pitch intervals.(3)
BRAIN STRUCTURE
Catherine Y Wang and Gottfried Schluag conducted a series of experiments through the National Institutes of Health. They found that music making leads to changes in the poly-modial integration regions, which is hypothesized to lead to alterations in various task performanced. Specfically, instrumental music making has lead to structural and functional changes in the intraparietal sulcus. These observed adaptations have show positive effects on mathematical performance due to the neutral resources near the IPS, which are strongly associated mental manipulation of symbols. Also music making and training from a young age aid in cognitive development and the possible development of absolute pitch. (8)
