Looking back on my childhood, one of the most consistent themes was music.
My mom is a public school music teacher, so I grew up hearing the melodies of a singing voice, the chords of a freshly tuned piano, and the harmonies of a small chamber group reverberating through the halls of our home. Almost as soon as I learned to read words, I also learned to read music, sifting through flashcards as my mom drilled into my brain the memory of musical notation for pitches both low and high. And by the time I was in preschool, I was performing duets with her on the piano for family and friends.
When I entered the fourth grade and had the opportunity to join the orchestra at school, I gladly welcomed the opportunity to learn to play the cello. The idea of producing sound by moving a bow across a string fascinated me, and the position that cellists’ bodies assumed while they were playing seemed comfortable yet powerful - an intriguing command of a simple piece of wood.
The first time I held a cello between my knees, with its shoulders resting on my chest, the movements felt awkward and forced. How exactly was I supposed to move my right arm in grand gestures while my left arm stayed fixed in place, with only the fingers moving? How could I possibly move the bow at the correct speed when each note had its own duration? How should I learn to press the strings down when some of my fingers were stronger than others? And how would I ever read the music at the same time?
Now that I’ve been playing the cello for 14 years and counting, these tasks come to me so naturally that I don’t even have to consider them. And as a neuroscientist, I am conveniently poised to notice and reflect on how my brain got me to this point. How was I able to learn these complex feats of motor control? And how is music even perceived in the brain, anyway?
It’s quite amazing that my brain has transformed me from a fourth-grader fumbling through my first time touching a cello, to a seasoned musician who can play pieces both old and new with ease.
Music and all sound, in general, is a series of vibrational waves traveling through the air. The vibrations themselves do not create the perception of sound, but rather it is our brains that have learned to interpret these vibrations in an organized way, parsing sound into components such as frequency (pitch), amplitude (volume), and timbre (specific sound quality or identity).
When vibrations from the air reach the ears, a cascade of activity springs into action inside the ears, sending information to the brain. First, the eardrum begins to vibrate in response to the sound waves entering the ear canal. The movement of the eardrum causes small bones in the ear to vibrate, and these vibrations further cause the movement of small cells called hair cells. These cells are not actually hair but are so named because of their long and thin hair-like appearance.
When these hair cells vibrate, they rub against other membranes, causing these membranes to vibrate along with the hair cells. This vibration is then translated into an electrical signal that activates the auditory nerve, which travels from the ear to the brain. This electrical signal further activates other important brain regions that help us process the sound in more depth. These higher-level regions help us piece together each fragment of sound: each pitch, each duration, and even the location of each sound’s source. When added together, these components help us perceive and understand the sound of an instrument playing our favorite song.
That’s a lot of complexity just to hear and make sense of a single note! But the sound is not the only thing your brain has to keep track of when you play an instrument. Thinking back to the awkward early days of my cello experience, it’s clear that learning to play an instrument also requires refined motor skills, which must be learned over time.
The motor refinement that occurs when improving on an instrument is an example of how the brain can change over time to support learning. Not only does this occur in response to learning new facts (what neuroscientists call declarative memory), but it also occurs when learning new tasks that involve moving the body (what neuroscientists call procedural memory). Skilled musicians have a highly developed procedural memory for how to play their instruments, and they further refine these skills over time, changing their brains in the process.
The idea of producing sound by moving a bow across a string fascinated me, and the position that cellists’ bodies assumed while they were playing seemed comfortable yet powerful - an intriguing command of a simple piece of wood.
But there are some surprising findings of musicians’ brains that go beyond just the ability to learn a new skill. For example, people who play string instruments, such as the cello or the violin, have a greater portion of their brain devoted to the sense of touch on the left hand than people who don’t play these instruments. Because string musicians must press down the strings with the fingers on their left hand, this evidence suggests that by using a particular part of the body to touch something more often, the brain actually changes to support the new skill that the musicians are learning. Fascinating!
Besides the way the brain changes due to sensory input, the brain also changes as a musician becomes better at the motor control required to play their instrument. As a musician repeatedly performs a particular movement, such as gliding a bow from side to side across the strings, the brain cells that are responsible for coordinating that movement become more strongly connected. Over time, the increasingly strong connections between those cells make this movement become less clumsy and more coordinated, facilitating the seemingly effortless motor skills of practiced musicians.