A pianist’s neurons
On Sunday morning I was watching Cara DeHaan, who wonderfully edits my columns, play the piano for our worship service. She has musical talent I can only appreciate with my ears, not duplicate with my hands or mouth. While listening to her play, it struck me, given the way the body works, how miraculous is the ability to play the piano (or, for that matter, any musical instrument).
Here’s what happens for our fingers to move. A part of our brain (usually the primary motor cortex, on the opposite side of the body from the fingers we want to move) sends a signal to the spine, telling it to activate or inhibit particular neurons. This signal then travels from the spine down towards the end of the arm. It causes one muscle in our finger to contract and usually an opposite muscle to relax (by inhibiting the contraction neurons).
The situation is more complex: in order to move our fingers exactly as desired, to know exactly which muscles need to be contracted and relaxed, the brain needs to know where the fingers are in space and how they are positioned. This requires feedback from the hand and fingers and may involve using the signals from our visual system in conjunction with this feedback to determine what is needed to carry out a particular task, like hitting a particular piano key. (Cara pointed out that a pianist also has to read the music and translate the notes into motor commands, an added layer of complexity.)
What makes the task of piano playing even more interesting is that it takes the signals from the brain some time to get to the muscles that control the fingers. Neural signals do not move that quickly (the exact speed depends on a number of factors like the size of the neuron and if it is “insulated”). There are also a number of junctions between neurons (synapses) that have to be crossed, which slow the signal too, because at these synapses neurotransmitter molecules have to activate the next neuron. Thus there is a measurable span of time from the point at which the brain decides to move the index finger down (on a piano key) and the point at which the finger actually moves.
Programmed
Music, however, also is a matter of timing. The time between notes can be very short, especially when played presto, and music requires that the rhythm be maintained. Decisions about the next finger move may have to be made before the last one has been completed. Thus, playing music may require that our brain work ahead of the feedback that the sound of the piano will give us. This ability can be obtained only through practice. I’ve been told that piano players learn to play music slowly and program each note individually. With experience and repeated uses of the particular commands, the notes can be combined into units that the brain programs to play without conscious individual note control (like letters become words). This repetition works especially because multiple pieces of music often make use of the same sequence or combination of notes. Piano players practice runs and scales partially because their brain has to be programmed to play the notes as a sequence without time to correct midstream.
Another common example of this skill can be seen in typing. With practice typists become faster and can type certain words almost automatically. The difference between typing and piano playing, however, is that with typing the speed is not essential to the quality of the outcome; it is merely advantageous to type faster, and for all of us the skill becomes more efficient with experience.
In contrast, music in which the musician’s brain is individually programming every note can be painful to listen to, as every parent of a budding player is aware. It is the repeated execution of a sequence of once conscious, individual commands that transforms them into a combined unit that can be executed with a single unconscious command. This repeated execution is what makes skilled music playing possible and makes listening to Cara and our other skilled musicians play on Sunday morning in our church the joy that I experience.
As you worship and listen to the musicians in your congregation play for you, or perhaps play yourself, give thanks to our Lord for such talent and the ability to use the body God has given us to make rich music to praise him.
