What Happens When the Brain Plays a Musical Instrument?
Playing a musical instrument: One of the most challenging human activities
Playing a musical instrument involves multiple components of the central (brain and spinal cord) and peripheral (nerves outside the brain and spinal cord) nervous systems.
As a musician plays an instrument, motor systems in the brain control both gross and fine movements needed to produce sound. The sound is processed by auditory circuitry, which in turn can adjust signaling by the motor control centers. In addition, sensory information from the fingers, hands and arms is sent to the brain for processing. If the musician is reading music, visual information is sent to the brain for processing and interpreting commands for the motor centers. And of course, the brain processes emotional responses to the music as well!
Music training can structurally alter the human brain
Practicing a musical instrument can lead to numerous structural changes in the brain after only 15 months of training in early childhood. These changes correlate with improvements in certain motor and auditory skills.
One area where these structural and functional changes occur is in the hippocampus (shown above), an area of the brain involved in learning and memory. A process that is critical for learning and memory in the hippocampus is neurogenesis – the formation of new neurons. Musical practice may therefore enhance neurogenesis linked to improved learning and memory activity.
People with “amusia” may have less white matter in some regions of the brain compared to normal subjects
Amusia is a severe form of tone deafness that prevents people from forming basic musical skills and which can alter how people perceive music. A number of studies have indicated that the white matter in people with amusia may be abnormal. White matter is filled with myelin. Since myelin functions by increasing the speed at which nerve impulses travel, these findings suggest that to process music neurons must have proper myelination. The image on the left is an MRI showing areas where white matter volumes are different between someone with amusia and a control subject.
Piano (and other instruments) practice increases myelination
The white matter of the brain is made mostly of myelin, which surrounds the axons of neurons to increase the speed of nerve impulses. In this study, a special form of MRI was used to measure the amount of white matter found in the brains of people who practice piano on a regular basis. The findings suggest that practicing the piano is an effective way to enhance the structure of white matter. Shown here highlighted in color are two areas of white matter in the brain that were affected by piano practice: the internal capsule (a, b) and the corpus callosum (c), the white matter that connects the two hemispheres of the brain.
Physiological evidence that music practice increases the number of synapses in the human brain:
Remember that synapses are the chemical connections between neurons that form circuits, and that synapses are made during the course of learning. One way to get a hint of synaptic activity in the brain is by measuring “paired associative stimulation” (PAS) which involves stimulating neurons via a procedure called transcranial magnetic stimulation (in this case for 25 milliseconds). As shown here, 11 professional musicians had greater activity than 8 age-matched non-musicians. These data suggest that musicians have increased numbers of synapses in the part of their brains that control motor functions.