By: Nathan Michaels, Ph.D.
“Music can change the world because it can change people.” — Bono
The brain adapts. What isn’t used is lost, and what’s used constantly is bolstered. If a finger or entire limb is removed, the part of the brain responsible for interpreting its sensory information will shrink, being overtaken by regions responsible for intact portions of the body. If tactile stimulation increases—say your fingertips are constantly poked or prodded—the corresponding cortical areas will expand.
In 1995, Thomas Elbert—working at the University of Konstanz in Germany—led an experiment that applied this principle of adaptability to the brains of musicians. Given that musicians like violinists require a considerable amount of manual dexterity, and they constantly use their fingers to press down on the strings of their instruments, Elbert wondered if the brain regions associated with those areas would be different. Recruiting nine people that played the violin, the cello, or guitar, the researchers used magnetic source imaging to scan their brains.
Compared to non-musicians, the scans suggested that greater portions of the cortex were devoted to the fingers of musicians. What’s more, the earlier in life the musician started playing, the more the brain had changed. Elbert was the first to show that the brains of musicians were different than non-musicians.
Music is synonymous with the human experience. We organize sounds to decorate the silence of our lives. Music brings us together, helps us learn, and entertains us as we move throughout our day.
We use music to ignite societal change—the powerful and poetic “The Times They Are a-Changin” by Bob Dylan became an anthem of the civil rights movement in the 1960s, and Live Aid brought the attention and fundraising dollars of millions to support Ethiopian famine. We use music to change our mood—a peppy playlist to ramp up before a workout or a calming sonata to decompress. Considering how pervasive music is, perhaps its capacity for influence is no surprise.
In the decades following Elbert’s 1995 paper, dozens of studies have been published in various realms of neuroscience, all demonstrating the seemingly potent ability of music to elicit brain changes. Scientists focusing on structure showed changes in brain regions responsible for initiating and coordinating movement; in regions used for processing visual and auditory information; and in those carrying information to and from the cortex and between the two brain hemispheres. Those attuned to brain function observed changes in brain regions associated with recognizing and responding to novel time patterns and speech and music stimuli. And researchers tending to cognition—the area of neuroscience concerned with mental processes involved in gaining knowledge and comprehension—linked music playing to increased visual processing, attention, and visual and verbal memory.
Like Elbert, many of these studies tout a developmental hot spot. That is, the earlier you start playing an instrument, the more the brain changes.
Despite an expanding knowledge base, many facets of the link between playing an instrument and brain changes are in their infancy. One is causation. Are people with brains prone to structural and functional changes attracted to picking up an instrument? Or is practice alone enough to draw out an effect?
Another is the idea of the developmental hot spot. What happens if a 30-year-old picks up a guitar or learns the piano? What about a 40-year-old? Fifty-year-old? And for those of us interested in basic science, how does this all happen? What’s the underlying biology driving these structural, functional, and cognitive changes?
Drs. Orjan de Manzano and Fredrik Ullen of Karolinska Institute in Sweden have begun to decipher the issue of causation by studying identical twins. Twins share 100 percent of their genetic code. And because they often grow up together, they’re exposed to similar external factors. To a certain extent, studies with twins allow you to rule out genetic and environmental dispositions that could explain differences between two populations. At least more so than comparing two people with different DNA who grew up in different environments.
De Manzano and Ullen recruited 18 people—nine twins—from a larger group. Within each pair, one played the piano while the other did not. The brains of the twins were imaged, focusing on regions known to change as a result of musical practice (e.g., the cortex, cerebellum, and white matter). Analysis revealed significant changes in brain regions of the twins that were musically active. As the authors state, “These findings provide the first clear support that a significant portion of the differences in brain anatomy between experts and nonexperts depend on the causal effects of training.”
Developing research presented at the 2019 Cognomics Conference by Manal Alosaimi—currently a Ph.D. student at the University of Liverpool in the United Kingdom—suggests structural brain changes are not limited to a certain life stage. Fifteen men and women ranging from 20 to 57 years of age participated in a study where they learned to play the drums. None of the volunteers had any prior drumming experience.
Over six months, participants took lessons from a professional music teacher and were encouraged to practice daily. Drumming performance and progress were tracked throughout the study, and the brains of participants were scanned between eight and 13 times throughout the process. The study used a within-patient design comparing changes in particular brain regions within each participant from baseline (scans of the brain done before music lessons began). Analysis of the images identified changes in the inferior frontal and superior temporal white matter tracts.
This study is still ongoing. It will be interesting to see how it progresses and holds up under the scrutiny of peer review. It could benefit from a control arm (whether that be participants scanned at the same intervals who do not learn a complex task or a group learning a complex task that is not music). It would also be interesting to do a sub-analysis of the participants to determine how the changes in white matter structure are affected by age. Is there just as much change in the participants learning to drum at 57 as there is in the 20-year-olds?
Changes in brain structure may, at least in part, be due to a well-known protein called a brain-derived neurotrophic factor, or BDNF. BDNF was first isolated from pig brain in 1989 by Yves-Alain Barde and Hans Thoenen at the Max Planck Institute in Germany. Upon its initial discovery, BDNF’s similarity to the prototypical brain growth factor—nerve growth factor, or NGF—was noted. NGF is primarily involved in the growth, maintenance, proliferation, and survival of certain target neurons while BDNF functions in neuronal and glial development, neuroprotection, and the modulation of short- and long-term synaptic interactions (both of which are critical for cognition and memory).
BDNF levels are higher in people after musical practice. Dr. Alessandro Minutillo, in the Department of Neurosciences and Mental Health in Italy, recruited 48 healthy volunteers, all matched for age and sex. To qualify as a musician for the study, participants had to hold a musical degree in voice or instrument and have been practicing at least three hours a week for a minimum of five years. Plasma BDNF levels were measured in both groups participating in the study.
BDNF is released from neurons in response to neural activity. When a neuron in a circuit is activated, it spews BDNF into the extracellular space. In doing so, it reinforces its own activity. Alone, BDNF is nothing. But paired with the right receptor, the complex cellular events eventually culminating in structural, functional, and cognitive brain changes are initiated.
BDNF acts through receptors in the tyrosine kinase family, mainly TrĸB (pronounced “track B”). The cells that BDNF affects depends on the cells expressing TrĸB. Neurons expressing TrĸB respond by remodeling or stabilizing the synapse (the connection between two neurons), which invites the possibility of new connections and the strengthening of existing ones.
Oligodendrocytes—the myelin-producing cells of the brain—respond by maturing along their lineage to generate more myelin. More myelin wraps along the length of the nerve fiber and alters the speed signals travel, fine-tuning network synchrony. More oligodendrocyte support also means neurons can maintain a higher level of activity. Myelin remodeling via BDNF may underlie some of the white matter changes observed in the corpus callosum and the inferior frontal and superior temporal white matter tracts.
Music is powerful. It changes us in the short term. It changes us over time. No matter what age you are, I hope you don’t hesitate to pick up an instrument and try to learn it. Good or bad, the world could benefit from more sound decoration.