The Mind on Music
By Patti North
Anyone who has ever had an “ear worm—that maddening musical refrain the brain occasionally seizes upon and won’t let go of—may wonder why we don’t get an equivalent experience with other sensory input. We don’t talk about having an “eye worm,” repeatedly visualizing a fragment of an image for hours or even days later. Could it be that music is hard-wired into our brains in a way that no other sensory memory can match?
Researchers at Georgetown are studying how and why music is so neurologically dominant. The answer seems to lie in rhythm and how the brain processes sequences—and they are confident that a better understanding of these functions will lead to more effective medical treatment and disease prevention.
Although use of music and use of language are both complex brain activities, scientists are nearly certain that music preceded language in human development.
“We know from studying humanoid fossils and from comparing our brains with those of nonhuman primates that the brain structures that allow us to modulate our voices, or sing, are older than the brain structures we need to articulate and form vowels and consonants,” says Georgetown auditory neuroscientist Josef Rauschecker, PhD, DSc, director of the Laboratory for Integrative Neuroscience and Cognition.
Music also has direct access to the brain’s limbic system and thus to our emotions. This means that music has long had an observable healing effect on the brain, restoring some of its plasticity— but the effects could not be well quantified until fairly recently. Brain imaging has moved the study of music from psychology into the realm of neuroscience. “Using functional MRI, we can now see how the brain works in both afflicted and healthy subjects,” Rauschecker explains.
Anticipating growth in the field of restoration of function, Rauschecker hopes to see more young people with music backgrounds drawn to neuroscience. “We need to bring together the clinicians, musicians, brain imagers, and neurologists and have them talk to each other and see the patients together. A vision like this is developing here at Georgetown that we hope to fully animate.”
Stroke victims with aphasia, for example, may not be able to speak, but are suddenly able to sing the lyrics of a song, perceive rhythm, and tap along. “The sensorimotor link between the auditory and the musical quality in the motor systems is clearly there —it’s not lost even in people with dementia,” Rauschecker said.
The benefits could also accrue to healthy people. As the population ages, and memory drops off—beginning at about age 60— music could help us understand how to better access and read out the memory chains we already possess and have stored away, by strengthening some of the connections or synapses between nerve cells.
“There are places in the world where the music doesn’t emphasize melody, and the concept of harmony doesn’t exist at all, but rhythm—the integration of audition, motor, vestibular, and vision—is universal across cultures,” says Jessica Phillips-Silver, PhD, a postdoctoral fellow in the Georgetown Laboratory of Integrative Neuroscience and Cognition at the School of Medicine who studies rhythm entrainment, or how rhythm integrates body and brain. “We hear the melody, but we feel the beat.” For example, newborn infants respond demonstrably to being rhythmically bounced or patted by their parents.
Phillips-Silver also points to rhythm outside the realm of what we think of as music. “Comedians and actors strive for good timing,” she notes, “which significantly impacts the quality of the performance.”
It’s not surprising then, that our relationship with rhythm is often traced to the beating of our mother’s heart in utero—but other animals also experience this without developing music.
“We want to understand how music resides in the brain and the body,” Phillips-Silver says. “When we fully understand that, we will get to a new frontier of the effect of music in medicine. We want to capture a process that is at the core of what it means to be human.”