Actions may speak more melodically than sounds. A new study shows that playing a melody on a musical instrument enhances how those melodies are perceived and remembered, above and beyond just listening to them.
“We wanted to understand how the auditory system encodes and responds to musical events that the motor system has learned, says Caroline Palmer of McGill University, and the senior author on the new paper published in the Journal of Cognitive Neuroscience. “Memory for auditory events that the listener has previously produced may inform us about how auditory-motor integration is accomplished in neural networks.”
Led by Brian Mathias, now at the Leipzig Max Planck Institute for Human Cognitive & Brain Sciences, the researchers asked pianists to learn unfamiliar melodies by performing them or by just listening to them, controlling for the number of times the musicians heard the melody. The researchers then took EEG recordings from the pianists while they were listening to all of the melodies that they had learned. Occasionally, incorrect pitches that were out of key, violating the musical syntax, were substituted into the melodies. The pianists had to indicate whether each melody was altered from or identical to one of the original melodies.
They found that producing the melodies compared to listening increased how well the pianists could identify incorrect pitches. And they also found heightened brain activity in areas associated with cortical motor planning, following altered pitches in melodies previously played compared to those listened to.
Palmer and Mathias spoke with CNS about these results, including the timing of neural activity in the EEG results, why pitch is important, and future directions for the work.
CNS: How did you become personally interested in this research area?
BM: As a lifelong learner of the complex skill of music performance, I became fascinated by how performance experience can change the way that the brain listens to music.
CP: When I was a student musician, I wondered how I and my fellow piano performance majors could memorize a musical work in a few days. How did my fingers remember the pattern of movements? How did my memory for finger movements tie to my memory of how the music was supposed to sound?
CNS: Why does pitch perception matter? Why study it?
CP: Memory for pitch involves so many dimensions of sound: frequency, amplitude, duration, and harmonic spectrum — the same dimensions that affect our ability to understand speech, recognize a familiar voice or animal, or environmental sound. It is important to understand how the brain responds to sound produced by our motor system, as it may be that neural networks are privileged for self-produced sound.
CNS: What have we known previously about the role of motor experience in auditory memory and learning?
BM: Previous studies have investigated how individuals generate expectations for upcoming pitches in melodic sequences by exposing listeners to unexpected pitches, such as an incorrect tone in the melody “Happy Birthday”. Before we conducted this study, it was unknown whether motor experience could impact the processing of these unexpected pitches.
CNS: What were you most excited to find? Were any findings surprising?
BM: We were surprised that the unexpected (altered) pitches in melodies that the pianists had learned by performing them elicited enhanced neural responses compared to melodies learned by just listening. This was surprising given that the altered pitches used in this study were quite violating both in terms of their sensory properties (they created dissonance) and musical tonal characteristics (they were “out-of-key”).
We also found that the multiple properties of the altered pitches — dissonance, sensorimotor associations, and tonal characteristics — were processed along different time-courses: The processing of sensory dissonance was associated with a brain wave that occurred about 100 ms following the pitch onset; the processing of sensorimotor associations was associated with a different brain wave that occurred about 200 ms following the pitch onset; and the processing of tonal characteristics was associated with a third brain wave that occurred about 300 ms following the pitch onset.
CNS: What is the significance of your findings for people learning to play a musical instrument?
BM and CP: Experience performing a musical instrument, as well as experience learning to perform specific melodies, can enhance how we remember and recognize those melodies during subsequent perception.
CNS: What do you most want people to understand about this work?
BM and CP: People’s recognition of musical melodies not only takes into account prior tonal knowledge and sensory properties of the acoustic stimulus; it also takes into account prior motor experience performing specific melodies for individuals who can produce those melodies on a musical instrument.
CNS: What’s next for this work?
BM: During future postdoctoral work, I will investigate motoric influences on the learning of foreign language words with Katharina von Kriegstein of the Leipzig Max Planck Institute for Human Cognitive & Brain Sciences.
CP: We plan to investigate further the auditory-motor networks of musicians as they perform with other musicians in ensembles while we record EEG. We are interested in how those networks combine sensory responses to one’s own performance with sensory inputs from other ensemble musicians.
-Lisa M.P. Munoz