UofM Researchers Challenge the Relationship Between Musical Training and the Brain's Speech Processing Function

December 11, 2018 - Dr. Gavin Bidelman and Kelsey Mankel of the University of Memphis have published new findings in the Proceedings of the National Academy of Sciences (PNAS) that challenge assumptions about the impact of musical training on the human brain.

In contrast to commonly held beliefs, the study shows that formal music experience is unnecessary to enhance the brain's speech function. Instead, it appears some people are endowed with highly adept auditory systems which offer similar speech-language benefits as taking years of music lessons. This may be welcome news for those who are challenged when it comes to music.

For decades, musicianship has been widely reported to enhance auditory brain processing related to speech-language function. The study breaks new ground by assessing the relative roles of "nature vs. nurture" in this equation. In other words, does formal training in musicianship create true experience-dependent changes in the brain—called plasticity—as often assumed, or are there innate, pre-existing differences in auditory system function that play a role?

To answer this question, the study used EEG to measure brain responses to speech in young, normal-hearing listeners with no musical training. Using the Profile of Music Perception Skills (PROMS), subjects were divided into high and low musicality groups based on their innate perceptual skills. The results showed that individuals who are naturally better in music perception tasks, but possess no formal music training ("musical sleepers"), have superior neural encoding of clear and noise-degraded speech, mirroring enhancements reported in trained musicians. This provides clear evidence that certain individuals have musician-like auditory neurobiological function and tempers assumptions that music-related neuroplasticity is solely experience-driven. Importantly, the study also reveals that formal music experience is neither necessary nor sufficient to enhance the brain's neural encoding and perception of speech.

Further comparisons between "musical sleepers" and actual trained musicians did, however, show additional enhancements in experienced musicians. So, while nature gets you some of the way there, it seems nurture provides an additional boost towards achieving those "golden ears."

"This research is an exciting opportunity to rethink how we engage musicianship in discourse around brain development and neurorehabilitation," says Bidelman. "Our findings show some individuals have naturally better, musician-like faculties in how their nervous system captures speech information. At the same time, it's clear that musicians enjoy additional benefits. So, a natural chicken-and-egg question emerges: whether "musical sleepers" are more likely to pursue music in the first place. We need to consider both nature and nurture when we talk about the potential brain benefits of musical training."

This work was supported by a grant from the University of Memphis Research Investment Fund (UMRIF) and by NIH/NIDCD R01DC016267. Bidelman is an associate professor in the Institute for Intelligent Systems and School of Communication Sciences and Disorders, where he directs the Auditory Cognitive Neuroscience Laboratory (memphis.edu/acnl). Mankel is a doctoral student in Communication Sciences and Disorders at the UofM.

For more information on this project or to learn more about Bidelman's research, contact research@memphis.edu.