Wong, P. M., Skoe, E., Russo, N., Dees, T., & Kraus, N. (2007). Musical experience shapes human brainstem encoding of linguistic pitch patterns. Nature Neuroscience, 10(4), 420-422. doi:10.1038/nn1872
Chapter 10 has a primary focus on auditory processes in both language and music. It discusses the structures of the ear and the auditory cortex, as well as the neural activity in discerning properties of sound, such as loudness, location, and patterns. One property of sound the authors of our text discuss is pitch, the frequency of sounds waves, which is begun to be coded by hair cells in the cochlea of the ear. Auditory signals such as music and speech have been attributed to the cortical region of the brain. However, this particular research article examines the subcortical regions that are involved in audition. Specifically, researchers recorded the activity in the brainstem during the encoding process of linguistic pitch. To do this, they measured frequency following response, which is assumed to begin in the auditory brainstem, or the inferior colliculus to be exact. The development and learning of language is not entirely innate or biological. In fact, previous research has shown that experiences within a language enhance how we encode linguistic information. For example, Chinese language speakers can easily distinguish between short syllables that sound exactly the same to western listeners, and these sounds actually convey different meanings within their own language. Based on this knowledge, researchers decided to present three syllables with different intonation and measure the frequency following response. With these measures, investigators compared musicians with individuals who were not musicians. As expected, there was a positive linear relationship between musical training and the tracking of a pitch. The results were consistent with their hypothesis; musicians had more robust and faithful encoding in the brainstem than non-musicians. This basically meant that musical ability predicted the ability to perceive the differing sound structures in a foreign language. The interesting implication of this research is that it could provide a neurological explanation for previous research findings that musicians have a stronger ability to learn language. Musicians obviously have more experience in encoding, deciphering, and responding to information regarding pitch from their frequent musical experiences. The interaction between auditory acuity and cognitive demands is suggested by the researchers to be mediated by feedback from the higher cortex areas to the inferior colliculus. This means that information regarding pitch is relayed from subcortical strucutres to the outer cortex, which leads to more successful interpretation of linguistic pitch. The researchers in this study, though, advise caution with interpretation, since correlational relationships could be explained by a third variable, such as genetics.
This is an interesting article. That music and second languages are processed in the right hemisphere may suggest an underlying function.
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