Page 35 - WINTER2019

occur at specific beats within a given meter; we also expect certain pitch intervals and harmonies to follow others. The systematic fulfillment and violations of expectations have long been posited to contribute to emotional content and perceived meaning in music (Meyer, 1956). For example, although beat and meter establish rhythmic expectations, syncopation is a violation of expectations that can lead to an even richer music listening experience. This balance between predictability and prediction violations is critical to the enjoy- ment of music. Through prolonged exposure, humans acquire knowledge of and predictions for musical features that are common in our culture.
Although our emotional responses to music can be complex, multidimensional, and context dependent, recent insights show that linking music to the reward system of the brain can be fruitful in revealing why humans appreciate music. Although music is a relatively abstract interplay of sound pat- terns, it can trigger the release of dopamine, a neurochemical that is released during the experience of rewards such as food, sex, and recreational drugs (Ferreri et al., 2019). Listening to music that we value activates the striatum, a dopamine-rich set of brain regions, and the striatum is correlated in activ- ity with the auditory cortex (Salimpoor et al., 2013). This functional coupling between the auditory cortex and reward- sensitive regions is an especially compelling account of why humans love music. In effect, music might be considered an auditory channel toward areas of the brain that are sensitive to reward.
Further support for this view comes from the finding that white matter connectivity between the auditory cortex and the emotion and social processing regions of the brain are larger among people who experience “chills” when listening to intensely pleasurable music (Sachs et al., 2016). In con- trast, people who are insensitive to the pleasures of music, in a condition known as musical anhedonia, have diminished physiological and neural sensitivity to the rewards of music listening, despite normal reward responses to nonmusical reward tasks such as gambling (Martinez-Molina et al., 2016). Although individuals differ in reward sensitivity to music, acquired musical anhedonia is very rare, even among people with focal brain damage (Belfi et al., 2017). This means that in the vast majority of people recovering from neurological and/or psychiatric disorders such as depression or demen- tia, music could be used in therapeutic interventions due to its reliable engagement of the reward system, which, in turn, guides motivated behavior.
Conclusions
The value of the studies reviewed above comes not only from satisfying the intellectual curiosity of how music works and why we have music but also in the hopes that a deeper under- standing of the tools and principles of music will enable the design of better musical interventions for a variety of appli- cations, from recovery from neurological and/or psychiatric disorders to enhancing the optimal function of the healthy developing brain.
References
Albouy, P., Mattout, J., Bouet, R., Maby, E., Sanchez, G., Aguera, P. E., Daligault, S., Delpuech, C., Bertrand, O., Caclin, A., and Tillmann, B. (2013). Impaired pitch perception and memory in congenital amusia: The deficit starts in the auditory cortex. Brain 136(5), 1639-1661.
Ayotte, J., Peretz, I., and Hyde, K. (2002). Congenital amusia: A group study of adults afflicted with a music-specific disorder. Brain 125(2), 238-251. Belfi, A. M., Evans, E., Heskje, J., Bruss, J., and Tranel, D. (2017). Musical
anhedonia after focal brain damage. Neuropsychologia 97, 29-37. Bendor, D., and Wang, X. (2005). The neuronal representation of pitch in
primate auditory cortex. Nature 436(7054), 1161-1165.
Caclin, A., Brattico, E., Tervaniemi, M., Naatanen, R., Morlet, D., Giard, M. H., and McAdams, S. (2006). Separate neural processing of timbre dimen- sions in auditory sensory memory. Journal of Cognitive Neuroscience 18(12),
1959-1972.
Cirelli, L. K., Einarson, K. M., and Trainor, L. J. (2014). Interpersonal syn-
chrony increases prosocial behavior in infants. Developmental Science
17(6), 1003-1011.
Deutsch, D., Dooley, K., Henthorn, T., and Head, B. (2009). Absolute pitch
among students in an American music conservatory: Association with tone language fluency. The Journal of the Acoustical Society of America 125(4), 2398-2403.
Dohn, A., Garza-Villarreal, E. A., Heaton, P., and Vuust, P. (2012). Do musicians with perfect pitch have more autism traits than musicians without perfect pitch? An empirical study. PLoS ONE 7(5), e37961.
Ferreri, L., Mas-Herrero, E., Zatorre, R. J., Ripollés, P., Gomez-Andres, A., Alicart, H., Olivé, G., Marco-Pallarés, J., Antonijoan, R. M., Valle, M., and Riba, J. (2019). Dopamine modulates the reward experiences elicited by music. Proceedings of the National Academy of Sciences of the United States
of America 116(9), 3793-3798.
Flinker, A., Doyle, W. K., Mehta, A. D., Devinsky, O., and Poeppel, D. (2019).
Spectrotemporal modulation provides a unifying framework for auditory
cortical asymmetries. Nature Human Behaviour 3(4), 393-405.
Grahn, J. A., and Brett, M. (2007). Rhythm and beat perception in motor
areas of the brain. Journal of Cognitive Neuroscience 19(5), 893-906. Grahn, J. A., and Brett, M. (2009). Impairment of beat-based rhythm dis-
crimination in Parkinson's disease. Cortex 45(1), 54-61.
Griffiths, T. D., Kumar, S., Warren, J. D., Stewart, L., Stephan, K. E., and Friston, K. J. (2007). Approaches to the cortical analysis of auditory
objects. Hearing Research 229(1-2), 46-53.
Hyde, K. L., Lerch, J. P., Zatorre, R. J., Griffiths, T. D., Evans, A. C., and
Peretz, I. (2007). Cortical thickness in congenital amusia: When less is
better than more. Journal of Neuroscience 27(47), 13028-13032.
Janata, P., Birk, J. L., Van Horn, J. D., Leman, M., Tillmann, B., and Bharu-
cha, J. J. (2002). The cortical topography of tonal structures underlying Western music. Science 298(5601), 2167-2170.
Winter 2019 | Acoustics Today | 35