Researchers at the University of Barcelona, the Bellvitge Institute for Biomedical Research, the Santa Creu i Sant Pau Hospital Institute for Biomedical Research, the Autonomous University of Barcelona and McGill University (Montreal) have published a study that shows for the first time a causal relationship between the dopamine system and music.
A new study published in the Proceedings of the National Academy of Science (PNAS) reveals a causal relationship between dopamine and reward responses in humans when listening to music. The study was carried out by researchers from the Cognition and Brain Plasticity Research Group at the University of Barcelona and the Bellvitge Biomedical Research Institute (UB-IDIBELL), as well as the former Human Neuropsychopharmacology Research Group and the PK / PD Modeling and Simulation groups coordinated by Dr. Marta Valle del Dra. Marta Valle from the Institut d’Investigació Biomèdica de l’Hospital de la Santa Creu i Sant Pau, the Universitat Autònoma de Barcelona and the Montreal Neurological Institute of McGill University.
The researchers pharmacologically manipulated the transmission of dopamine in twenty-two participants while listening to music, and have shown for the first time the causal relationship between dopamine and the motivation and satisfaction of listening to music. While the precursor of dopamine, levodopa, increased hedonic experience and motivational responses, such as wanting to buy a song, risperidone reduced them. These results open up a new view of the neurobiology and neurochemistry of reward responses associated with music, and contribute to the open debate about understanding the human brain.
Humans regularly participate in comforting activities such as listening to music, singing or playing. Understanding how the brain translates a sequence of sounds such as music into a satisfying experience is challenging.
In this study, researchers asked whether dopamine, a neurotransmitter with an important role in regulating pleasurable experiences and motivating people to act in one way or another, has a direct role in the positive experience music provokes. To answer this question, they pharmacologically manipulated the availability of dopamine to the neuronal receptors of the participants. In three different sessions, one week apart, the experts orally administered a dopamine precursor (levodopa, which increases dopamine availability), its antagonist (risperidone, which reduces dopamine signaling), and a placebo (lactose, as a control). Researchers anticipate that, if dopamine has a causal role in the satisfaction of music, levodopa and risperidone should have opposite effects in terms of musical satisfaction and motivation.
Laura Ferreri, researcher at UB-IDIBELL and first author of the article, explains that “the study clarifies the role of the human dopamine system in terms of abstract rewards. In addition, “these results challenge those of previous studies that have been done on animal models, in which dopaminergic manipulations showed a clear role for dopamine in motivation and learning, but in which its role in regulating hedonic responses with primary prizes such as food remained controversial”. The researcher concludes that these results “indicate that dopaminergic transmission in humans may have different roles from those proposed in affective processing, specifically with respect to abstract cognitive activities, such as listening to music”.
Electrodermal response
The authors indirectly measured changes in the sensation of pleasure and reward by checking the electrodermal activity of the participants, a technique for evaluating emotional changes (in this case, the hedonic impact of music). In each session, participants listened to their favorite songs to more than ten other songs (the authors and groups chosen were Alejandro Sanz, Amaia Montero, Antonio Orozco, Auryn, Birdy, Katy Perry, Maldita Nerea, Melendi, One Direction and Taylor Swift). The purpose was for them to evaluate the experiences subjectively (real-time evaluation and general evaluation of each song). Motivational responses were also measured by asking participants how much they would pay for each song. In order to control the implication of reward processes in a situation without music, the researchers also carried out a task that evaluated monetary reward, in which participants could earn or lose money.
Overall, the results showed that pharmacological interventions modulated the reward responses provoked by music. Risperidone, unlike levodopa, reduced participants’ chills, considered a physical manifestation of the peak of satisfaction when listening to music. As shown with changes in electrodermal activity, participants’ scores on emotional responses were higher with levodopa and lower with risperidone, scores that were also compared with placebo. These results coincide with those obtained when money was used as a reward, since, in response to a higher prize, enthusiasm was increased with levodopa and reduced with risperidone. Finally, participants were more open to spending money on levodopa than on risperidone: they were more motivated to listen to more music when dopamine transmission was improved than when it was blocked.
Antoni Rodríguez Fornells, ICREA researcher and head of the UB-IDIBELL group, explains that this study “shows for the first time the causal role of dopamine in musical satisfaction and motivation: enjoying music, taking pleasure, wanting to listen to a song again, and wanted to buy it …, all this depends on the dopamine we release.
Article reference:
Ferreri, L.; Mas-Herrero, E.; Zatorre, R.; Ripollés, P.; Gómez-Andrés, A.; Alicart, E.; Olivé, G.; Marco-Pallarés, J.; Antonijoan, R. M.; Valle, M.; Riba, J., i Rodríguez-Fornells, A. «Dopamine modulates the reward experiences elicited by music», Proceedings of the National Academy of Science, 2019.
