What is different in the brains of people who do not find music to be appealing? A new study published in the PNAS journal attempts to explain the mystery.
In case you’ve ever wondered as to how does the brain of people who are not pleasantly stimulated by music work (a condition known as musical anhedonia), know that we now have an answer: brain mechanisms pertaining to a lack of sensitivity (to music) have been explained by a team of scientists from the Bellvitge Biomedical Research Institute and the University of Barcelona working in collaboration with another group from Montreal’s University of McGill.
Why do the 3-5% of the population who do not experience pleasure in relation to music feel that way? It is to be noted that people falling into this category do not have problems sensing and processing musical information.
“Anhedonic people do not have problems correctly perceiving and processing the information contained in a melody (such as intervals or rhythms) and present a normal pleasure response to other pleasant stimuli (such as money), but do not enjoy musical stimuli”, says lead author of the study, Noelia Martínez-Molina.
The researchers have addressed this issue by focusing on the association between two specific regions of the brain: the auditory and emotional areas. Their work includes findings that could explain our relationship to music in terms of evolution. They started off by making use of functional magnetic resonance imaging (fMRI) to examine the response to music of a group of 45 healthy participants. The latter were to listen to classic songs during the fMRI, and they had to give scores (pleasure values) of 1 to 4.
The results show that people with musical anhedonia had a decreased pleasant response because of a decrease in the activity of a region of the brain associated with the reward system. This area, called the nucleus accumbens, would, however, be very much active when the participants were exposed to other reinforcers like money obtained through betting, which constituted the control part of the study. The scientists interpret these links based on evolution: the auditory areas of the brain together with cortical and subcortical regions.
“It is interesting to consider the evolutionary importance of the connection between the auditory areas, cortical, and the more primitive system of emotional evaluation, subcortical”, says the researcher. “The link between areas ensures that music is experienced as very rewarding, while stressing its importance at an evolutionary level, even when it does not seem obvious what the biological gain of this cultural production is.”