It can be rock, opera, classical music or jazz, but it has always been assumed that every individual likes some kind of music. This universal belief has been dismantled by a team led by psychologist Josep Marco at the University of Barcelona, in a study recently published in the journal Current Biology. No matter what the melody sounds like, for some people music just does not mean anything.
The study had a prior phase in which researchers, together with colleagues from the University of Montreal, asked about the differences in musical tastes. In other words, with their study, published in the journal Music Perception last year, they just wanted to find out how music is enjoyed at the individual level. “We were taking it for granted that everyone loves music, and suddenly the following question arose – what if it’s not true?” Marco says.
In their previous work, they observed that there were 5% of participants, to whom a reward system was applied to measure their reactions to different types of music, who scored low, and the next study sought to clarify whether this small percentage, “a not-negligible percentage,” were directly insensitive to what is considered a universal pleasure.
“In the scientific literature there were three reported cases of people who, after suffering a stroke, had lost their taste for music, and it was also known that it was something that happened to individuals with depression, but what we were trying to find out was whether it could happen to healthy people who did not also have perception problems,” said the study’s lead author.
To find this out, the researchers selected three groups of ten people each of whom, in the previuos work, had shown high, medium or low sensitivity to musical rewards, which was assessed by a questionnaire –also developed by the same authors– the Barcelona Musical Reward Questionnaire (BMRQ). Participants in all three groups had a similar sensitivity to the overall rewards (e.g. monetary) and were able to correctly perceive music.
Then the selected subjects were subjected to two experiments. First, they had to describe their degree of pleasure when listening to certain music and, second, quickly answer a series of questions in order to earn or not earn real money (token amounts).
To objectively measure their emotional response, the psychologists recorded, in addition to the responses, the rhythm of the heartbeat and the electrodermal activity “very sensitive to emotions.” “What was seen is that in the monetary area all had the same response, while in the musical group that we had defined as low sensitivity, no reaction was seen, compared with the other two groups that did have it,” says Marco.
What is especially clear in the study is that people who exhibit this musical insensitivity suffer no disorder. They are perfectly healthy people “that can get pleasure from other sources.” Anecdotally, Marco recalls that when people from the low sensitivity group (of which not all turned out to be totally insensitive) were asked to select a tune themselves to submit to the test, many were unable to do it and had to rely on family or friends to choose just one song.
Months after the publication of the study, Marco says that his lab began receiving e-mails from people who hitherto had felt like weirdos. “Some said that all their lives they had been accused of being depressed, when it wasn’t true,” he adds.
Researchers continue to work in this area. Now, they are using functional magnetic resonance imaging, although they have not yet completed the sample. Their theory is that although the sound processing areas are the same in all individuals, it may be that there are differences in the areas associated with more primary rewards. However, we will have to wait for the results before we know for sure.
For now, the work of Marco and his collaborators could have an immediate impact on music therapy, which is used to treat various disorders. “If one is thinking of applying a therapy based on music, one has to be aware that there are people who are not going to be sensitive,” the psychologist from the Catalan university points out.
With regard to the percentage of the population that could be affected by this “non-disorder,” Marco said that in his study it amounted to 5%, but after taking into account possible biases, such as problems of depression which were not specifically discussed in the published work, the percentage could drop to 2-3%. This is a large enough number to disqualify musical insensitivity from being a rare bird.