Music is an integral part of human cultures around the world. Common wisdom suggests that listening to music has an affect on mental states, for better or for worse. Rock and roll music can pump you up, while soothing classical piano can mellow you out. However, are these effects real? What is really happening in the body when you listen to say, a track of relaxing music? Is it any different from simply listening to pleasant sounds or resting quietly? Scientists in a collaborative team in the US, Germany, and Switzerland ventured to find out.
Previous studies on the effects of music on the body usually only tested the music on very small groups of people, which can lead to bias. Many also failed to measure actual biochemical markers of stress, making it difficult to determine if changes in the body are actually occurring. In this study, the researchers tested various types of sounds on 60 healthy people, all female, between the ages of 20 and 30 and then measured actual biochemical stress indicators from the women’s saliva. The researchers explained that, because the stress response differs by sex, they wanted to confine their group to only one sex in order to avoid variation in results from drowning out any real changes in stress levels. It is worth noting that applicants who had clinical depression, tinnitus, or music training, as well as those who drank alcohol and smoked regularly, were not accepted as study participants.
Prior to the experiment, the participants were given standardized tests that measure depression, anxiety, and emotionality. They were also given a survey to determine their music preferences, and it is worth noting that preference for classical music was high in this group. These measures were taken to ensure that depression and music preferences did not play a role in how relaxed the women became as a result of the study. For example, an anxious person might have a more difficult time becoming relaxed despite any intervention, and a person who hates classical music may not feel relaxed while listening to it.
Now, onto the experiment. The participants were divided randomly into three groups. One group listened to Miserere by Gregorio Allegri. The second group listened to a recording of flowing water. The third group rested quietly with no music. Each group’s session lasted for ten minutes. Saliva was sampled from each participant before and after the intervention to establish a baseline. This would be used later to measure various stress markers. Then, the participants were put into a stressful situation — a mock job interview. This particular scenario was chosen because it is a common stressful experience, and thus, stress could be induced ethically. After the stress test, a third saliva measurement was taken. The participants also filled out a set of questionnaires reporting how stressed they felt after the mock interview.
This begs the question — how do we measure “stress” anyway? Simply asking a person if they are stressed can lead to bias since stress is different for everyone. It is also a very general term describing many different experiences. Researchers decided to accompany the self-reported stress levels of the participants with actual biochemical and physical measurements – cortisol levels, salivary amylase, heart rate, and respiratory rate.
Cortisol is a hormone that is commonly elevated when a person is stressed. Salivary amylase is an enzyme produced by the digestive system, but it is also an indicator of the “fight or flight” response and another sign of stress. These chemicals are secreted in the saliva, making measurement convenient. Elevated heart rate and changes in what is called the “Respiratory sinus arrhythmia” or the syncing up of heart rate with breathing, can also change in response to stressful situations.
As it turns out, listening to relaxing music before a stressful event actually increased cortisol levels! This surprised the researchers. On the contrary, listening to relaxing music did seem to help the participants recover from this heightened “fight or flight” mode more effectively after the stressful event was over. Self reported anxiety, depression, and emotionality were not affected significantly by any of the interventions.
Despite doing their best to control for confounding factors and using objective stress measurements, they do mention that because the study was done on such a narrow demographic (young, female, healthy) that it may not be applicable to the general population. More research in this area would be needed, possibly on different groups of people with different preferences, genders, and health statuses.
Nevertheless, the study was well designed and produced provocative results that corroborate past research on music and stress. The major conclusion here is that the effect of music on human psychology is a highly individual experience and affects a symphony, pun intended, of hormones, enzymes, and cognitive processes that require many studies to fully understand.