Alan Harvey is an Emeritus Professor at The University of Western Australia and an Honorary Senior Research Fellow at the Perron Institute for Neurological and Translational Science. He is a neuroscientist who has had a life-long interest and passion for music. His book “Music, Evolution, and the Harmony of Souls” was published by OUP in 2017 and was reviewed by Mandy Stefanakis for the Music Trust e-zine. Alan is currently a member of Perth Symphonic Chorus and their chamber choir.
Humans have evolved two complementary, yet largely distinct, interactive communication systems – language/speech and music/dance. Language is the primary means by which we communicate thoughts and ideas, share acquired knowledge within and between generations, develop plans and conceive of future possibilities, imagine events that will not be experienced in our own lifetime. But if language has played, and continues to play, such a fundamental role in human cognition, behaviour and culture, why – as many have wondered through the years – does music and its partner dance remain a human universal? What, if any, is the significance of music-related activities to the species?
A number of ideas have been put forward, including the attraction and selection of mates, and the need for affiliative interactions and social communication between care givers and infants, before the very young learn to speak. In addition, and emphasized here, is the role that music plays throughout human life in facilitating social interactions and promoting trust, empathy and cooperativity. As I wrote elsewhere (Harvey, 2020): “In a group context music-related activities, including dance, encourage the formation of bigger social networks, help to define cultural identity, and may represent a ‘safe-haven’ in which individuals can interact and share experiences without revealing their innermost thoughts and fears.” Here, I briefly document the links between these various aspects of human musicality and what is currently known about the hormone oxytocin; its influence on human behaviour, its likely effects on mental and physical well-being, and speculate how this knowledge may be useful in a therapeutic context.
Oxytocin is a small peptide that is produced by cells in a region of the brain called the hypothalamus. Oxytocin is secreted into the circulation and has long been known to play a critical role during and after childbirth. The nerve cells that make this peptide also send nerve fibres (axons) deeper into the brain itself, forming widespread central projections. Studies on numerous animal species have revealed that, within the brain, oxytocin has a range of effects on cell function and plasticity, and the peptide can also modulate transmission within numerous brain circuits, including those linked to the formation and retention of memories. Behaviourally, in animals oxytocin plays a key role in pair bonding and maternal/offspring attachment, and it has an important influence on social recognition and social memory.
In humans, the measurement and interpretation of endogenous oxytocin levels is difficult for a number of reasons; it has a short half-life in the bloodstream, and while analysis of plasma oxytocin concentrations appear to reflect levels in the brain better than measurements in, for example, saliva, we cannot yet determine where in the brain the peptide is having an effect at any given moment. Nonetheless, and generally consistent with animal studies, levels of the peptide in plasma and/or saliva are higher when mothers are interacting and bonding with their children. Overall, plasma oxytocin concentrations vary with age and differ between males and females, young women having the highest and old men the lowest levels, and differences in endogenous levels have been linked to various measures of trust, anxiety and stress.
Many experimental human oxytocin studies involve intranasal delivery of the peptide and subsequent analysis of its impact on neural processing and human behaviour. Most but not all studies describe positive, prosocial effects, including changes in emotional empathy, recognition and interpretation of emotions, enhanced within group co-operation and trust, and a reduction in the perception of stress and anxiety.
Such influences align closely to the impact that music has on human cognition and emotion, an analogy that is significantly strengthened by comparing (i) the distribution of oxytocin networks in our brain with (ii) regions that are active when listening to music that we think is rewarding/pleasant, and (iii) brain regions that show increased activity when subjects perform tasks involving empathy, altruism and cooperation. These comparisons reveal a considerable overlap in processing architecture within our brains, in my view underscoring the close neurological links between oxytocin, music, and cooperative human sociality.
Given the foregoing, it is perhaps surprising that until now relatively few studies have directly examined the impact of music on oxytocin expression, in solo or ensemble settings. Taking note of the caveats about measuring and interpreting oxytocin levels as discussed earlier, there are reports that group drumming or singing raise salivary oxytocin levels, often associated with a decrease in levels of the stress-related hormone cortisol. Plasma oxytocin levels were also increased in a vocal jazz group, but only when the singers were improvising together. A very recent study found that intranasal oxytocin enhanced positive interactions between performers and reduced performance anxiety!
Both group music-making and exogenous oxytocin delivery heighten empathy, trust and social connectedness, and both can reduce anxiety and perceived stress. Communal dance also increases empathy and social bonding, in addition to effects it has on cognitive performance, general fitness and mental well-being. These various music-related behaviours are rewarding and arousing, and music and dance are known to affect other neuromodulators such as dopamine and the endorphins. Yet, to date, I am unaware of any reports on how oxytocin levels are affected by solo or group dance.
Animal research has told us a great deal about the physiological effects of oxytocin on the nervous system. Its documented effects on brain regions that are involved in memory and social learning are especially relevant, given that music education and training affects brain structure and plasticity, and likely has life-long beneficial effects on aspects of cognition and memory processing.
Such comparative research is perhaps even more important when one considers the broader health benefits of music and its ally dance. Recent non-human and human studies point to a surprising range of physiological effects influenced by oxytocin, including beneficial effects of the hormone in reducing atherosclerosis and protecting against cardiovascular disease, improved immune responses, reduction in pro-inflammatory agents, a lowering of blood pressure, and even regulating glucose levels and influencing appetite and food intake. Again, many of these systemic effects are similar to those that have been reported to be elicited by listening to and/or performing music, including a reduction in blood pressure, modified immune and inflammatory responses, reduced anxiety and stress, and a moderating effect on blood glucose levels. From youth through to old age, music and dance-related exercise are GOOD FOR YOU!
Clearly, more research and more controlled trials are needed to clarify the evolutionary and behavioural links between human musicality and oxytocin biology. Perhaps also relevant to human society today is whether a better understanding of the relationship between music therapy and neuromodulators such as oxytocin may yield positive effects when applying these tools together in a clinical context. Admittedly speculative, it is possible that combined protocols may be of benefit in treating, for example, some neurodegenerative diseases and various psychiatric conditions, assist in the control of chronic and post-surgical pain, and perhaps be a useful aid in the management of neurodevelopmental conditions such as autism spectrum disorder. Time will tell.
For those interested, a more detailed review can be accessed on-line in the journal Frontiers in Human Neuroscience. https://doi.org/10.3389/fnhum.2020.00350