Evolution of music

The emotional origins of music

I have just been sent an alert to tell me that the new ‘Musicae Scientiae’ journal is a Special Issue – Music and Evolution Special Issue 2009-2010 (ISSN 1029-8649), edited by the European Society for the Cognitive Sciences of Music (ESCOM). http://musicweb.hmt-hannover.de/escom

I am looking forward to getting my copy and diving into all the newest theories on the origins of music! In the meantime, and while brushing up on the literature in this area, I came across a nice little summary article by Laurel Trainor. In it Laurel summarises theories for an emotional ‘trigger’ being important in the evolution of music – specifically, that the emotions induced by music are commonly felt by members of a social group, and this shared experience and understanding leads to social cohesion that is necessary for successful group cooperation. For more detailed comment on this theory I recommend David Huron’s book to anyone and everyone! (http://www.amazon.co.uk/Sweet-Anticipation-Psychology-Expectation-Bradford/dp/0262582783)

The present article first outlines the major difficulties in supporting evolutionary theories – namely, the lack of direct evidence and the issue of causality – before going on to discuss 3 links between music and emotion/social bonding that can be seen in modern human behaviour but which may have very ancient source.

1) Emotional reactions to music are similar to other reactions to music.

In my lecture on the similarities between music and language I have a few slides where I compare the features of ‘happy speech’ and ‘happy music’, as well as one or two other primary emotions (i.e. those represented in the Ekman faces (http://en.wikipedia.org/wiki/Paul_Ekman)). In comparing music and language in this way you can see lots of similarities in the way we use sound to convey emotions: Slow, low-pitched and small variations in sound for sadness; fast, high-pitched and rapidly changing sounds for happiness. A simplification, no doubt, but the analogy does seem to stand up to scientific investigation. Laurel points out that these similarities in music and language may exist because musical emotions are triggered by the response of general emotional mechanisms. These general mechanisms, which respond to simple structure in sound, evolved very early on in our history – probably before we were able to communicate emotion with words.

2) Musical expectation is a powerful emotional mechanism

Leonard Meyer’s seminal work in the field of music and emotion in the 50s and 60s brought to fresh light the strength of the link between our musical expectations and our emotional reactions to that music. This is a point that is wonderfully presented in David Huron’s book, with the additional benefit of decades of evidence from neuroscience and behavioural investigations. The main finding from such studies is that highly emotional points in music are typically associated with low-probability events. A similar thing occurs in nature, when unexpected events can cause profound emotional reactions such as shock, awe and joy. In music therefore, when we come across an unexpected tone or transition that affects us emotionally, we might be experiencing the effects of an ancient brain mechanism designed to react to low-probability effects in our environment.

3) Movement is key to social experience

Finally, Laurel presents evidence that music’s role as a powerful social stimulus relies on the way it can trigger individuals to move in coordinated rhythms and tempos. The connection between music and entrainment of natural rhythm is a strong one, even in human infants. Therefore music may be important in social ritual and ceremony because it coordinates individuals (literally!) allowing them to experience synchrony and harmony in both the auditory and motor systems.

Music is a key element of all human societies, and its presence in our most profound and meaningful ceremonies and gatherings (e.g. weddings, funerals, rallies, sporting events) has lead scientists to investigate the reasons why it appears to be such a universal stimulus for functioning human society.

The present article highlights theories of how our social bonding rituals, over thousands of years, have likely been facilitated by the synchrony in our cognitions and behaviours that is triggered by music.

Article: ‘The emotional origina of music’ by Laurel Trainor (2010). Physics of Life Reviews, 7, 44-45.