Following the initial SR assessment, participants were assigned a personal rhythm. Half of these were faster than 2Hz (3Hz), whilst others were slower (1Hz). Then, in groups of four, participants tapped their rhythms together to form a polyrhythm, whilst attempting to keep time as well as possible. There were always two people with fast rhythms and two with slow rhythms in a group, but only in half of the groups were the personal rhythms ever the same (shared rhythm groups).

Group tapping setup diagram (above), and picture (below): The diagram shows the setup used in the group tapping stage. TP='Tapping Pad' and P='Participant'. Speakers played polyrhythms to familiarise participants with the task. Two participants always tapped fast rhythms, (e.g. P1 and P2), whilst the others tapped slow rhythms. In 'same rhythm' groups, these pairs would tap exactly the same rhythm.

Our expectation was that when in a shared rhythm group, participants’ SRs (when measured again after the group tapping) would be significantly altered in the appropriate speed direction. Participants who played a fast rhythm AND were in a shared rhythm group (where another member played the same rhythm), showed this effect, with SRs speeding up significantly (for this group, average SR before = 2.5Hz, whilst average SR after = 3.6Hz) . Unfortunately, the slow rhythm people didn’t seem to experience this effect (average SR before = 2.1Hz, average SR after =  2.6Hz). I postulated that this was perhaps due to 1Hz being too slow to resonate with people in the same way, with participants instead ‘filling in’ beats in their head, so that they were effectively becoming entrained to a faster rhythm. This would explain the slight (though non-significant) increase in SR. To summarise, when tapping together in groups only one condition stood out as having enough of an effect on people to alter their spontaneous rate, and that was playing a rhythm faster than their original SR when another person was also playing that exact same rhythm. There were also some slight, non-significant changes in the ‘different rhythm’ groups, as can be seen below (if only that 3rd bar went down as far as the first one goes up…!):

Changes in SR: This graph shows the amount of change (Hz) in SR from before to after the group tapping stage. Fast= participants played rhythms with a 3Hz speed, Slow= participants played at 1 Hz. Same= Same rhythm group, Different= Different rhythm group.

So what? Well, one of my main theoretical angles was the importance of music to society, culture and ultimately evolution. Moving together in time, and the ability to synchronise with others may have been crucial to early communication and the fulfilment of societal goals. Synchronising with one another forms bonds (by changing our internal pacing to match that of a partner), and consequently allows us to work together more effectively. This is the reason soldiers march along in time with one another. Synchronisation is crucial to survival, and we’ve got a multitude of ‘mirror neurons‘ to show for it. We feel more comfortable when mirroring the body movements of those we are talking to, and the crucial systems involved in this aid our offspring in integrating their actions with the world staring them in the face and blowing raspberries.

This was a small study, so I don’t want to generalise with the results too much, but they suggest promising things; moving in synchrony with another appears to impact our natural rhythms, we adjust some fundamental element of our inner self to match the social world around us. This could be suggest an instant tendency to adjust our ‘body clocks’ in a similar way to women who synchronise their menstrual cycles. Who knows, I just think its promising. Its a shame we didn’t get the same result with the slower rhythms, but I’m fairly confident that refining the paradigm (or even just an increase in sample size – probably both) would yield positive results here. I may go further with this stuff at some point, I feel like there’s something in it. I’m pretty sure Martine will pursue it to some extent in the future also, so keep an eye on her if you’re interested.

Anyway, I digress. I think I’ll bring this to a musical conclusion. I’d like to note that such an effect could go on to explain some of the immense physiological and psychological pleasure we experience when interacting musically together – the ultimate group synchronisation exercise. If out hypothesis is correct, synchronisation leads to bonding, and we all know that bonding leads to one of our favourite things… No not that! Just general, good old fashioned pleasure. Music provides a platform for us to bond on a level that transcends all the bullshit modern life throws at us. So grab your instruments, or pots and pans, give those vocal muscles a stretch, or just get on your feet and dance together, because we can play around with synchronisation at no extra cost, and its damn good fun.

This post details information from a small part of my undergraduate dissertation. Certain measures and variables have not been mentioned here as I wanted to talk specifically about the findings related to Spontaneous Rate changes. I will be making the entire dissertation available here shortly.

I would like to thank the organisers of RPPW12 for including my work in their programme (allbeit under the wrong name!), and Martine Turgeon for supervising my dissertation.