There are two comically extreme positions on how music (or really any stimulus) affects observers. At one end, the position that all of our experiences are equivalent, dictated by the common signal, at the other, individual subjectivities make our impressions and reactions irreconcilable. In studying how people respond to music, it’s obvious that the reality lies somewhere in the middle: parts of our experience can match that of others, though differences and conflicts persist. I’ve spent years developing this thing called activity analysis to explore and grade the distance between absolute agreement and complete disarray in the responses measured across people sharing a common experience.

As people attend to a time varying stimulus (like music) their experience develops moment by moment, changes prompted by events in the action observed. What we have, in activity analysis, is a means of exploring and statistically assessing how strongly the shared music coordinates these changes in response. So if we are tracking smiles in an audience during a concert, we can evaluate the probability that those smiles are prompted by specific moments in the performance, and from there have some expectation of how another audience may respond.

If everyone agreed with each other, this would not be necessary, and if nothing was common between listeners’ experience, this would not be possible. Instead empirical data appears to wander in between, and with that variation comes the opportunity to study factors nudging inter-response agreement one way or the other. We’ve seen extreme coherence, that of the crowd singing together at the top of their lungs in a stadium saturated with amplified sound, and polite but disoriented disengagement is a common response to someone else’s favourite music. We need to test the many theories on why so many different response (and distributions of responses) arise from shared experiences, and Activity Analysis can help with that. Finally.

Here is hoping I can get back to sharing examples of what this approach to collections of continuous responses makes possible. The data and analyses have been waited too long already.