Images of the Brain, Improvising

I’ve just returned from speaking at a fascinating conference hosted by the Stanford Institute for Creativity and the Arts (Sica).  This was the fourth annual “Music and the Brain” conference held at Stanford, and this year the theme of the conference was “Spontaneity and Improvisation.”  I gave the closing talk on Saturday afternoon, emphasing the shared connections between group interaction in jazz and in improvisational theater. Jonathan Berger, a composer and a professor of music at Stanford, and one of the two co-directors of Sica, brought together an interdisciplinary group of brain scientists on the one hand, and music and improvisation experts on the other.

The high point, for me, was the talk by Aaron Lee Berkowitz of Harvard, reporting on three studies. The first was his study of instruction manuals, most of them from around 200 years ago, teaching pianists how to improvise.  At that time, improvisational skill was expected of all pianists; performers were expected to be able to improvise a variety of portions of otherwise-scored pieces, such as the “cadenza”. The second was his study of Harvard professor Robert Levin, a well-known musicologist who is an expert on Mozart, and also is an excellent piano improviser in the classical style of Mozart and Beethoven.  (This is the topic of Berkowitz’s doctoral dissertation in ethnomusicology.)

The third was a brain imaging study that Berkowitz did with Danial Ansari, a professor at the University of Western Ontario.*  They compared the brains of trained pianists improvising a five-note melody on a simple five-note keyboard, with the brains of people playing a simple and fixed five-note sequence (either just pressing the same key five times, or playing the five from bottom to top).  They were asked to improvise in two different ways: first, to improvise a melody but with a fixed rhythm; second, to improvise both the melody and the rhythm.  The idea was to isolate those regions of the brain that are active only when improvising, but not when performing a predetermined pattern.

They found that improvisation, compared to patterned performance, resulted in increased activity in three areas of the brain: the dorsal premotor cortex (dPMC), the anterior cingulate (ACC), and the inferior frontal gyrus/ventral premotor cortex (IFG/vPMC).

In an interview, Berkowitz explained it this way: “The dPMC takes information about where the body is in space, makes a motor plan, and sends it to the motor cortex to execute the plan. The fact [that] it’s involved in improvisation is not surprising, since it is a motor activity. The ACC is a part of the brain that appears to be involved in conflict monitoring — when you’re trying to sort out two conflicting possibilities, like when you to read the word BLUE when it’s printed in the color red. It’s involved with decision making, which also makes sense — improvisation is decision making, deciding what to play and how to play it.” The IFG/vPMC region “is known to be involved when people speak and understand language. It’s also active when people hear and understand music. What we’ve shown is that it’s involved when people create music.”

This is fascinating research, and most of us find these brain imaging studies fairly compelling: it seems like a look deep into the heart of how we create.  But in my own closing talk, I pointed out the limitations of this methodology. I described the collaborative and group nature of ensemble improvisation, and gave several examples of how a performance emerges, unpredictably, from many small creative decisions made, from moment to moment, by each individual in the group.  Brain imaging does a great job of helping us to understand those individual creative decisions; but the full explanation of group improvisation also requires a focus on the interactions among the performers, and how these weave together to generate a collective and shared performance.  Ultimately, the complete explanation of group creativity will have to be interdisciplinary, bringing together brain science, musicology, performance studies, and interaction analysis.  I applaud Sica director Jonathan Berger for organizing a conference that furthered this goal!

*“Generation of Novel Motor Sequences: The Neural Correlates of Musical Improvisation,” NeuroImage.