The brain source of creativity

Where does creativity come from and can we see the sources of creative thought in the brain? If we could answer these questions then there would be important implications that go well beyond musical performance.

Creativity is an areas that we can find quite hard to teach on the Music, Mind and Brain masters, compared to other more well trodden areas of research. In comparison to, for example, studies of music and language or musical emotion there is hardly any research on the creative processes behind musical composition and performance.

Creativity is one of those ephemeral concepts that can be quite hard to capture, like mental imagery. I always thought that getting the creative process into a scanner might be a fun task to try but then getting instrumentalists to play in a scanner is fraught with problems. Singing of course, is possible. And who is best at spontaneous lyrical improvisation? Rappers of course!

A new study out in Nature has reported a fascinating experiment where 12 freestyle rap artists (5-18 years of professional experience) were asked to rap memorized lyrics on an 8-bar instrumental track (conventional condition) or to perform lyrics that were improvised spontaneously, on the same instrumental track (improvised condition). Both these conditions took place in an fMRI scanner and the authors reported a pattern of unique activations that were associated with improvisation but which that they argue could provide a signature for creativity in general.  

For those who are interested in the methods, the authors utilized spatial independent component analysis (sICA) methods recently developed in their laboratory to effectively remove imaging artifacts associated with connected speech or song, making it possible to study improvised rap using fMRI for the first time.

Consistent with a previous study of melodic improvisation the authors reported ‘a dissociated pattern of activity within the prefrontal cortex: increases in activity throughout the MPFC, extending from the frontal pole to the border of the pre-SMA (more pronounced in the left hemisphere), and simultaneous decreases in the DLPFC, from its orbital to superior regions’ (more pronounced in the right hemisphere).

It should be noted that although the left hemisphere activations would be expected in a linguistic task, the activations noted here were associated uniquely with the improvised and not the conventional condition so can not be ascribed to normal language processing per se, rather unique aspects of the improvisation task.

The authors state that “This pattern – activation of medial and deactivation of dorsolateral cortices – may provide a context in which self-generated action is freed from the conventional constraints of supervisory attention and executive control, facilitating the generation of novel ideas.”

In addition, enhanced activity observed in the caudate may support rapid online sequencing of ongoing behaviors in the improvised as opposed to the conventional condition.

The authors then carried out a connectivity analysis to work out how the patterns of activation and deactivation that they observed in the brain may be related to each other. The connectivity results revealed strong positive correlations between activity in a primary seed region in the MPFC and inferior frontal and cortical premotor areas.

These regions were themselves positively correlated with activity in amygdala which itself was strongly coupled to an extended network that included the right IFG, and IPL and anterior insula in both left and right hemispheres. “The connectivity analyses therefore suggested the emergence of a more widespread, large-scale network that might play a role in lyrical improvisation”.

Overall, the results reveal an extensive network that the authors argue is implicated in the initial stages of lyrical improvisation, rooted in prefrontal (in particular areas involved in executive control) and premotor areas but also extending into motivational and emotional areas. Interestingly the authors suggest that “…as a whole, this entire network is more effectively coupled during spontaneous creative behaviour – perhaps facilitating what has been described as a psychological ‘flow’ state“.

Article: Siyuan Liu, Ho Ming Chow, Yisheng Xu, Michael G. Erkkinen, Katherine E. Swett, Michael W. Eagle, Daniel A. Rizik-Baer & Allen R. Braun (2012) Neural Correlates of Lyrical Improvisation: An fMRI Study of Freestyle Rap. Nature Scientific Reports