Ontimpr5. Scientific investigations of improvisation
Scientific Investigations of improvisation
- ABSTRACT: To investigate the neural substrates that underlie spontaneous musical performance, we examined improvisation in professional jazz pianists using functional MRI. By employing two paradigms that differed widely in musical complexity, we found that improvisation (compared to production of over-learned musical sequences) was consistently characterized by a dissociated pattern of activity in the prefrontal cortex: extensive deactivation of dorsolateral prefrontal and lateral orbital regions with focal activation of the medial prefrontal (frontal polar) cortex. Such a pattern may reflect a combination of psychological processes required for spontaneous improvisation, in which internally motivated, stimulus-independent behaviors unfold in the absence of central processes that typically mediate self-monitoring and conscious volitional control of ongoing performance. Changes in prefrontal activity during improvisation were accompanied by widespread activation of neocortical sensorimotor areas (that mediate the organization and execution of musical performance) as well as deactivation of limbic structures (that regulate motivation and emotional tone). This distributed neural pattern may provide a cognitive context that enables the emergence of spontaneous creative activity.
- ABSTRACT: It is well known that jazz improvisations include repeated rhythmic and melodic patterns. What is less understood is how those patterns come to be. One theory posits that entire motor patterns are stored in procedural memory and inserted into an ongoing improvisation. An alternative view is that improvisers use procedures based on the rules of tonal jazz to create an improvised output. This output may contain patterns but these patterns are accidental and not stored in procedural memory for later use. The current study used a novel computer-based technique to analyze a large corpus of 48 improvised solos by the jazz great Charlie Parker. To be able to compare melodic patterns independent of absolute pitch, all pitches were converted to directional intervals listed in half steps. Results showed that 82.6% of the notes played begin a 4-interval pattern and 57.6% begin interval and rhythm patterns. The mean number of times the 4-interval pattern on each note position is repeated in the solos analyzed was 26.3 and patterns up to 49-intervals in length were identified. The sheer ubiquity of patterns and the pairing of pitch and rhythm patterns support the theory that pre-formed structures are inserted during improvisation. The patterns may be encoded both during deliberate practice and through an incidental learning processes. These results align well with related processes in both language acquisition and motor learning.
- "Scientists funded by the National Institute on Deafness and Other Communication Disorders (NIDCD) have found that whenever jazz musicians are engaged in the highly creative and spontaneous activity known as improvisation a large region of the brain involved in monitoring one’s performance shuts down, while a small region involved in organizing self-initiated thoughts and behaviors is highly activated. The researchers propose that this and several related patterns are likely to be key indicators of a brain that is engaged in highly creative thought. The study is published in the Feb. 27 issue of the journal Public Library of Science (PLoS) One."
- Steve Smoliar comments:
- "Unfortunately, this study reveals more conflicts than insights. This is best illustrated by two additional excerpts from the Net New Publisher account. One is a summary [other excerpt not included here] of the experimental design:
- During the study, six highly trained jazz musicians played the keyboard under two scenarios while in the functional MRI scanner. Functional MRI (fMRI) is an imaging tool that measures the amount of blood traveling to various regions of the brain as a means of assessing the amount of neural activity in those areas.
- [This study] exposes the pitfalls of trying to study something as subtle as the practice of music in a laboratory environment. Scientific investigation can rarely assess any phenomenon that is not normative, and Coltrane's practices were anything but normative. . . . The most interesting hypotheses that would try to link brain activity to improvisational behavior are likely to be the ones that account for the behavior that is least normative.
- More important, however, is that improvisation is a social practice that goes far beyond the relationship between soloist and instrument, which the experimental design tried to capture. Improvisation is driven by the relationships that are taking place across the entire ensemble. One cannot understand Coltrane's behavior without taking into account the other members of his quartet. Any experiment that does not take this social dimension into account can only provide an impoverished body of data. In fairness, however, the idea of designing an experiment that would yield more valid data is so challenging as to be virtually impossible, at least with current equipment."