Georgia State University ScholarWorks @ Georgia State University Music Faculty Publications School of Music 2014 How jazz musicians improvise: The central role of auditory and motor patterns Martin Norgaard Georgia State University, [email protected] Follow this and additional works at: https://scholarworks.gsu.edu/music_facpub Part of the Music Commons Recommended Citation Norgaard, M. (2014). How jazz musicians improvise: The central role of auditory and motor patterns. Music Perception. 31(3), 271-287. DOI: 10.1525/mp.2014.31.3.271. This Article is brought to you for free and open access by the School of Music at ScholarWorks @ Georgia State University. It has been accepted for inclusion in Music Faculty Publications by an authorized administrator of ScholarWorks @ Georgia State University. For more information, please contact [email protected]. Auditory and Motor Patterns 271 HOW JAZZ MUSICIANS IMPROVISE:THE CENTRAL ROLE OF AUDITORY AND MOTOR PATTERNS MARTIN NORGAARD defenders from the opposing team, the actual wording Georgia State University of a presenter using an outline, or the notes of a musical improvisation. All these behaviors are created in real IT IS WELL KNOWN THAT JAZZ IMPROVISATIONS time in which revision is not an option. Should errors include repeated rhythmic and melodic patterns. What occur they must be incorporated into upcoming output is less understood is how those patterns come to be. One as they cannot be undone. All these behaviors are theory posits that entire motor patterns are stored in guided by rules. The basketball player must execute procedural memory and inserted into an ongoing moves that are physically possible and that are allowed improvisation. An alternative view is that improvisers within the rules of the game, the presenter will follow use procedures based on the rules of tonal jazz to create the outline using words and phrases guided by gram- an improvised output. This output may contain patterns matical rules, and the improviser will use notes that fit but these patterns are accidental and not stored in pro- within the given musical context. cedural memory for later use. The current study used It is well known that only expert practitioners are a novel computer-based technique to analyze a large indeed able to create this output seamlessly. A beginner corpus of 48 improvised solos by the jazz great Charlie basketball player will drop the ball just like the novice Parker. To be able to compare melodic patterns inde- presenter will stumble over words and lose his train of pendent of absolute pitch, all pitches were converted to thought. Through training, execution becomes more directional intervals listed in half steps. Results showed fluid and errors subside. A large part of this learning that 82.6% of the notes played begin a 4-interval pattern process is mastering the motor movements themselves and 57.6% begin interval and rhythm patterns. The (e.g., Schmidt & Lee, 2011) but the behaviors described mean number of times the 4-interval pattern on each above add another level of complexity. How are discrete note position is repeated in the solos analyzed was 26.3 movements combined to create a novel output that and patterns up to 49-intervals in length were identified. uniquely fits a given situation? In the case of musical The sheer ubiquity of patterns and the pairing of pitch improvisation the problem can be stated as follows: Per- and rhythm patterns support the theory that pre- formance of both composed and improvised music formed structures are inserted during improvisation. involves learned movements. However, during musical The patterns may be encoded both during deliberate improvisation the exact configuration of those move- practice and through an incidental learning processes. ments is determined in the moment. How is this accom- These results align well with related processes in both plished? What information is stored in the brain that language acquisition and motor learning. enables this complex behavior? One theory posits that memorized motor patterns form the basis for the impro- Received: October 22, 2012, accepted May 15, 2013. vised output (Pressing, 1988). A competing theory emphasizes learned rule-based procedures (Johnson- Key words: improvisation, corpus research, pattern, Laird, 2002). The current study explores this question Charlie Parker, computer-assisted musical analysis by analyzing a large corpus of improvisations by jazz great Charlie Parker. It is well documented that jazz improvisations contain T HAS RECENTLY BEEN SUGGESTED THAT THE repeated melodic figures often referred to as patterns study of creativity needs to be divided into various (Berliner, 1994; Finkelman, 1997; Owens, 1974). One I areas according to the cognitive processes involved explanation is that the artist simply inserts pre-learned (Dietrich & Kanso, 2010). One such area is the study of structures (Pressing, 1988). Pressing divided improvisa- novel output created in real time under certain con- tions into collections of note groupings that he labeled straints. Examples of such behavior would be the novel ‘‘events.’’ Each event is triggered by a creative intention movements of an expert basketball player bypassing in the form of a mental schema that contains a cognitive Music Perception, VOLUME 31, ISSUE 3, PP. 271–287, ISSN 0730-7829, ELECTRONIC ISSN 1533-8312. © 2014 BY THE REGENTS OF THE UNIVERSITY OF CALIFORNIA ALL RIGHTS RESERVED. PLEASE DIRECT ALL REQUESTS FOR PERMISSION TO PHOTOCOPY OR REPRODUCE ARTICLE CONTENT THROUGH THE UNIVERSITY OF CALIFORNIA PRESS’S RIGHTS AND PERMISSIONS WEBSITE, HTTP://WWW.UCPRESSJOURNALS.COM/REPRINTINFO.ASP.DOI:10.1525/MP.2014.31.3.271 272 Martin Norgaard image of sound and corresponding motor realization. chromatic passing tones. Though the improvisers’ As the mental schema is executed, the improviser com- descriptions of their own thinking may be different pares the intention with the actual performed output from the actual cognitive processes used, it is extraor- through various feedback loops. Subsequent events dinary how well these two strategies align with the two often share features with preceding events, resulting in competing theories mentioned above. a related set of note groupings. The improviser may also One recent study investigated whether learned pat- choose to interrupt the flow by initiating an event that is terns or procedures guided the improvisational choices completely unrelated to the preceding event. of jazz musicians (Goldman, 2012, 2013). Advanced An alternate explanation is that the patterns simply jazz pianists were asked to improvise on a common jazz appear by chance as the improviser uses learned pro- chord progression (rhythm changes) with either the cedures that follow the rules of tonal jazz (Johnson- right or left hand and in both a familiar key (B-flat) and Laird, 2002). Johnson-Laird argues two main con- an unfamiliar key (B). Dependent variables included the straints are enough to determine the pitches of the use of non-diatonic notes and entropy as a measure of improvised output in tonal jazz. The first is the under- melodic predictability. Participants used more diatonic lying chord progression and procedures related to the notes and less variation in the unfamiliar key. Goldman use of scales, chord tones, and passing tones. The sec- interpreted these findings in relation to the generative ond is contour considerations. The selected pitches are strategies employed. Forced to improvise in an unfamil- inserted into prototypical jazz rhythms. Crucially, the iar key, ‘‘improvisers used their explicit knowledge of entire process does not require storage of intermediate chord tones and scales to improvise’’ (Goldman, 2012, results explaining how subconscious procedures may p. 367) as stored motor programs were not available. control the improvisational output without the use of Indeed, the improvisers described accessing auditory working memory. According to this explanation images of appropriate patterns that they were not able ‘‘instead of a list of fragments of rhythms, motifs, and to execute in an unfamiliar key. Therefore, it appears so on, the algorithms described make use of rules.’’ that familiarity with keys may influence whether pat- (Johnson-Laird, 2002, p. 440). Acknowledging that terns or procedures are the dominant improvisational improvised solos often contain motifs that are devel- strategy. oped later in the solo, Johnson-Laird argues that To more closely examine how improvisational mate- extemporized salient phrases may be stored in long- rial is created, I first review relevant research on motor term memory and then used later in the same solo. behavior and how movements can become integrated However, according to Johnson-Laird, the improviser with an auditory image. I then describe research that does not develop a memorized library of melodic fig- addresses the function of patterns in language learning. ures that is accessed during all improvisations. Finally, the current research paradigm is outlined and Norgaard (2011) suggests that both processes occur at linked to previous analysis of improvisational corpora. different times. This qualitative investigation was based on participants’ comments concerning their thinking RELATED MOTOR RESEARCH during an improvisation. Immediately following an Pressing’s (1988) theory fits well with the idea of a gen- improvised performance, participants were interviewed eralized motor program (GMP) as a central memory as they were listening to a recording