Toward a model for joint synchronization to musical rhythm

Proc Natl Acad Sci USA 2014 Aug 11. pii: 201324142
Synchronization in human musical rhythms and mutually interacting complex systems

Hennig H
Department of Physics, Harvard University, Cambridge, MA 02138, USA holgerh@nld.ds.mpg.de

Though the music produced by an ensemble is influenced by multiple factors, including musical genre, musician skill, and individual interpretation, rhythmic synchronization is at the foundation of musical interaction. Here, we study the statistical nature of the mutual interaction between two humans synchronizing rhythms. We find that the interbeat intervals of both laypeople and professional musicians exhibit scale-free (power law) cross-correlations. Surprisingly, the next beat to be played by one person is dependent on the entire history of the other person’s interbeat intervals on timescales up to several minutes. To understand this finding, we propose a general stochastic model for mutually interacting complex systems, which suggests a physiologically motivated explanation for the occurrence of scale-free cross-correlations. We show that the observed long-term memory phenomenon in rhythmic synchronization can be imitated by fractal coupling of separately recorded or synthesized audio tracks and thus applied in electronic music. Though this study provides an understanding of fundamental characteristics of timing and synchronization at the interbrain level, the mutually interacting complex systems model may also be applied to study the dynamics of other complex systems where scale-free cross-correlations have been observed, including econophysics, physiological time series, and collective behavior of animal flocks.

Cross-domain cognition and the effect of musical expertise

Front Psychol 2014 Jul 28;5:789
Musicians are more consistent: gestural cross-modal mappings of pitch, loudness and tempo in real-time

Küssner MB, Tidhar D, Prior HM, Leech-Wilkinson D
Department of Music, King’s College London, London, UK

Cross-modal mappings of auditory stimuli reveal valuable insights into how humans make sense of sound and music. Whereas researchers have investigated cross-modal mappings of sound features varied in isolation within paradigms such as speeded classification and forced-choice matching tasks, investigations of representations of concurrently varied sound features (e.g., pitch, loudness and tempo) with overt gestures-accounting for the intrinsic link between movement and sound-are scant. To explore the role of bodily gestures in cross-modal mappings of auditory stimuli we asked 64 musically trained and untrained participants to represent pure tones-continually sounding and concurrently varied in pitch, loudness and tempo-with gestures while the sound stimuli were played. We hypothesized musical training to lead to more consistent mappings between pitch and height, loudness and distance/height, and tempo and speed of hand movement and muscular energy. Our results corroborate previously reported pitch vs. height (higher pitch leading to higher elevation in space) and tempo vs. speed (increasing tempo leading to increasing speed of hand movement) associations, but also reveal novel findings pertaining to musical training which influenced consistency of pitch mappings, annulling a commonly observed bias for convex (i.e., rising-falling) pitch contours. Moreover, we reveal effects of interactions between musical parameters on cross-modal mappings (e.g., pitch and loudness on speed of hand movement), highlighting the importance of studying auditory stimuli concurrently varied in different musical parameters. Results are discussed in light of cross-modal cognition, with particular emphasis on studies within (embodied) music cognition. Implications for theoretical refinements and potential clinical applications are provided.

Creative Classroom: The ticks ‘come marching in’ in singing professor’s microbiology class (YALE NEWS)

An example of joint action here at Yale!

“I like to sing, whether anybody sings along or not,” says the Yale microbiologist. “But I especially like having the students join in. There’s something about singing together that is ancient and wonderful and magical. It builds community.

Read the story here.

Research Question: Groove!

As a performing musician with interests in a wide variety of genres, I have always been interested in comparing my musical tastes with that of my friends. I often wonder why I enjoy folk music so much, but cannot for the life of me get into heavy metal music, something that a friend values so highly. Or, why I am compelled to move my body along to the music in that catchy electro-pop song but strongly prefer to stay absolutely still when watching a performance of my favourite Beethoven symphony. These interests have led me to the topic of “groove.”

There is relatively little research on the topic of groove, and many big questions merit our attention, in hopes of a greater understanding of the complex phenomenon that is listening to music, and specifically in learning more about our response to music as engaged listeners.

In 2006, Guy Madison set out to learn more about groove, and operationally defined it as “wanting to move some part of the body in relation to some aspect of the sound pattern.” He went on to explain that we can now only be certain that groove does indeed exist, but we cannot yet confirm that it is brought forth by the characteristics of sound patterns, and that this experience of groove is consistent among listeners. Other questions are related to cultural and social upbringing, and if these factors greatly influence the experience of groove and musical taste. Experiments have been attempted (playing brief audio clips of various genres) to try to better understand groove, and Madison claims that groove is no more difficult to detect than other dimensions found for music experience in music research.

In my own experience, it seems as though the concept of groove is a highly personal and somewhat esoteric concept. Many musical moments that I find to carry a certain groove have not been viewed in the same light by my peers. As this course is obviously focused on aspects of rhythm, it is also a great interest of mine to learn more about the rhythmical characteristics of groove , specifically if there is a certain “something” that must be present for groove to exist. In addition, I am quite curious to discover the understanding and identification of groove among highly-trained musicians. Is groove something that can exist in any genre of music?

To aid in my research, my hope is to select a small number of musical excerpts (varying in musical style) and isolate brief sections that I deem to have groove. I would then like to show these selections to my musician networks (from a diverse pool of classical musicians, band members, rappers and so forth) and determine if there are consistencies in the experience of groove, and why this is so.

I believe this to be an engaging topic, as it is still quite fresh in terms of scholarly research, and hope that it will be a fascinating period of discovery!

 

Embodiment, Rhythm and Cognition

 

 I want to begin to better approach the understanding between the kinesthetic embodiment of rhythm through the means of cognition, specifically memory.  Many tasks of experimenting with metric entrainment involve some sort of tapping, usually hand rather than foot for data-recording purposes. This phenomenon, linked to my understanding of the learning West African dance-drumming, made me question this method of learning rhythms and how our bodies react to hearing them, especially from a Western cultural background.

Part of Vijay Iyer’s work discusses some of these same tropes that I am interested in pursuing. He draws links between the claim that perhaps music is meant to be moved to with the Anlo-Ewe culture of Ghana, West Africa.

What I want to address is the fact that sometimes in West African dance-drumming (the fact that the meaning of the word in Ewe is interchangeable between dance and the music only strengthens this argument of the different cultural approach of movement pertaining to music), one starts to move in order to recall the drum language, or rhythms that dictate those movements. In designing an experiment, would subjects be able to better remember rhythms depending on whether they learned movements alongside those same rhythms?

It is unusual in Western culture to learn rhythms based on movement, but what if we used a set of movements to help remember a rhythm, or even lyrics? We learn dance from melodies or in a counting manner (or learn concepts set to music), and I want to explore the other direction of that correlation; using movement to help trigger rhythmic recall. Subjects (without certain experience, dance, etc) would be given certain patterns to learn, accompanied by movements or alone- just the movements too- and then try to reproduce those rhythms, being allowed to move along with their attempts or not. Does this movement have to be synchronized with the beats, or dance at all? Do certain parts of the body elicit better ability of memorization? Would this method work best with polyrhythms, and only serve to confuse subjects struggling to learn movements along with a simple pattern?

Dalcroze eurhythmics is an example of possible applications of addressing these questions. While it does not answer any of them specifically, this method of teaching music to students using embodiment underlines the importance of kinesthetic movement reinforcing neural circuits involving memory, and gives us only more reason to want to fully understand its effectiveness. 

 

Research Question: Groove!

As a performing musician with interests in a wide variety of genres, I have always been interested in comparing my musical tastes with that of my friends. I often wonder why I enjoy folk music so much, but cannot for the life of me get into heavy metal music, something that a friend values so highly. Or, why I am compelled to move my body along to the music in that catchy electro-pop song but strongly prefer to stay absolutely still when watching a performance of my favourite Beethoven symphony. These interests have led me to the topic of “groove.”

There is relatively little research on the topic of groove, and many big questions merit our attention, in hopes of a greater understanding of the complex phenomenon that is listening to music, and specifically in learning more about our response to music as engaged listeners.

In 2006, Guy Madison set out to learn more about groove, and operationally defined it as “wanting to move some part of the body in relation to some aspect of the sound pattern.” He went on to explain that we can now only be certain that groove does indeed exist, but we cannot yet confirm that it is brought forth by the characteristics of sound patterns, and that this experience of groove is consistent among listeners. Other questions are related to cultural and social upbringing, and if these factors greatly influence the experience of groove and musical taste. Experiments have been attempted (playing brief audio clips of various genres) to try to better understand groove, and Madison claims that groove is no more difficult to detect than other dimensions found for music experience in music research.

In my own experience, it seems as though the concept of groove is a highly personal and somewhat esoteric concept. Many musical moments that I find to carry a certain groove have not been viewed in the same light by my peers. As this course is obviously focused on aspects of rhythm, it is also a great interest of mine to learn more about the rhythmical characteristics of groove , specifically if there is a certain “something” that must be present for groove to exist. In addition, I am quite curious to discover the understanding and identification of groove among highly-trained musicians. Is groove something that can exist in any genre of music?

To aid in this research my hope is to select a small number of musical excerpts (varying in musical style) and isolate brief sections that I deem to have groove. I would then like to show these selections to my musician networks (from a diverse pool of classical musicians, band members, rappers and so forth) and determine if there are consistencies in the experience of groove, and why this is so.

I believe this to be an engaging topic, as it is still quite fresh in terms of scholarly research, and hope that it will be a fascinating period of discovery!

 

Individual Research Question

As shown by studies we have examined in class, our memories are limited. This limitation of our memories results in many of the occurrences that happen when listening to music. I would like to examine how efficient our memory is at remembering and restating rhythms of different familiarities, complexities, and presentations. My question is to examine to what extent does the complexity and presentation of a rhythm affect how well and quickly one can remember it. Also, an area of interest within this topic is whether there is a significant difference of results between age groups and musical ability levels.

Recent studies have shown that older children tend to learn rhythmic patterns at a much quicker rate than younger children, suggesting variances among rhythmic memories between different age groups. It may be that as certain parts of the brain develop, rhythmic memory is enhanced. This could help us understand which parts of the brain in particular are critical in retaining a rhythm. It has also been shown that musicians tend to be better than non-musicians at recalling a rhythm. This may be due to certain areas of the brain being more highly trained and utilized in musicians than in non-musicians.

Observing how well our memory can hold onto different types of rhythms may provide insight on what our mind prioritizes and how information regarding rhythmic input is organized. It may also show what we can consciously recall based off of the differing rhythmic stimuli. The information obtained from these studies could be used to better understand the mental processes used to hear and recall a rhythm. Effects of this knowledge may be the improvement of music education, since knowing the particular capabilities of certain age groups and musical abilities could enable a curriculum designed to fit those capabilities.

Stories and Music

From the beginning of our species, humans have been telling stories; we’re obsessed with them. From ancient origin myths to movies and television, Greek tragedies to Broadway, and papyrus scrolls to paperback novels, we tell stories in all sorts of ways, and we can’t get enough of them. With them we find meaning, we imagine, and we emote; storytelling is uniquely human, and evokes the very behaviors that are generally thought to define what makes us human.

Often found coupled with storytelling is music. We often use music to tell stories that evoke emotions, or make us think and imagine. The relationship between narrative and music is one that is difficult to parse out, however. You can have stories without music; can you have music without a story? It seems obvious to say yes; music may not have the same characters, the same actions, and the same plot that we recognize so easily in stories, but they have themes. They have recurring tones and sounds, interactions between those themes, and a syntax as complex as that of the languages that form stories without music. Seemingly most important, both music and story are essentially experiences – they unfold in time, and must be experienced. So how do we understand this relationship between music and stories? Is music a specialized type of story, simply part of a much larger concept of stories? Or are they two separate things that interact?

Some questions Patel raises in his book, Music, Language, and the Brain, are how we define and understand the meaning created by music, and whether emotion is inherent in the music, separate entirely, or whether it may exist both within and separate from the music. He enumerates a few different theories about how these concepts may be related, but ultimately leaves this question unanswered. In the aim of understanding these connections better, along with music’s connection to story, I have several questions I wish to explore. For example:

Can a story change the perception of the emotions of a musical piece? Or perhaps vice versa, can a musical piece played after/during a story change emotional perception?

What contributes to perceiving a narrative in a piece of music? Do different rhythms give rise to different narrations? Perhaps by asking subjects to create narratives for many different rhythms will reveal some consistencies or similarities.

How do structures of music relate to structures of stories? Do people recognize and connect the two? Perhaps by finding or creating a story with a similar arc as a piece of music, I can ask people to identify the larger structure, and see which is better, if there are any similarities, and so on.

Are people consistent with the creation of narratives in music? For instance, do people generally create similar sounding narratives for the same piece of music?

Expectation Theory states that we create unconscious expectations when listening to music, and was shown to do so with short groups of tones. Do stories create the same types of expectations? Perhaps using either long or short sentences to create a seeming “rhythm”, and then changing to the other type might create a similar violation of expectation, and make it more difficult to remember the content.

Does music in stories help us remember things better? Perhaps setting a story to music would help subjects remember the content of the story better than those who got the story without the music.

Though there hasn’t been a lot of work done in this area; Patel’s book is a good general overview of research that was current at the time, but rather than give a conclusive answer to questions, Patel gives several possible theories that could answer the question for each. The next step will be to continue to seek out further research that specifically focuses on what I’m interested in, to see if there is any sort of precedence for the types of experiments I want to run.

*These are many questions, and while it is unlikely that I will be able to create an experiment that explores all of them, many of them are related, and so I believe it will be possible for me to create a large scale experiment, or a slew of smaller experiments that will give me data to answer a fair amount of the questions I have.

Caste study: The “swing” ratio

One fairly active area of research on microtiming has been focused on the phenomenon of the jazz “swing”. Here is a small collection of articles on this topic. What are the main research questions tackled by these studies? What are some of the common findings? Are there conflicting experimental results? What might explain these differences?

Write a response to one or more of these prompts in reply to this post by Thursday, October 2, 9:00 AM.

Collier & Collier (2002), “A study of timing in two Louis Armstrong solos”

Friberg & Sundstrom (2002), “Swing ratios and ensemble timing in jazz performance: Evidence for a common rhythmic pattern”

Benadon (2006), “Slicing the beat: Jazz eighth-notes as expressive microrhythm”

Honing & de Haas (2008), “Swing once more: Relating timing and tempo in expert jazz drumming”

Butterfield (2011), “Why do jazz musicians swing their eighth notes”