Monday, December 15, 2008

Does rhythm make our bodies move?*

Why do some people dance more rhythmically to music than others? Are these differences genetically or culturally determined? These are some typical questions journalists who are interested in rhythm research like to ask.

The link between musical rhythm and movement has been a fascination for a small yet passionate group of researchers. Early examples, from the 1920s, are the works by Alexander Truslit and Gustav Becking. More recently researchers like Neil Todd (University of Manchester, England) [1] defend a view that makes a direct link between musical rhythm and movement. Direct in the sense that it is argued that rhythm perception can be explained in terms of our physiology and body metrics (from the functioning of our vestibular system to leg length and body size).

While this might be a natural line of thought for most people, the consequences of such theories are peculiar. They predict, for instance, that body length will have an effect on our rhythm perception, longer people preferring slower musical tempi (or rates), shorter people preferring faster ones. Hence, females (since they are on average shorter than men) should have a preference for faster tempi as compared to males.

To me that is too direct and na├»ve a relation. There are quite a few studies that looked for these direct physiological relations (like heart rate, spontaneous tapping rate, walking speed, etc.) and how these might influence or even determine rhythm perception. However, none of these succeeded in finding a convincing correlation, let alone a causal relation. In addition, they ignore the influence that culture and cognition apparently have on rhythm perception. Nevertheless it should be added that embodied explanations do form a healthy alternative to the often too restricted ‘mentalist’ or cognitive approach.

An intriguing study in that respect was done by Jessica Phillips-Silver and Laurel Trainor (McMaster University, Canada) [2] a few years ago. They did an inventive experiment with seven month old babies, and showed that body movement (i.e. not body size) can influence rhythm perception. They had a group of mothers bounce their infants on a rhythm that could be interpreted as either being in duple or in triple meter. They could show (using a head-turn preference procedure, measuring the time an infant pays attention to a stimulus) that bouncing in three or in four influenced the perception of the infant. While one could be critical on some important details, this is a striking empirical finding, and a small step forward in trying to underpin the relation between rhythm cognition and human movement.

ResearchBlogging.orgJ. Phillips-Silver (2005). Feeling the Beat: Movement Influences Infant Rhythm Perception Science, 308 (5727), 1430-1430 DOI: 10.1126/science.1110922

* Repeated blog entry from July 17, 2007.

1 comment:

  1. Rhythmic ability based on body length is of course absurd. However, proportion and center of gravity might have some effect. My daughter is pretty tall for almost 4 - she's coordinated but slow in comparison to kids her age. Her more "compact" friends are much faster and were more physical at an earlier age.

    I did some work this summer in the area of vocology (vocal science). One area that continues to confound researchers and practitioners alike is vibrato. Certainly the intrinsic properties of the vocal folds, larynx, and vocal tract will affect the flexibility of the voice. But what about cyclical patterns and "interference" from the heartbeat, for instance. Makes me wonder if body rhythms are "off" in people who lack rhythm?