The rhythmic brain.

Music is a universal but still poorly understood form of human communication in which abstract patterns of sound can cause people to cry, laugh, dance, reflect, bond and even mate. Rhythm is a basic organising principle of music, providing a strict temporal framework for an infinite variety of playful and expressive musical behaviours, from clapping and dancing in a group to a virtuosic violin solo. This temporal organisation exists on a number of hierarchical levels (the pulse, the bar, the phrase), allowing for the simplest forms of synchronisation and prediction as well as highly complex, large-scale musical structures. Considering its primacy in musical behaviour, rhythm has not yet received the scientific attention it deserves. Perhaps due to the rich harmonic complexity of our Western tonal system, the focus of much music psychology and music neuroscience research has tended towards the hierarchical structures of pitch, melody, tonality and harmony. However, if we consider the diversity of musical languages across society, across cultures and across history, rhythm soon comes to the forefront as a ubiquitous component of human behaviour. Many cultures emphasize rhythm, with melody playing a less significant role. In addition, many music therapists and educators emphasize the role of rhythm in their work. In June 2006, an interdisciplinary conference on the topic of Rhythm, Time and Temporal Organisation was held at the University of Edinburgh as the inaugural conference of the Institute for Music in Human and Social Development (IMHSD) (http://www.music.ed.ac.uk/Research/imhsd/Rhythm2006/ programme.html). The conference brought together neuroscientists, therapists, philosophers, musicologists, musicians, psychologists, sociologists, educators and dancers to consider the nature of rhythm and timing from evolutionary,