The classical mean negative asynchrony in sensorimotor synchronization is not universal in humans. A cross-cultural study.

The present study examines to what extent cultural background determines sensorimotor synchronization in humans. The direct comparison of Indian and French students, without particular experience in music or dance, or sport, was motivated by the hypothesis that musical exposure to different musical styles causes a variation in basic synchronization to sound function. At first rate limits of this capacity was sought, using a parametric design increasing the sound periodic frequency up to synchronization breakdown. No robust effect was found in that respect. However, another unpredicted change of the so-called negative mean asynchrony was found. Negative mean asynchrony is defined as the anticipation of movement with respect to sound, of about 40ms. The negative mean asynchrony simply disappears in Indians' participants. This result is very intriguing as negative mean asynchrony was considered ubiquitous for decades, and an invariant hallmark of human timing function. Revision of theoretical modelling of sensorimotor synchronization may be required to account to the found variation.