A number of evidences show that musical cultures differ in a number of aspects including cognitive priorities, musical function and relationships between music, movement and dance. From the methodological point of view, it is very difficult to describe the understanding of rhythm structures: tapping methods are limiting, surveys are very subjective and analyses of performances are ambiguous and multivariate. In this study we realize cross-cultural com- parisons between unconstrained movement responses of Brazilian and Argen- tinian acculturated subjects, responding to samba and chacarera music. The analyses were realized by means of methods that track the density of kinematic events in the metrical structure. The results contrast to traditional models of metric structure by revealing an intrinsic diversity, variability and asymmetry of movement responses and metrical models. The results also show morphological characteristics connected to cultural differences.