Can people tap concurrent bimanual rhythms independently?

If people could tap 2 rhythms independently, 1 rhythm with each hand, training people to tap the rhythms separately should enable them to tap the rhythms concurrently. However, nonmusician participants in the present experiments were unable to produce accurate intervals when lapping bimanually after they had mastered the rhythms individually. That finding implies that tapping concurrent rhythms requires an integrated sensory-motor representation incorporating the actions of both hands into a single pattern. Although training the rhythms separately cannot specify an integrated code, such specification is possible with bimanual training. Bimanual training quickly led to accurate tapping, but most participants then did not tap correctly either of the separate rhythms that had been mastered in the context of concurrent tapping. That finding suggests that the integrated representation does not code either rhythm independently.