Two types of anticipation in sensory-motor coupling

The anticipatory timing control in sensory-motor coupling is indispensable to generate coordinative movement among humans, however its cognitive mechanism still remains obscure. In this study we used synchronization tapping task as a model system, and negative asynchrony phenomenon where the tap onset precedes the stimulus onset was analyzed as an example of the anticipation. Especially, applying dual task method, the relationship between the anticipation mechanism and the higher brain function such as attention and working memory was investigated. The results revealed two types of anticipatory timing control. In the inter stimulus-onset interval (ISI) range of 450 to 1800 ms, automatic anticipation that is not affected by attentional resources was observed and was based on feed forward dynamics. In the 2400 to 3600 ms range, the anticipation showed trade-off relationship in the allocation of attentional resources. Magnitude of synchronization error (SE) between tap onset and stimulus onset in this region was scaled by the ISI and the feed back dynamics concerning ISI was suggested. Accordingly, anticipation in timing control was shown to be a dual processing between the attentional process and the embodied automatic process.