Memory dynamics: distance between the new task and existing behavioural patterns affects learning and interference in bimanual coordination in humans.

In order to study memory and learning dynamics, we examined the effects of the distance between a bimanual pattern to be learned, a relative phase of either 90 degrees, 135 degrees, or 158 degrees, and pre-existing patterns at 0 degrees and 180 degrees. Learning was assessed through a practice task, memory through a synchronization-continuation task, and interference through a prompting task recalling nearby patterns. Results were that (1) interference induced a smaller decrease in accuracy and in stability for the pattern closest to the pre-existing patterns; (2) the withdrawal of the stimulus in the continuation task led to consistent changes in accuracy; and (3) learning rate was faster when the to-be-learned pattern was either far from or close to extant patterns. The findings are discussed in terms of flexibility and robustness of underlying coordination dynamics, and of neural-field dynamic models.