Visuospatial Working Memory Capacity Predicts the Organization of Acquired Explicit Motor Sequences

Visuospatial working memory capacity predicts the organization of acquired explicit motor sequences. J Neurophysiol 101: 3116-3125, 2009. First published April 8, 2009; doi:10.1152/jn.00006.2009. Studies have suggested that cognitive processes such as working memory and temporal control contribute to motor sequence learning. These processes engage overlapping brain regions with sequence learning, but concrete evidence has been lacking. In this study, we determined whether limits in visuospatial working memory capacity and temporal control abilities affect the temporal organization of explicitly acquired motor sequences. Participants performed an explicit sequence learning task, a visuospatial working memory task, and a continuous tapping timing task. We found that visuospatial working memory capacity, but not the CV from the timing task, correlated with the rate of motor sequence learning and the chunking pattern observed in the learned sequence. These results show that individual differences in short-term visuospatial working memory capacity, but not temporal control, predict the temporal structure of explicitly acquired motor sequences.