Age-related declines in visuospatial working memory correlate with deficits in explicit motor sequence learning

Numerous studies have shown that older adults exhibit deficits in motor sequence learning, but the mechanisms underlying this effect remain unclear. Our recent work has shown that visuospatial working-memory capacity predicts the rate of motor sequence learning and the length of motor chunks formed during explicit sequence learning in young adults. In the current study, we evaluate whether age-related deficits in working memory explain the reduced rate of motor sequence learning in older adults. We found that older adults exhibited a correlation between visuospatial working-memory capacity and motor sequence chunk length, as we observed previously in young adults. In addition, older adults exhibited an overall reduction in both working-memory capacity and motor chunk length compared with that of young adults. However, individual variations in visuospatial working-memory capacity did not correlate with the rate of learning in older adults. These results indicate that working memory declines with age at least partially explain age-related differences in explicit motor sequence learning.