Age moderates association between set shifting and complex rhythm performance in healthy adults

Musical rhythm performance has previously been associated with cognitive functioning in healthy older adults. However, the extent to which performance of increasingly complicated rhythms associates with cognitive functioning is less well known. We hypothesized that older adults would perform worse than younger adults, and that executive functions and processing speed would associate with rhythm performance. Forty-nine neuropsychiatrically healthy participants were included in analyses (n = 25, ages 18-35; n = 24, ages 55-89). Neuropsychological assessment included measures of processing speed, working memory, set shifting and nonverbal reasoning. Participants learned and performed 30 musical rhythm exercises of increasing complexity. There was a significant main effect of rhythm complexity on timing error. Age also showed a significant main effect, with older adults exhibiting greater error overall. Set-shifting ability was identified as a factor in timing error in older adults. These findings suggest that older adults are less accurate than younger in performing rhythms and that performance in older adults is sensitive to baseline executive functioning. Further research on underlying differences in brain structure, metabolism and function related to rhythm performance is necessary to understand mechanisms of change in rhythm abilities and relationship with non-musical cognitive processes.