This study aimed to clarify the age-specific characteristics of bimanual coordination in young adults, young old adults, and old old adults.
The participants were 97 healthy young adults and 324 healthy older adults, all of whom performed bimanual coordination tasks. These tasks included an in-phase task, where participants tapped their thumb and index fingers simultaneously on both hands as quickly as possible, and an anti-phase task, where the tapping was performed alternately between the two hands. Each task was performed for 15 seconds with eyes closed. The features of bimanual coordination during each task (total movement distance, mean and standard deviation of the peak distances, slope of the approximate line for the peak distances, number of taps, mean and standard deviation of intervals, and tapping frequency) were measured. A three-way mixed-design analysis of variance (ANOVA) with hand × task × group factors was used for statistical analysis to compare each feature. The significance level was set at 5%.
Based on age, the participants were classified into the groups: 97 young adults, 102 young old adults, and 222 old old adults. Statistical analysis showed no significant interaction effect between hand × task × group factors for any of the measured items (p > 0.05). However, a significant interaction was found for the number of taps, mean tap interval, and tap frequency in the task × group factors, where bimanual coordination performance significantly decreased in the anti-phase task compared to the in-phase task, in young old adults compared to young adults, and in old old adults compared to young old adults (p 0.05).
Interhemispheric interactions via the corpus callosum play an important role in bimanual coordination. It has been reported that the structural and functional connectivity of the corpus callosum declines with age, declining bimanual coordination performance. Based on these findings, this study suggests that age-related reduction of interhemispheric inhibition may have impaired bimanual coordination in young old adults more than in young adults, and old old adults more than in young old adults.
These results suggest that the number of taps, mean tap interval, and tap frequency may have potential as a tool for assessing age-related changes in bimanual coordination.
age-related change
number of taps