Temporal Consistency and Movement Effort of Repetitive Reaching During Continuation in Children and Adults.

The ability to match one's movements to an external beat and maintain that rhythm in the absence of the beat suggests sophisticated, well-developed neural control. Children (aged 5-10 years) were compared with adults (aged 18-30 years) during a repetitive reaching task to determine development of this control. Children as young as 5 years exhibited this control. The mean rate of reaching did not differ between groups nor did it differ during the two phases, suggesting an overall ability to internalize and continuously repeat a given pace. Children aged 5-8 years were significantly more variable than children aged 9-10 years and adults, likely attributable to variability in central control processes. We found a possible transition period of temporal control. Children aged 9-10 years begin to exhibit more adult-like levels of variability with respect to temporal consistency and movement effort.