Emerging Behavioral Flexibility in Loop Writing: A longitudinal study in 7- to 9-Year-Old Primary School Children

The development of the ability to adapt one's motor performance to the constraints of a movement task was examined in a longitudinal study involving 7 to-9-year-old children who were asked to perform a preparatory handwriting task. The capacity for sensorimotor synchronization was captured by the standard deviation of the relative phase between pacing signals and writing movements and the capacity to adjust wrist-finger coordination while performing repetitive movements was analyzed by autocorrelations of the vertical pen-tip displacements. While the capacity for synchronization improved with age, the autocorrelations were positive at short time lags only and hardly changed with age. A measure of "the long-term memory" of time series (Hurst exponent) confirmed that the findings were systematic rather than noise. Collectively, the results indicate that flexible movement strategies emerge early on in the first 3 years of formal handwriting education. Implications for educational and clinical practice are considered.