The contributions of biological maturity and experience to fine motor development in adolescence

Fine motor function develops into adulthood, but little is known about the differential effects of biological maturation and experience on speed and complex sequential performance of the hand. The objective of the study was to disentangle the differential effects of biological maturation, chronological age, and specific motor experience on fine motor skills of the hand during adolescence. To determine maturity levels, ultrasonic bone age (BA) was assessed in 225 adolescents (123 females; BA mean 13.4 ± 1.5 years, range: 9.9 to 17.9 years). The role of experience was evaluated based on chronological age (CA, mean 13.5 ± 1.2 years, range: 11.1 to 16.5 years), musical instrumental experience, and handedness. When specific musical instrumental experience is not present, biological maturation level is a significant predictor of complex fine motor performance, while chronological age predicts simple repetitive motor performance. When present, the amount of highly specific musical instrumental experience becomes the main predictor of sequential performance.