Developmental changes in prehension during childhood

Area of Science:

• Motor control development
• Childhood developmental milestones
• Human grasping behavior

Background:

• Anticipatory control of grip and load force is not innate.
• This control develops over several years in childhood.

Purpose of the Study:

• To examine the development of grasping behavior in children.
• To quantify the relationship between grip force and object vertical acceleration.

Main Methods:

• Children and adults used a precision grip to lift an instrumented object of varying size and weight.
• Measured grip force, grip force rate, and object's vertical position and acceleration profiles.

Main Results:

• Distinct developmental milestones in precision grip maturation observed from 2 to 9 years.
• Negative correlation between peak acceleration and grip force in 2-year-olds (r=-0.51).
• Positive correlation emerged by age 3 (r=0.28) and strengthened up to age 9; anticipatory control strategies began emerging around age 4.

Conclusions:

• Grasping skills show significant developmental progression throughout childhood.
• Anticipatory grip force control emerges gradually, with key milestones between ages 2 and 9.
• Children develop symmetrical acceleration/deceleration control and refined grip force application by age 4.