The use of online control: a developmental perspective

Area of Science:

• Motor Control
• Developmental Psychology
• Human Movement Science

Background:

• Limited research exists on young children's ability to adapt movements based on changing visual information.
• Understanding visual feedback processing during movement is crucial for developmental motor science.

Purpose of the Study:

• To investigate the capacity of 5, 7, and 9-year-old children to adjust rapid aiming movements when visual target information changes mid-execution.
• To explore the underlying control mechanisms (open-loop vs. closed-loop) employed by different age groups during perturbed movements.

Main Methods:

• A perturbation paradigm was used where target size changed after movement onset.
• Participants (n=45, ages 5, 7, 9) performed discrete rapid aiming movements.
• Temporal and kinematic data, including movement time, peak velocity, and corrections, were analyzed.

Main Results:

• All age groups scaled movement time to the final target size.
• Nine-year-olds demonstrated greater accuracy than 5- and 7-year-olds.
• Movement adjustments primarily occurred after peak velocity, indicating online, closed-loop control in response to visual perturbations.

Conclusions:

• Children as young as 5 years can utilize closed-loop control to modify movements in response to altered visual feedback.
• The findings support a dual-control model involving open-loop execution followed by closed-loop adjustments during aiming tasks.
• Motor control strategies adapt with age, with older children showing enhanced accuracy and potentially more refined online adjustments.