Beyond reach and grasp: the development of high-order planning for manual actions in typically developing children

High-order action planning is the capacity to anticipate and organise two or more action steps before moving, requiring integration of cognitive, motor, and perceptual processes. High-order planning underpins goal-directed behaviour, enabling efficient problem-solving, skilled tool use, and adaptation to the environment. Developmental research shows that high-order planning skills emerge gradually in childhood, with adult-like responses appearing in older childhood, depending on the task. This systematic review investigates the development of high-order action planning in manual tasks from infancy to adolescence. Following the PRISMA 2020 guidelines, we searched PubMed and Scopus and identified 37 relevant studies after screening. Behavioural and kinematic differences during movement indicate that children as young as three years exhibit adult-like performance in high-order planning in tasks with low motor requirements and show degrees of adaptation in tasks that detect graded adjustments. Non-adult-like performance in young children appears more attributable to motor constraints than to a lack of planning ability. Children show high interindividual variance and occasionally non-linear development until around eight years. Recent research has begun to disentangle the development of action planning from the development of cognition. Findings show that high-order action planning is more closely associated with motor-related skills than with high-level, abstract planning and cognition. We argue that future research should focus on inter-individual variance and adopt real-time, multimodal measures to reveal mechanisms underlying high-order action planning.