End‐state comfort in two object manipulation tasks: Investigating how the movement context influences planning in children, young adults, and older adults

The movement context (pantomime, pantomime with image/object as guide, and actual use) has been shown to influence end‐state comfort—the propensity to prioritize a comfortable final hand position over an initially comfortable one—across the lifespan. The present study aimed to assess how the movement context (pantomime, using a dowel as the tool, and actual use) influences end‐state comfort when acting with objects (glass/hammer) that differ in use‐dependent experience. Children (ages 6–11, n = 70), young adults (n = 21), and older adults (n = 21) picked up an overturned glass to pour water and a hammer to hit a nail, where the handle faced away from the participant. End‐state comfort was assessed in each movement context. Findings provide support for an increase in end‐state comfort with age, adult‐like patterns at age 10, and no difference between older adults and 8‐ to 9‐year‐old children. In addition, this work revealed that perception of “graspability” led to an increase in end‐state comfort in the hammering task; therefore, suggesting our ability to act with objects and tools in the environment is influenced by use‐dependent experience and object perception. Results add to our understanding of changes in motor planning abilities with age, and factors underlying these changes.