Developing control over the execution of scripts: The role of maintained hierarchical goal representations.

The execution of a script often requires detecting and resolving conflict with a goal, particularly in nonroutine situations. To take the example of taking a bus daily to work, if someone's usual bus is delayed and a bus for another destination comes first, the person must inhibit taking it and wait for the usual one. Young children can gradually acquire the ability to control the execution of scripts in such nonroutine situations, but few studies have explored the control process involved. In two experiments, we investigated the role of developments in the maintenance of hierarchical goal representations and in executive functions. We measured the ability to control the execution of scripts using a task in which children helped a doll select items to wear; clothing options were presented in an unexpected order in the nonroutine situations. The younger children (4-year-olds) could not flexibly control their execution of scripts in nonroutine situations, although they could exogenously detect and resolve conflict if they were prompted to maintain a subgoal. The older children (5-year-olds) endogenously controlled script execution based on a main goal, whereas subgoal maintenance led them to rigidly control their performance. In addition, children's inhibition abilities were associated with their control of script execution. These findings indicate that the development of the control process underlying the execution of scripts in nonroutine situations is partially dependent on the ability to maintain hierarchical goal representations.