Performance of retarded adolescents and nonretarded children on the Tower of Hanoi Problem.

Groups of retarded adolescents and nonretarded children, varying in MA were presented with 2-disk and 3-disk Tower of Hanoi puzzles, solutions to which require a certain amount of logical foresight. Nonretarded 8- to 11-year-old children performed at close to ceiling on the 2-disk task but had difficulty with the 3-disk task. Retarded groups with MAs ranging from 8 to 11 years performed no differently than nonretarded 6- and 7-year-old children. They had some difficulty on the 2-disk task, and very few reached criterion on the 3-risk task. They tended to preseverate in their errors and frequently resorted to game-rule viole perform many years below MA expectations on tasks requiring foresight and logic.