Teaching motor responses to a child with trisomy 18: A preliminary study

Kusano et al. (2022) worked with one toddler who has trisomy 18. The child had very low muscle tone.

They used full manual guidance to teach four play actions: grasp a block, turn a page, press a button, and hammer a peg.

Every session gave 30 guided reps in a row. The team recorded how many tries the child needed to do each action alone.

The toddler learned every action. The first skill took the longest; later skills took fewer trials.

Learning speed went up as the study moved on.

Mosk et al. (1984) showed that stimulus shaping beats plain prompting for motor skills. Kusano used full hand-over-hand guidance, yet still saw quick gains. The difference: the trisomy 18 child needed the extra support because of severe hypotonia.

Hake et al. (1972) also used hand guidance to teach spoon use. Both studies kept brief praise or food after each response. The pattern is clear: when muscle tone is poor, full manual help plus small reinforcers works.

Bennett et al. (1973) warned that skills may not spread without extra planning. Kusano did not test generalization, so follow-up work should check if the child uses the actions with new toys or people.

You now have a simple recipe for hypotonic toddlers: 30 full-guidance reps, one after another, with a quick treat or cheer. Start with easy grasping, then move to more complex play steps. Track trials to criterion; expect the second and third actions to move faster.