Bimanual coordination in typical and atypical infants: movement initiation, object touching and grasping.

Carolina et al. (2014) watched babies reach for toys with both hands. They compared typical babies to babies with Down syndrome.

The team filmed how the infants started moving, touched the objects, and grasped them. They looked for smooth, planned hand use.

Typical babies began to plan which hand to use before they touched the toy. Their hand teamwork got cleaner each try.

Babies with Down syndrome did not plan ahead. They used one hand to fix the other hand’s mistake. Their hands worked like two separate tools, not one team.

Brisson et al. (2012) saw the same missing plan in babies later diagnosed with autism. During spoon-feeding, these babies rarely opened their mouth early. Both studies show that when a diagnosis is present, early motor anticipation is missing.

Myers et al. (2018) followed Down syndrome babies into toddler years. They found that teaching the babies to respond to joint attention helped language more than smiling at them. Taken together, motor coaching plus joint-attention games may pack a double punch.

Kınacı-Biber et al. (2026) scanned school-age kids with Down syndrome and found thinner lower-leg muscles and shorter steps. Weak hand coupling in infancy may be the first sign of a body-wide motor pattern that later shows up in walking.

Start motor goals early. Watch how infants move both hands toward one toy. If you see fixing instead of planning, add bimanual play such as pulling apart Velcro blocks or turning a large knob. Pair the play with joint-attention trials. Small tweaks in baby sessions can build smoother hand teamwork and may boost later language and gait.