Perinatal stroke causes abnormal trajectory and laterality in reaching during early infancy

• We investigated trajectory and laterality during the emergence of reaching in infants with perinatal stroke and infants with typical development.
• Infants with typical development demonstrated a primarily quadric model of reaching and age whereas infants with perinatal stroke demonstrated a linear model.
• Infants with perinatal stroke demonstrated asymmetry in reaching behaviors by contacting the toy less and for a shorter duration with their affected arm.
• Atypical laterality may be an important factor in the presentation of early neglect.

The developmental progression of reaching and early signs of upper extremity neglect is common concern for infants at risk for hemiparesis and cerebral palsy. We investigated the emergence of reaching and laterality in infants at risk for hemiplegic cerebral palsy. Eight infants with perinatal stroke (PS) and thirteen infants with typical development (TD) were assessed bimonthly from 2 to 7 months of age for 10 visits per infant. Reaching number and hand-toy contact duration were measured. Infants with PS demonstrated a linear trajectory of reaching behaviors with asymmetrical upper extremity performance. Infants with TD demonstrated a linear and quadratic trajectory of reaching behaviors and symmetrical upper extremity performance over the same age range. These results suggest that infants with PS have delay reaching and early signs of neglect not currently accounted for in clinical practice.