Laterality of finger movements in preterm infants.

The laterality of head position, spontaneous finger movements, hand-face contact, and hand-mouth contact was studied in low-risk preterm infants of 31 to < 37 weeks postconceptional age (intrauterine + neonatal period at time of study). The head was predominantly turned towards the right side during the preterm period. Hand-mouth contact was more frequent on the right side and coincided well with the side to which the head was turned. Other hand movements, too, were more frequent on the right side than on the left, but these were also seen in the fingers contralateral to the direction in which the head was turned. These findings suggest that even before birth a spontaneous preference for head position is present and is already associated with asymmetry in coordinated finger movements.