Visual function in the newborn: a study of preterm and full-term infants

Visual function has been studied in the preterm newborn infant by the visual orientation (tracking) technique of the Brazelton neurobehavioral assessment, and the pattern preference and fixation technique of Fantz. By both these methods we have been able to document the presence of discriminative visual function by 31-32 weeks gestation, and by 34 weeks the pattern reaches a maturity comparable to the full-term infant. Sequential studies at weekly intervals of preterm infants ranging in gestation from 28-32 weeks showed a similar pattern of development of visual function to the newborn infant of equivalent postconceptional age. Comparative studies of the two methods of assessment of visual function in the same infants have shown surprisingly little correlation. Assessment of visual function in the preterm newborn infant is a valuable milestone and, as in the case of other developmental milestones, aberrations may reflect a deficit in visual function itself, or a more broad based deficit in neurological function or a secondary response to a generalized illness in the newborn infant.