Behavioral organization in infants can be characterized by the integration and coordination of component behaviors over time, mediated in part by emerging nervous system activity. This study evaluated the organization of behavioral states and the percentages of time spent in particular behavioral states by preterm infants. In addition, the effects of visual stimulation on the organization of behavioral state and on the development of the visual skills in preterm infants was assessed. Twenty preterm infants were observed at the time of admission and discharge from the intermediate unit of a neonatal intensive care unit. Behavioral state was recorded and visual responsiveness assessed on both occasions. For one group of infants, a striped visual stimulus was placed in their incubators following the initial observation, and removed at the time of the second observation. A second group of control infants received no exposure to the visual stimulus. Results revealed that infants who were exposed to a visual stimulus significantly decreased the number of state changes they experienced and had significantly higher visual responsiveness scores than infants who were not provided a visual stimulus. The amount of increase in the percentage of time spent in Quiet Sleep and increase in the state stability score, a measure of consistency among behavioral states, was nominally higher for infants who were exposed to the visual stimulus than for infants who were not allowed exposure to the visual stimulus. These findings indicate that visual stimulation can influence the development of visual responsiveness in preterm infants. Furthermore, exposure to a visual stimulus appears capable of extending the amounts of time that preterm infants spent in particular behavioral states, thus reducing the number of state changes they experience. The significance of these findings is discussed in terms of preterm intervention procedures. In addition, the possible importance of self-regulation of sensory input for preterm infants and the clinical implications of low and high state stability scores are discussed. / Ph. D.