Habituation of visual evoked potentials in healthy infants and in infants with periventricular leukomalacia

Objective To investigate whether habituation of flash visual evoked potentials is already present during the first 3 months of life, and to explore differences between healthy infants, term infants with periventricular leukomalacia (PVL), and preterm infants with PVL. Methods Referential recordings to stimuli consisting of photic stimulation presented in blocks were obtained. A total of 25 blocks, 15-stimuli each, were presented. Intrablock and interblock habituation effects were analyzed. Results In healthy infants of 42–50 and 51–58 weeks of post-conceptional age (PCA), a negative central component (NCC) showed a significant decrease in amplitude due to stimulus repetition. NCC habituation was also observed in term infants with PVL at 51–58 weeks of PCA, but not in term infants with PVL at 42–50 weeks of PCA. NCC habituation was not apparent in preterm infants with PVL. Conclusions These results suggest that the neural mechanisms of visual habituation are normally present during the first month of life, but the presence of PVL delays the emergence of these mechanisms, particularly in preterm infants. Significance The habituation of flash visual evoked potentials may be developed into a reliable tool to examine normal and abnormal development of early neural processes.