Visual evoked potentials(VEPs) are the cerebral electrical activities recorded from the occipital scalp following a flash or pattern stimulation and can detect the lesions of sensory visual pathways. Although the VEPs change with the maturation of CNS in children, a few studies have documented the maturational changes in premature infants. Using the light- emitting diode goggles, VEPs were studied in 131 neurologically intact infants of 28∼41 weeks gestational age or 34∼59 weeks postmenstrual age.

The VEPs were analysed by three waveforms; normal, abnormal, and flat, and four patterns; N₃₀₀, P₂₀₀-N₃₀₀, P₁₀₀-N₁₅₅-P₂₀₀-N₃₀₀, and P₁₀₀ pattern. Normal waveforms were 63 of 131 VEPs(48.1%). Of the normal waveforms, N₃₀₀ patterns were 38.1%, P₂₀₀-N₃₀₀ 36.5%, P₁₀₀-N₁₅₅-P₂₀₀-N₃₀₀ 19.0%, and P₁₀₀ 6.4%. Each pattern correlated with the postmenstrual age. These findings support the hypothesis of VEP pattern changes according to the maturation of the visual system with age.