Myelination is essential for normal brain function. The development of myelin begins in the third trimester of pregnancy and enables rapid synchronized communication between different brain regions. During the 3rd trimester of gestation overlapping with preterm birth, the neurodevelopment undergoes intensive cyto and myeloarchitecture changes. The T1/T2 ratio is a surrogate for the degree of myelination but has not been used to study early neurodevelopment. Using T1/T2 ratio, we show the unique spatiotemporal pattern of the cyto and myeloarchitecture changes in preterm neonates. This result may be useful in prediction of neurodevelopmental outcome and functional impairments in preterm survivors.