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When are the major folds of the human cerebral cortex present during fetal development?
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prenatal development
An ultrasound image of a human fetus.
During fetal development, the formation of convolutions in the cerebral cortexāspecifically the gyri and sulciāis a key aspect of brain maturation. While the central and calcarine sulci become discernible by the fifth fetal month, all major folds of the human cerebral cortex are normally present by the seventh month of development. Many minor sulci and gyri continue to appear after birth.1