Reduced development of cerebral cortex in extremely preterm infants

Most growth in cortical connections and complexity occurs after 25 weeks. T he cerebral cortex of extremely preterm infants when imaged at gestational age 38-42 weeks had less cortical surface area and was less complex than in normal infants born around term (p<0.0148 and p<0.0002, respectively), des pite similar term-corrected cerebral tissue volumes. Since deficits acquire d during critical periods of brain development may be permanent, these resu lts suggest a neural substrate for the neurocognitive impairment that is fr equent among such preterm infants.