Apparent sex differences<\/strong><\/h4>\nThe maps revealed that each region tended to have the same developmental path as its counterpart in the cortex\u2019s opposite hemisphere. Sex differences were apparent too. Even when controlling for sex differences in overall surface area \u2013 male brains having greater area \u2013 there remained differences in multiple regions. For example, the medial prefrontal region in the left hemisphere, which is believed to host important functions such as attention and working memory, became proportionately larger in males early in the second year of postnatal life.<\/p>\n
The analysis also showed that the patterns of cortical surface area expansion in this early period of life were very different from the patterns of cortical thickness development, suggesting that these two measures of brain development involve distinct mechanisms.<\/p>\n
All in all, Li said, the mapping provides fundamental new insights into brain development.<\/p>\n
He and his team now plan to extend this approach with MRI scan datasets that start at earlier ages and end at older ones. They also hope eventually to study scan datasets covering children who have autism-spectrum or other neurodevelopmental conditions. Such analyses might offer not only clues to the origins of these conditions, but also the identification of early signs or biomarkers, which in the future could be used to administer early and more effective treatments.\u00a0<\/em><\/p>\n