There are higher-res. Here growth rates are mapped for the corpus callosum , the major fiber tract that communicates information between the two brain hemispheres. The maps are made based on scanning the same child at age 3 and 6, another child at age 6 and 7, etc. There are two major surprises. Here the details of growth rates are revealed for a range of individual children.
Tensor maps allow growth rates to be mapped in an individual child.
They uncover regions in which growth rates are fastest, and visualize changes in these patterns across time. Again, red colors indicate fastest growth in fiber regions that innervate temporo-parietal cortex, a brain region which is functionally specialized to support language function. Note how drastically reduced growth is in the 11-15 year age range, which also marks the end of a critical period when children are most efficient at learning new languages. In a much younger child, different circuits are growing fastest. Here the growth rates are most rapid in fibers that send information to frontal cortex.