Median population DVHs for patients exhibiting no decline (solid line, blue) compared with patients exhibiting decline (dotted line, red) for the following brain substructures and neurocognitive outcomes: (A) the left hippocampus and associative memory, (B) the right hippocampus and associative memory, (C) the CC genu and composite processing speed, (D) the left hippocampus and working memory, (E) the right hippocampus and working memory, (F) the CC body and composite processing speed, (G) the CC splenium and composite processing speed, (H) the right frontal WM and composite processing speed, and (I) the left frontal WM and composite processing speed. The shaded region represents the 25th-75th percentile. CC, corpus callosum; DVH, dose–volume histogram; WM, white matter.