Figure 2a:

(a) Bar graph shows total impaired and nonimpaired fighters who were included for classification. Subjects in each fighter population were divided into training (60%; 110 of 182 nonimpaired and 55 of 91 impaired fighters), validation (20%; 36 of 182 nonimpaired and 18 of 91 impaired fighters), and testing (20%; 36 of 182 nonimpaired and 18 of 91 impaired fighters) sets. Training and validation sample set were shuffled 10 times to estimate best training parameters. Numbers represent actual number of subjects in each set. (b) Pipeline used to generate features from diffusion-weighted and T1-weighted MR imaging is shown. Brief description of classifier for which least absolute shrinkage and selection operator (LASSO) and radial basis functional networks (RBFNs) were used, and imaging features associated with cognition in our cohort of active professional fighters, overlaid on Montreal Neurological Institute 152 template, is also shown. AAL = anatomical atlas labeling, MD = mean diffusivity, DTI = diffusion-tensor imaging.