The project was divided into two phases, with the first occurring in February -November 2014 and the second occurring February - December 2015. The two phases were similar in structure and goals/hypotheses, but had several methodological differences in terms of interventions, arms, and outcome measures. This document contains information pertinent to only the 2014 phase, which examined the relative contributions of physical fitness intervention, video-game based training, and high-definition transcranial direct-current brain stimulation (HD-tDCS) to the improvement of Gf/ARP, executive function, working memory, relational memory, physical fitness level, and brain structure/function.