PowerBrainRx, a Hong Kong-based for-profit company, promises to improve cognition. Their Web site lists testimonials, including one from a parent whose children “seemed to have better working memories, improved problem solving ability like mathematics, more logical thinking and better academic performance” following mental exercise training. There are numerous ads for companies like PowerBrainRx on the Internet and on late-night television, but there does not seem to be a lot of research examining the specific programs these companies are selling. How could you design a study for PowerBrainRx that would use a paired-samples t test to analyze the data?