This is a study in adults ages 40 to 55 to assess the sensitivity of Project: EVO Monitor cognitive measurements to two short-acting cognitively active pharmacological agents, methylphenidate (MPH) and triazolam (TRZ). The participants will receive a placebo, MPH, and TRZ in a randomized order for three in-clinic study days. All drug administration and cognitive testing will take place in the clinic under medical staff supervision. During each study day in the clinic, the participants will use Project: EVO Monitor and do a short digit symbol substitution task (DSST) 8 times over the day. A minimum of 48 hours will be needed between each study day. The investigators plan to evaluate 18 participants in this study.