You wouldn’t likely be able to just dissolve anhydrous caffeine powder in water and keep yourself blinded; it’s incredibly bitter (second only, in my experience, to tongkat ali / eurycoma longifolia root powder).
You just need a similarly bitter placebo. Make (sugar+caffeine) and (sugar+quinine)* such that you can’t tell the difference and ask a friend put to them in two bottles labeled with “A” and “B”.
(*: Quinine is probably a bad choice for a placebo, since it has its own effects that might confuse the results. It’s just the first thing that came to mind that’s bitter.)
You wouldn’t likely be able to just dissolve anhydrous caffeine powder in water and keep yourself blinded; it’s incredibly bitter (second only, in my experience, to tongkat ali / eurycoma longifolia root powder).
You just need a similarly bitter placebo. Make (sugar+caffeine) and (sugar+quinine)* such that you can’t tell the difference and ask a friend put to them in two bottles labeled with “A” and “B”.
(*: Quinine is probably a bad choice for a placebo, since it has its own effects that might confuse the results. It’s just the first thing that came to mind that’s bitter.)