This was actually the study I was thinking of. I don't believe I've read any from the military now that I've checked, but I wouldn't be surprised if their concl

This was actually the study I was thinking of. I don't believe I've read any from the military now that I've checked, but I wouldn't be surprised if their conclusion was based on lack of sleep due to the military giving Dexedrine to pilots for alertness on long missions (which is to be expected; lack of sleep and not eating is not a safe way to use stimulants)