As I recall, the CIA did do a fair amount of this research on this, up to and including implanted cortical stimulators, which created some serious backlash.
Getting prescribed "on/off" switches in pill form is a well-known thing in the military. You just can't do combat air patrol over remote areas of Asia without some uppers. This quickly went from the pilots (mid-grade officers) and other fight crew, to being adopted by folks who have to go halfway around the world routinely (flag officers).
It's an active topic of conversation, some do, some don't. As a military physician who was a line officer and has been through 5 years of graduate medical education (internship + residency), and now occasionally has to do those round-the-world trips, it's not clear to me that there's an obvious right answer in policy or per-person. We (leaders and followers alike) expect leaders to function at the outer limits of human capacity, and have for a long time. I can tell you this: it doesn't get easier with age: a fairly common definition of success as a leader is proving your ability to take on more responsibility, so the more you do, the harder it gets. So avoid starting early.
Getting prescribed "on/off" switches in pill form is a well-known thing in the military. You just can't do combat air patrol over remote areas of Asia without some uppers. This quickly went from the pilots (mid-grade officers) and other fight crew, to being adopted by folks who have to go halfway around the world routinely (flag officers).
It's an active topic of conversation, some do, some don't. As a military physician who was a line officer and has been through 5 years of graduate medical education (internship + residency), and now occasionally has to do those round-the-world trips, it's not clear to me that there's an obvious right answer in policy or per-person. We (leaders and followers alike) expect leaders to function at the outer limits of human capacity, and have for a long time. I can tell you this: it doesn't get easier with age: a fairly common definition of success as a leader is proving your ability to take on more responsibility, so the more you do, the harder it gets. So avoid starting early.