Not wearing a seatbelt is legal in many places, or at least not enforced. And enforcing brain zapping would be even harder, because people do it in the privacy

Not wearing a seatbelt is legal in many places, or at least not enforced. And enforcing brain zapping would be even harder, because people do it in the privacy of their own homes. But the argument isn't about legality. It's whether scientists should work with these people. They are going to brain zap anyway. The scientists have nothing to lose by collecting their data. They could also give helpful warnings and information to limit the harm. But above all don't call them idiots for trying this. There are desperate people with serious conditions that are willing to take a small risk for anything that might help their condition. The medical system is very slow, conservative, and risk averse, in adopting new treatments. So people that want better treatments are forced to take it into their own hands. If doctors offered this treatment today, this wouldn't be an issue.