Most "clever and ultra violent" criminals by far are in fact sociopaths. Sociopathy does correlate with a severe lack in executive function, but the causal mec

Most "clever and ultra violent" criminals by far are in fact sociopaths. Sociopathy does correlate with a severe lack in executive function, but the causal mechanism is very likely different from what we see in ADHD - it's probably a sort of "callousness towards oneself" stemming from the sociopath's exceedingly-poor emotional palette, that also leads to their callous behavior and lack of empathy towards others.