That's 99% on that one trait 'inhibition', but very much less on the others. I'm very skeptical that it's all genetic, since they didn't factor out the environ

That's 99% on that one trait 'inhibition', but very much less on the others. I'm very skeptical that it's all genetic, since they didn't factor out the environment. I can't access the paper right now, but how did they measure the resistance to habit? Did they build up specific habits and then try to break them down, or did they use existing habits, or what?