So stupid...
Besides the fact that every character in this movie suffers from a bad case of "Don't just do something, stand there!" all it takes is a simple google of dopamine, serotonin and adrenaline to find that these biochemicals can be generated from SO many things other than inflicting physical pain. That percentage counter should have been going up from the start just by them being there because they were freaked out. Not to mention there are PLENTY of ways to cause someone pain without physically mutilating them.
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