A very interesting studies, I especially like the fact that they got the idea to give Oxytocin to the test subjects.
I believe that punishing a wrongdoer and helping a victim have separate but equally important goals. Punishing a wrongdoer has (or at least should have) a goal of setting an example so that the potential for future wrongful actions by the same or other wrongdoers are mitigated. Helping a victim has a goal of making things right again and creasing a feeling of safety in the society.
Revenge should not play a part in neither of these responses to wrongdoing.
I agree. And helping a victim is good to help heal them. Revenge is what? Too extreme of a consequence applied to a wrongdoer by the victim?
There is an interesting branch of psychotherapy called Rational Emotive Behavior Therapy (REBT). It's underlying concept is that we should not act impulsively based on our emotions, but use our rational mind instead.
This can also be applied to revenge. I think that revenge should not have a goal to hurt the wrongdoer, but only to mitigate the potential for future wrongful actions. With that sort of mindset, instead of harsh punishment for the sake of victim's vengeful pleasure, a just preventive punishment for the sake of setting an example and preventing similar crimes can be chosen. I hope that this makes sense. : )