From the Nuremberg Trials to Stanley Milgram's famous experiments at Yale University, people have long claimed no responsibility because they were "just following orders." And now, a new neuroscience study published in Current Biology finds that our brain processes actions differently in two implicit, measurable ways when we are following orders.
Subjects were paid for pressing a button that would either inflict a mild electric shock (or a monetary penalty) on someone else. After pressing the button, a tone played, and the participants had to estimate how long it had been between pressing the button and hearing the "confirmation" tone.
In half of the trials, the participants were told, firmly, by a scientist to press the button.
Here's the interesting part: subjects acting under orders felt that more time passed between pressing the button and hearing the tone. In other words, following orders "distanced" the actor from her action, a subjective measure of responsibility.
Secondly, the authors also measured brain activity after the action by recording the amplitudes of electroencephalogram (EEG) potentials. They found that the potential amplitudes were significantly lower in the coercive condition-- regardless of whether the action was associated with a painful shock to their partner! That is, people thought less about their action when they had been ordered to do it.
Unsurprisingly, the participants also rated themselves as being less responsible when they were acting under orders. The exciting contributions of this research are the two implicit measures-- thinking more time had passed, and demonstrating less brain activity-- that would have been more difficult to consciously manipulate.
In the original study, the authors write:
"... our result clearly suggests one reason why so many people can be coerced. Specifically, coercion may reduce the linkage that normally binds the experience of actions to their outcomes. Indeed, emotional distancing from distasteful outcomes of one’s own necessary actions forms a specific part of training and professional culture in medicine  and in the military . Training effects might also work in the opposite direction: learning the true valence of one’s actions’ outcomes might potentially make the sense of agency more resilient to the undermining effects of coercion."
Perhaps, then, formal training structures to engender rule-following are also simultaneously engendering a lack of agency.
Obviously, this research in no way is meant to excuse people from responsibility for their actions. Instead, it demonstrates the measurable underpinnings of our subjective feeling: that we are less responsible for actions undertaken under orders.
Neuroscientists have added fresh insight to the observation that people are surprisingly willing to hurt others if they are ordered to do so. This was famously shown by psychologist Stanley Milgram in the 1960s. In the new study, subjects in pairs were paid to deliver mild electric shocks to one another. If they were instructed to administer the shocks, they sensed more of a delay before the jolt was delivered, compared to when they made their own decisions. Researchers regard this timing judgment as an indicator of how responsible we feel for our actions.