Ars Technica: Virtual shocks produce real-world distress:

The authors argue that, even with a virtual victim, the distress displayed by the subjects recapitulate what was seen in the classical Milgram experiments. Despite the similarities, however, the subjects were well aware of the nonreality of their actions, as the authors note, "In the debriefing interviews many said that they were surprised by their own responses, and all said that it had produced negative feelings – for some this was a direct feeling, in others it was mediated through a ‘what if it were real?' feeling. Others said that they continually had to reassure themselves that nothing was really happening, and it was only on that basis that they could continue giving the shocks." This constant reassessment of the reality of the proceedings raises questions as to whether these experiments truly can provide us insights into modern maladies such as suicide bombings and football hooliganism.