Fig. 1.

The empathic-pain task. Participants viewed continuous live video feeds (a) of the hand of the study partner (confederate) and then their own hand, in separate runs. On each trial (b), a variable anticipation period was followed by the administration or omission of painful pressure stimulation to the right thumbnail. An audio cue at the beginning of the anticipation period indicated whether the trial was safe or had the potential for pain. A second audio cue indicated whether or not painful pressure was administered.