Figure 9.

Empathy for pain: heart rate. (a,b) The first dotted vertical line shows the onset of the stimulus cue. The second dotted vertical line shows the onset of the shock and the shock cue. The grey area shows the time window for which signal was averaged. (c,d) In the self high condition, there was a large peristimulus peak. We did not include this peak in the time window for further analysis, because it may represent non-cardiac signal sources such as the electrical pain stimulus itself and associated muscle activity.