Evidence implicates the anterior cingulate (ACC) and insular cortices (InC) in human´s empathy behavior. We recorded unit activity in these regions of a rat either receiving noxious heat-pulse stimulation to its own forepaw or observing another rat under the same stimulation. Many ACC and InC neurons of an observer rat altered their activities as it approached another rat in pain (social approach). Further, to the pain stimulation applied to self or to others, some of these neurons had similar responses (shared-response), while others showed opposite ones (anti-response). To better study the function of these neurons, we used an empathy-related paradigm in which a freely moving rat rescues a cospecific from a restraining trap (Bartal et al., Science 334: 1427, 2011). Rats were first trained to open the trap and then implanted with stainless steel microwire electrodes in their ACC, InC or motor cortex (MI). A wireless telemetry system was used to record the neuronal activities of the implanted rat. Rats rescuing specifically a trapped rat showed more social approach to a pain suffering rat than those opening gates non-specifically for objects. In the ACC and InC, 25-30 % neurons showed activity changes 0-5 s prior to a rescue action whereas MI neurons showed activity increased around the gate-opening behavior. Most interestingly, the shared- and anti-response neurons reacting to self and other´s pain showed changes in ensemble activity just prior to the rescuing behavior. These findings suggest that a significant portion of ACC and InC neurons in the rat are engaged when observing a conspecific under stress or pain. These neurons may contribute to the empathy-like behaviors of the rat.