Lessons from helping behavior in rats.

Helping involves other-oriented actions that have the potential to benefit another. The last ten years has seen the introduction of several experimental paradigms to study helping in rats. In the best characterized of these, a free rat opens a door to release a rat trapped in an acrylic tube or pool of water. Helping is proffered independent of the opportunity to socially interact. Both an absence and an excess of affective arousal or anxiety antagonize helping whereas mild levels of distress facilitate helping. Helping is socially selective and highly sensitive to the social environment with non-helpers antagonizing and additional helpers facilitating another rat's propensity to help.