Communication of inflammation

Comments on an article by Silvia Castany et al. Inflammatory processes underlie or contribute to not only a sur prisingly wide array of serious physical and mental disorders, but also play important roles in non-disease-related adaptive neural and biobehavioral processes. One of the most exciting avenues this latter research has taken is in regard to social behavior and communication. We now know, for instance, that experimentally induced inflammatory pain can be transmitted between individuals so that sensitivity to pain increases in uncompromised bystander animals Bystanders also will initiate a limited anticipatory cytokine response when exposed to immune-challenged cage-mates. Social behavior is affected as well in that im mune challenge alters the attractiveness of animals to conspecifics. Most often sick animals are avoided as one would expect, but more interestingly, they sometimes are approached. A recent paper by Castany et al in Brain Behavior and Immunity builds on and advances such findings by showing how inflammation itself might be transmitted from one individual to another for adaptive social purposes. These au thors identify a situation in which inducing inflammation in one set of animals (mouse pups) can prompt a robust and systemic inflammatory response in others (mothers). Furthermore, the dams do not just exhibit increases in basic prosocial responses, such as approach, but rather in the more-complex and clearly adaptive response of maternal caretaking of their dependent young.