The biological origins of rituals: An interdisciplinary perspective.

Ritual behavior is ubiquitous, marking animal motor patterns, normal and psychopathological behavior in human individuals as well as every human culture. Moreover, formal features of rituals appear to be highly conserved along phylogeny and characterized by a circular and spatio-temporal structure typical of habitual behavior with internal repetition of non-functional acts and redirection of attention to the "script" of the performance. A continuity, based on highly conserved cortico-striatal loops, can be traced from animal rituals to human individual and collective rituals with psychopathological compulsions at the crossing point. The transition from "routinization" to "ritualization" may have been promoted to deal with environmental unpredictability in non-social contexts and, through motor synchronization, to enhance intra-group cohesion and communication in social contexts. Ultimately, ritual, following its biological constraints exerts a "homeostatic" function on the environment (social and non-social) under conditions of unpredictability.