Avatars, methods, apparatuses, computer program products, devices and systems are described that carry out presenting to at least one member of a population a plurality of avatars associated with at least one instance of media content; measuring at least one physiologic activity of the at least one member of the population, the at least one physiologic activity proximate to at least one presented avatar among the plurality of avatars associated with at least one instance of media content; associating the at least one physiologic activity with at least one mental state; and identifying at least one instance of media content based on the at least one mental state.