This invention provides user interfaces that more intuitively display physiological data obtained from physiological monitoring of one or more subjects. Specifically, the user interfaces of this invention create and display one or more avatars having behaviors guided by physiological monitoring data. The monitoring data is preferably obtained when the subject is performing normal tasks without substantial restraint. This invention provides a range of implementations that accommodate user having varying processing and graphics capabilities, e.g., from handheld electronic devices to ordinary PC-type computers and to systems with enhanced graphics capabilities.