Dimensional models of emotion suggest that a common and interconnected neurophysiological system is responsible for all affective states.[8] These models contrast theories of basic emotion, which propose that different emotions arise from separate neural systems.[8] Several dimensional models of emotion have been developed, though there are just a few that remain as the dominant models currently accepted by most.[9] The two-dimensional models that are most prominent are the circumplex model, the vector model, and the Positive Activation – Negative Activation (PANA) model.[9]