This study was designed to further our understanding of the central role of motivational activation in mediated information processing and media choice. To do this, a dynamic model was developed to formalize the dynamic effects of three basic motivational input variables (arousing content, positivity, and negativity) on four physiological output measures (heart rate, skin conductance level, corrugator activity, and zygomatic activity) and a behavioral choice measure of television channel selection. The input and output variables were selected based on extensive theoretical and empirical research that has explicated static relationships among these variables. In general, the findings of the dynamic modeling approach were consistent with the previous literature using traditional static statistical methods. However, this study also theoretically extended the previous work.