Temporal Selective Exposure: How Partisans Choose When to Follow Politics

It is widely theorized that echo chambers contribute to polarization, yet behavioral evidence of partisan selective exposure in the real world is surprisingly tenuous. Why do partisans have polarized perceptions even though they have relatively balanced media diets? We argue that partisans vary in terms of when they pay attention to the news, not just in terms of the ideological media sources they follow. By leveraging national election surveys across seven decades, as well as the sudden change in the economic news environment that was induced by the collapse of Lehman Brothers, we show that partisans vary their political attentiveness and media consumption in response to whether news events are congenial to their party. These findings suggest that partisans can subject themselves to biased information flows even if their media diets are balanced. The temporal dynamics of selective exposure carry important implications for mass polarization.