1. The document analyzes how collective attention on Twitter was entrained at different timescales during the 2012 US presidential debates. 2. It found short-term interactional entrainment aligned with who was talking and interrupting, slower entrainment to salient debate content, and long-term rise and decay in overall attention across the debates. 3. Models combining interactional dynamics, content mentions, and overall attention patterns predicted the flow of collective attention on Twitter reasonably well and suggest attention was entrained at multiple interconnected timescales during the highly salient media events.