Sentence:  Depictions of <WSD>agonic</WSD> displays, on the other hand, increased from the opening phase of the campaign to the debate period and then droped off as Election Day approached. The drop-off in the last stage of the campaign supports the expectation that expressive behavior would be more positive and less varied over time, with the added nuance that <WSD>agonic</WSD> displays increased in the debate period before tapering off. 
Meaning of the word marked with <WSD> tags:  Of a mode of social interaction based on threats, displays of power, or inducements of anxiety.