This shouldn't be surprising, psychologists have known this for a couple of decades. See mood contagion: https://en.wikipedia.org/wiki/Emotional_contagion http

This shouldn't be surprising, psychologists have known this for a couple of decades. See mood contagion: https://en.wikipedia.org/wiki/Emotional_contagion https://en.wikipedia.org/wiki/Emotional_contagion Anger, being a highly negative, high energy-level emotion, is very contagious. People respond differentially to positive and negative stimuli, and negative events tend to elicit stronger and quicker emotional, behavioral, and cognitive responses than neutral or positive events. Thus, unpleasant emotions are more likely to lead to mood contagion than are pleasant emotions. Another variable that needs to be taken into account is the energy level at which the emotion is displayed. As higher energy draws more attention to it, the prediction is that the same emotional valence (pleasant or unpleasant) expressed with high energy will lead to more contagion than if expressed with low energy.