"Emotional contagion is the tendency for two individuals to emotionally converge. One view developed by Elaine Hatfield et al. is that this can be done through automatic mimicry and synchronization of one's expressions, vocalizations, postures and movements with those of another person. When people unconsciously mimic their companions' expressions of emotion, they come to feel reflections of those companions' emotions. Emotions can be shared across individuals in many different ways both implicitly or explicitly. For instance, conscious reasoning, analysis and imagination have all been found to contribute to the phenomenon. Emotional contagion is important to personal relationships because it fosters emotional synchrony between individuals. A broader definition of the phenomenon was suggested by Schoenewolf: "a process in which a person or group influences the emotions or behavior of another person or group through the conscious or unconscious induction of emotion states and behavioral attitudes""
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