Previous research studies have shown that advertisements that elicit high arousal positive emotions can have a contagious effect in social media. This dissertation attempts to advance understanding of the effect of specific high arousal positive emotions on viral sharing, employing appraisal theory of emotions, according to which, emotions incite action tendencies that influence behavior. A qualitative and a quantitative study were conducted to determine the motivations for sharing ads. Four motivations were identified in relation to sharing ads, emotional altruism, functional altruism, affiliation and status. A quantitative study and an experiment followed, to examine the effects of two high arousal positive emotions, awe and affection, on viral sharing. The quantitative study explored the action tendencies associated with awe and affection in viral advertising and the experiment considered the influence of awe and affection emotions on sharing motivations. The results illustrate that both awe and affection activate connectedness action tendencies (awe, to be connected to the world, and affection, to display warmth/affection or to be close to others), and both these emotions lead to sharing of viral ads in social media more for emotional altruism and affiliation motivations, rather than for status or functional altruism motivations.