Scholarly definitions of emotion mirror our everyday experiences. Emotion is an intense reaction to an event that involves interpreting event meaning, becoming physiologically aroused, labeling the experience as emotional, managing reactions, and communicating through emotional displays and disclosures (Gross, Richards, & John, 2006). This definition highlights the five key features of emotion. First, emotion is reactive, triggered by our perception of outside events (Cacioppo, Klein, Berntson, & Hatfield, 1993). A friend telling you that her cancer is in remission leads you to experience joy. Receiving a scolding text message from a parent triggers both your surprise and your anger.

A second feature of emotion is that it involves physiological arousal in the form of increased heart rate, blood pressure, and adrenaline release. Many researchers consider arousal the defining feature of emotion, a belief mirrored in most people’s descriptions of emotion as “intense” and “hot” (Berscheid, 2002).

Third, to experience emotion, you must be-come aware of your interpretation and arousal as “an emotion”—that is, you must consciously label them as such (Berscheid, 2002). For example, imagine that a friend shares an embarrassing photo of you on Facebook—an image that he promised you he wouldn’t post. The moment you see it, you know your trust has been betrayed. Your face grows hot, your breathing quickens, and you become consciously aware of these physical sensations. This awareness, combined with your assessment of the situation, causes you to label your experience as the emotion “anger.”

Fourth, how we each experience and express our emotions is constrained by historical, cultural, relational, and situational norms governing what is and isn’t appropriate (Metts & Planalp, 2002). As a consequence, once we become aware that we’re experiencing an emotion, we try to manage that experience and express that emotion in ways we consider acceptable. We may allow our emotion to dominate our thoughts and communication, try to channel it in constructive ways, or suppress our emotion completely. Emotion management results from the recognition that the totally unrestrained experience and expression of emotion will lead to negative consequences.

Finally, when emotion occurs, the choices you make regarding emotion management are reflected outward in your verbal and nonverbal displays, in the form of word choices, exclamations or expletives, facial expressions, body posture, gestures (Mauss, Levenson, McCarter, Wilhelm, & Gross, 2005), and even in the emoticons that accompany your text and e-mail messages.

Another way in which emotion is communicative is that we talk about our emotional experiences with others, a form of communication known as emotion-sharing. Much of interpersonal communication consists of emotion-sharing—disclosing emotions, talking about them, and pondering them. Studies on emotion-sharing suggest that people share between 75 and 95 percent of their emotional experiences with at least one other person, usually a spouse, parent, or friend (Frijda, 2005). The people with whom we share our emotions generally enjoy being confided in. Often, they share the incident with others, weaving a socially intimate network of emotion-sharing.

Sometimes emotion-sharing leads to emotional contagion , when the experience of the same emotion rapidly spreads from one person to others. Emotional contagion can be positive, such as when the joy you experience over an unexpected job promotion spreads to your family members as you tell them about it. At other times, emotional contagion can be negative, such as when fear moves quickly from person to person in a large crowd.