In recent years, social and developmental psychologists have increasingly studied vicariously induced emotional states. This attention to how individuals respond to other's emotional states and conditions reflects the recognition that emotions are frequently embedded in social interactions (see Eisenberg & Fabes, 1992). Individuals must learn to deal not only with their own directly induced emotions, but also with their reactivity to the emotions of others.

Several types of vicarious emotional responses have been differentiated. For example, empathy is defined as an emotional response that is based on the apprehension of another's emotional state or condition and is similar to the emotion of the other person. Sympathy is defined as feelings of sorrow or sadness for another, whereas personal distress is a vicariously induced aversive emotional reaction such as anxiety or discomfort. The degree to which individuals are willing or able to display vicariously induced emotional reactions varies considerably from person to person. Moreover, the ways in which individuals display these reactions (e.g., verbal and/or nonverbal reactions) also varies considerably from person to person.

In research on vicarious emotional responding, several types of measures may be obtained. For example, subjects often are asked to report their emotional reactions verbally when exposed to needy or distressed people. In addition, facial reactions sometimes are used to index vicarious emotional reactions, particularly in studies involving children.