entertainment media, including television, movies, music, cell phones, video games, and the Internet (Kaiser Family Foundation, 2010). Media content is also a concern: more than 800 violent acts are shown on television each hour in the United States; about 15 percent of music videos portray interpersonal violence (Beresin, 2010); and two-thirds of the 97 percent of children who play video games play games that may include violence (Lenhart et al., 2008). However, data on the prevalence of firearm violence in the media are absent. The following section reviews potential associations of exposure to media violence and violent acts, but is not specific to firearm violence.
Short-Term Experimental Studies on Exposure to Media Violence
The vast majority of research on the effects of media violence is based on short-term laboratory or field experiments. These studies examine short-term effects of media exposure on physical and verbal aggressive behavior, thoughts, and emotions; hostility; fearful behaviors; physiological arousal (e.g., changes in heart rate); the tendency to mimic behavior; and changes in helpful behaviors, empathy, and pro-social behaviors in both males and females (Anderson, 2004; Anderson and Bushman, 2001; Anderson and Dill, 2000; Anderson et al., 2003, 2010; Bartholow et al., 2005; Browne and Hamilton-Giachritsis, 2005; Bushman and Huesmann, 2006; Fuld et al., 2009). Fewer studies examine the link between short-term exposure to media violence and violent behaviors such as arguing, fighting, aggravated or sexual assault, shooting, stabbing, and robbery (Gentile et al., 2004; Ybarra et al., 2008).
These short-term experimental studies consistently document significant effects of experimentally manipulated media exposure on a wide range of short-term outcomes. Results are broadly similar in studies of television and film violence (Bandura et al., 1963; Bushman and Huesmann, 2001; Huesmann et al., 2000; Paik and Comstock, 1994; Wood et al., 1991) and violent video games (Anderson, 2004; Anderson and Bushman, 2001; Anderson and Dill, 2000; Bartholow et al., 2005; Gentile et al., 2004). However, effects vary as a complex function of interactions among media content, viewer characteristics, and social contexts (Anderson et al., 2003) and are open to a number of interpretations other than those