Most researchers agree that heavy television viewing tends to impair educational attainment and contributes to sex role and ethnic stereotyping. There is far less agreement, however, on the impact of violent imagery outside the clinical setting, primarily because of the difficulty researchers have in measuring the connection between fantasy and real world violence. The group most affected by mass media appear to be black youth. The tremendous growth of the black "underclass" and the increase in violent antisocial behavior among inner city youth are explained in terms of the underclass' distinctive culture rather than in terms of unemployment or welfare alone. By building on self-destructive tendencies and by reinforcing some of the most negative aspects of human nature that already exist in the ghetto, the media have altered the culture and values of inner city youth to the point where antisocial behavior is accepted as the norm. Research on substance abuse shows there is a window of vulnerability between 15 and 18 years when teenagers are particularly vulnerable to outside influences before their values and ideas have fully formed. According to childhood development theories, teenagers have a deep-seated need to emulate others, and examples abound of youth emulating television and movie heroes in real life. Antisocial role models, however, do not totally explain the breakdown of values in the inner city; such variables as alcoholism, drug abuse, illegal weapons, and welfare dependency are also important. The key issue is how to devise social mechanisms that help disproportionately affected communities rebuild individual and community norms. 38 references