Studies have repeatedly noted that exposure to media violence can be linked to numerous physical and mental health problems for children and teenagers.
Children and teenagers spend more than six hours a day in contact with entertainment media. A large portion of that media includes violence and, more specifically, interpersonal violence. This type of violence is now considered a greater health risk to the pediatric population than most diseases.
Children learn by observing. They cannot differentiate between fantasy and reality or between good and bad portrayed in the entertainment media. They tend to imitate what they see and then it becomes their behavior. This can lead to bullying and aggressive behavior. Also, it can result in nightmares and cause unnatural fears.
Entertainment media does not lay equal emphasis on the harmful consequences of being violent. Instead of showing pain and suffering associated with violent behavior, it glamorizes and rewards violent behavior. Hence, children tend to adapt to these aggressive and antisocial behaviors, and get desensitized emotionally.
A lot of parents find rating system unreliable and confusing. There is a different method to rate distinct media like television, movies, music, video games. Many parents are not familiar with V chip ( Viewer control chip) in the televisions.
Policy Statement on Media Violence, states "Because Children have high levels of exposure, media have a greater access and time to shape young people's attitudes and actions than do parents or teachers, replacing them as educators, role models, and the primary sources of information about the world and how one behaves in it."
The American Academy of Pediatrics recommends that parents should help their children control their time, involve them in alternative activities, remove electronic devices from their rooms, watch programs with them, help them choose good programs, avoid screen media for children less than 2 years of age, and be a good role model for them.
Summary retrieved from http://pediatrics.aappublications.org/content/124/5/1495.full
American Academy of Pediatrics. Policy Statement - Media Violence
Council on Communication and Media