For years blacks and other minorities were portrayed in movies and television mostly as maids, butlers and other servants. Today, it is common to see these same people portrayed as doctors, lawyers and judges.
For years women were portrayed mainly as housewives, and if they did have a job, it was often as a barmaid/prostitute in a western. Today, women are often portrayed having a family and working in respectable jobs, and handling both.
For years the mentally retarded (developmentally disabled) were portrayed as less than a whole person, and actually called "dummy" in many movies and television shows. Today, they are often portrayed with much more sensitivity.
For years, gays were portrayed as deviants and criminals, people to be feared. Today, gay characters are usually given the same respect as their straight peers.
For years, people with mental illness were portrayed in movies and television mainly as psychopathic killers whose one goal in life was to torture and murder as many people as possible. Today, it's still the same!!!
For example, I was recently watching an episode of The Practice, ABC's critically acclaimed drama. The minute they mentioned that one character on this episode was schizophrenic, I turned to my wife and said, "I bet any amount of money in the world that he ends up to be a mass murderer and a deviant." Sure enough, the character ended up murdering 10 people, including his own psychologist. He also liked to pull out the fingernails of each victim and collect them.
Unfortunately, this is one of many, many examples. The bottom line is that if the only images people are subjected to on TV and in the movies of mental illness are like the examples shown above, of course they are going to believe that this is the norm rather than the exception.
The media has come a long way in showing minorities, women, mentally retarded individuals and gay persons in a much more honest and truthful light. It's about time they did the same for people with mental illness.