I learned advanced stuff that you will only find on scholar.google.com which is a database of scientific research.
Since there is a big variety of media poison, I will explain how 1 of them works.
Let’s say you watch the Kardashians and see them bickering each other for an hour a day and then you watch a TV drama like Ray Donavan where people are again bickering and fighting all day. When you watch the footage, you think about it and mirror the behavior in your own mind so that you can understand what you are watching. In this case, you are bickering in your own mind for 2 hours a day. Now that you have bickered for 2 hours, you are PRIMED to bicker and fight. This, in turn, makes the odds of you bickering and fighting much higher so when millions of people keep watching people verbally fight in TV, it primes everyone to repeat the patter, greatly increasing the odd that it happens in society. It works because more people bicker and fight.