Perhaps the most important factor that can influence how a person perceives information from the media is education. This can be education in general, but it can also be education that is specific to how to interpret what one hears or sees in the media.
In general, the more knowledge one has, the more skeptical one is able to be. If we have more knowledge, we are more likely to be able to question the validity or plausibility of what we see in the media. We are more likely to have information that would give us reason to doubt that what the media is saying is exactly accurate and unbiased.
In addition, education about the predilections of the media can help us to perceive the information we see in the media in a more sophisticated way. If we know, for example, that the media is prone to telling stories that make underdogs seem more appealing and more downtrodden, we can perceive the information we get in the media in that light. We can understand that the information is likely to be skewed so as to fit into a set story template that is likely to get more viewers for the news show or more readership for the print media.
In these ways, education is one of the most important factors that affects how we perceive information that we get from the media.