The Hypodermic Needle Model Theory

The Hypodermic Needle is classed as a model of communication, rooting back to 1930's the Needle is meant to give a mental image of a message being inserted into the mind of an individual.
The theory is said to be used to infuse messages into an individual, meaning that audiences passively receive the information via the media without any attempt to process the data.

It also suggests that the information being passed from a media text is passed through the mass consciousness of the audience whether they want the information to be there or not, this process could result in character and behavior changes.

This image shows that the needle is inserting into the head, which is what the needle theory is trying to explain.

Something that also can be related to this theory is Propaganda which is a form of communication set out to influence the behavior and attitudes of a Mass media in order for them to make decisions for some cause of problem.
Some images produced are used with loaded messages to get a emotional response rather than a rational one.
For example.....

They use images like this one to influence the audiences decision, using emotional messages to get a positive response to what they are trying to aim at.
the use of bright colours and emotional imagery it leaves the audience no choice to be drawn in by it.