I am writing a research paper on Communication Apprehension in Classroom Interaction.
My professor approved my general topic, but she stressed the fact that I have to come up with a new scope within the same field because it's already been investigated. How can I do that?
And how can I introduce a new hypothesis once I examine all the research studies done before on my topic?
Writing a successful research paper means one of two things. Either you can come up with some new idea, filling a gap in the existing scholarship, or you can argue that the existing scholarship is in some way wrong. If someone has already given a perfectly good account of an idea or topic, there is no reason anyone should read another paper just repeating the same information.
This leads to the major change from basic level undergraduate to more advanced classes. In introductory classes, you write papers to prove that you have done the assigned reading; your teacher reads them to assess your knowledge, not because you necessarily have created something worth reading by anyone not paid to read it. At a more advanced level, you are writing for an audience of other scholars who may be working in fields in which hundreds of papers are published each year. Thus for your paper to be worth reading, you need to convince potential readers that you have something that adds to the existing body of scholarship and is worth their time investment.
At this point in your career, you are unlikely to create a complete new theory of communication apprehension. Instead, you should carefully read over existing scholarship and see if there is some small gap you could fill. For example, if existing scholarship has looked at communication apprehension in Navajo students but not covered Hopi students, you could design a small study concerning Hopi students. Alternatively, you might use a Blackboard discussion forum in one of your classes and look at rates of participation by gender according to the current work on the intersection of gender and communicative behavior. In general, the narrower the focus of a paper, the easier it is to write.
The more you read over the existing scholarship and the more familiar you become with the field, the more ideas you will have. Thus as a matter of process, I'd recommend spending a week or so reading over 20-30 recent articles as a starting point for developing a thesis.