sounds like an awesome topic! i'm currently overseas on a research project as well! I've also worked overseas in both EU and non-EU countries on an internship level and would say the best way to get information is just to call up the embassy especially since Norway is just an EEA member as opposed to the EU, these requirements often change (the visa regulations have since changed in the non-eu country i worked in three years ago) and you should have the details in writing when you arrive. That being said, employers are often very flexible and I know many international interns that get paid "under the table" for their 3 month summer positions b/c the paperwork is simply a hassle (for example, eu member states may have to "prove" no suitable EU-members are able to fill the position before hiring a non-EU member) and you can stay in the country that long w/ just a travel visa anyway. If you're on a research fellowship, especially if its funded by the government, they're usually very helpful in getting all of the visa stuff facilitated and if you have a overseas foundation contact, they would probably be a good resource as well. best of luck!

Well I looked and there is a visa exemption for 90 days since I have a US Passport, so I don't think I'm going to have to do anything there unless I end up deciding to stay more than 3 months. My research fellowship is funded by the school I go to, and I don't think anyone on the faculty has experience with Norway (We have Japan, Germany, France, Lebanon, Austria and a couple of other countries represented in our faculty).

Thanks for the help I really appreciate it.

It used to be the case that one needed a visa to work for pay in Norway, even if you are being paid outside of the country, and regardless of the length of stay.