Novel object recognition (NOR), and cued/contextual fear conditioning (CFC) are two good behavioural tests that are great for mice and rats - they may also work for hamsters. Just a note that NOR typically needs fairly large big N's per group, around 20, because it depends greatly on how mobile/motivated your animals are, how interesting are the objects you use, etc. I've seen studies pairing the conventional novel object test with different odours or food pellets to help motivate animals more, but haven't tried that myself.

 thanks