I'm stuck on a paper topic. Any help would be appreciated!

Hey,

I'm in a neuroscience class which focuses heavily on the cellular aspect of systems neuroscience. I've been assigned to write a paper on a topic of my choosing- ack! I'm terrible at those. The brain is capable of so many fascinating things, but the scientific community knows so few definite facts that it's difficult to write a detailed and accurate physiologically based paper on many of the 'basic' psychological phenomena we take for granted.

My assignment is as follows: "The subject of the second paper will be open. You can write on a sensory modality, learning, memory, sleep, etc. The crucial condition is that it be based on the description of the neuronal mechanisms underlying the phenomenon (or process) that you are writing on. For example, if you want to write about sleep, we expect to see ionic mechanisms involved, neuromodulatory mechanisms involved, structures and how they work to generate the sleeping behavior. We don't want to see a long list of structures involved without any relationship to function."

What possible topics could I pick from? In class, we went over the topics of the perceptions of pain, sight, and hearing. We don't need to cover sensory modalities, but that's probably what would be easiest. I doubt that it's possible to write an accurate paper on the ionic and neuromodulatory structures involved in, for example, memory at this point in time.

Does anyone have any suggestions? What topics in neuroscience are fit for this kind of assignment? They specifically said they don't want fMRI based papers, as they are too general for their purposes.

Thanks so much for any help! I am absolutely not asking r/neuro to write my paper for me... I just need a nudge in the right direction!

edit: I ultimately decided to write on the communication between the gut's neurons and the central nervous system. More information here: http://www.nature.com/nrn/journal/v12/n8/full/nrn3071.html