Originally posted by dr barb
I'm also interested in NS and was wondering what publications are preferred. Basic science research, clinical research, review articles, and/or a combination thereof?
Basic science publications are definetly more difficult and usually take longer to obtain results for publication than do clinical publications, and as such, basic science pubs look more impressive. That being said, there are quite a few medical researchers who only undertake and publish clinical papers. If you're going to do clinical research make sure that it is of high quality and well-designed, not just some retrospective chart review that any undergrad/med student can do in a few weeks during their summer break. Review articles don't carry much weight since they technically are not research, but rather like writing an essay for class where you just read what has already been researched by others on a topic and write about it. Although if you don't have time and are in a rush to get a pub on your CV then a review article may be the only thing you can do since generating data for a solid basic science or clinical paper takes time. Also if you write most of the review then you'll most likely be 1st author. Case reports are another quick way to get published, but once again don't look very impressive since you're not actually researching anything but rather reporting on an interesting or rare case that came up by chance. You could ask the neurosurgery attendings or residents at your school if they have recently come across an unusual case or rare disease they operated on and see if they'd be interested in writing it up with you.
And about how many publications should I strive for by the time I apply?
It's really hard to quote a specific number as the # of pubs by med students *during medical school* varies widely. Most publish absolutely nothing while in med school (even if they were involved in research), whereas others have multiple pubs by the time they graduate.
If you are really eager and persistent, you could have a bunch of case reports by the time you apply if you start early enough.
Review articles take longer to write since you have to go over the literature and write what is essentially a long essay. And most reputable journals won't publish review articles unless they are of high quality and sometimes only if they are written by leaders in the particular area of research (e.g. why would experienced researchers in the field want to listen to anything a mere medical student would have to say about the subject?). That is why most high-quality journals only *invite* well-known researchers to write review articles for their journal. But there are journals out there that will consider review articles from even medical students.
Depending on a little bit of luck, timing, and persistence you can put out a couple of basic science and/or clinical papers by the time you apply if you start early and pick projects that will give you publishable results in a timely manner.
And if I was really considering anything else, well, I surely wouldn't let the attending know 
