Remember, much of what specialty people go into is self selective. I'm sure many folks could get into neurosurgery if they so desired, but go into other fields. As well as doing what you like, interests you, etc etc, what specialty you go into is in part dependent on the experiences that you have with members of that specialty. You might be interested in a specialty, but if you are constantly having negative experiences while rounding or have clashes with the attendings/residents, it is very likely that these things are going to have an affect on your desire and enthusiasm for that specialty. The reverse is also true. Without a doubt, Columbia has a very influential neurosurgery department. It is one of the best, and many of the attendings/residents provide some of the best experiences to medical students. Dr. Quest, for example, is quite a well known guy, but also is one of the advisory deans, a prolific adcom member, and plays trombone in a number of P&S events. He is quite possibly the most beloved advisory dean at the school, if my experiences with people in his group are a good representation. In addition, the neurosurgery department has sent in more residents/attendings/fellows than any other department for anatomy labs. They are great teachers and very enthusiastic. Good experiences with mentors is a powerful way to kindle an interest. You then combine this with the fact it is a huge department (NYP has 32 attendings!!!!) and a very approachable group of neurosurgery researchers looking for medical students wanting semester and summer research. There is also the fact that there are some students (a minority, but some), who were attracted to Columbia because of the strength of their neurology/neurosurgery/psych departments. All of these factors come together to (in my opinion) explain why Columbia has such a powerful presence in this field.