Completely disagree. OP didn't ask about neuro-related things as they pertain to medicine. S/he just asked about neuro-related activities. OP also stated that s/he will be shadowing a neurosurgeon, I don't think adcoms will infer that OP wants to be a neurosurgeon. Otherwise, we'd all have to shadow every single specialty to be prepared for med interviews... As far as "silly for you to be diving into neuro-related fields before you even start medical school" I think the worst advice you could give an aspiring physician or scientist is to tell them not to pursue their interest in a specific field. Since when did we decide that our pre-med generation should be a bunch of boring robots who do the same thing, rather than having a bit of eccentricity? I love neuroscience, I pursued it in a research lab before, during and after college, got publications out of it, taught it to middle school students, yet had plenty of shadowing/clinical experience outside of neuro. Let's not discourage people from being passionate about science. Third year med school will tell OP whether or not clinical neuro is for them.
In the meantime OP, if you're interested in medicine, try to balance the neuro experience with some clinical volunteering or other things that'll give you ammo in case anyone thinks you're an over-ambitious wannabe neurologist.