So I think it is OK for sophomores to start gathering ideas, but at this point I would be thinking very broadly and not trying to narrow things too much–except as to budget.
I do not think it is too early to have a serious conversation with your parents about exactly what they are willing to pay for college (and I agree keeping in mind med school is very expensive is typically an important part of that conversation). Depending on your budget it may end up there are only a few good options for making that budget, or many, but that is important to know.
In terms of specific colleges, if UMass Amherst would be affordable for you and you do in fact end up with the grades you need a couple years from now, that may well be the obvious choice. And that is not at all a bad thing!
In terms of other publics, they may struggle to compete with UMass Amherst on cost.
But I will just toss out that a lot of premeds we know take a look at Pitt because it is a really nice school for premed–excellent related departments, and an extremely high density of experience opportunities in close proximity. And in fact they are particularly strong in Neuroscience. Not that these lists are definitive, but this gives you some idea:
They also have some merit available, although it may or may not be enough depending on budget. Subject to budget, though, it could be worth checking out.
Another public along the same lines you might want to consider would be Minnesota. Nice location in the Twin Cities which again makes it very convenient for experience opportunities, very strong related departments including Neuroscience, and they have merit (in fact their Net Price Calculator will tell you how much merit you will get).
In terms of private research universities, again this will very much depend on how your grades go. But one you might want to keep in mind is Case Western. Again, very good for premed academically and in terms of experience opportunities, excellent for Neuro, and has a robust merit program.
Finally, I would suggest you keep in mind the possibility of going to a Liberal Arts and Sciences college. There are many which have strong med school placement records, and many of those also have robust merit programs.
Way too many to mention, but to give you an idea, Rhodes College is popular in premed circles with a very robust merit program and a very popular Neuroscience major:
They also have a relatively low full cost of attendance, so it is possible Rhodes could actually be cost-competitive with UMass.
Again, all this is subject to budget, and your eventual grades. But I think exploring some of these various options, and maybe thinking ahead to some possible visits, is appropriate for a sophomore.