I’m sorry to hear about your deferral, but always remember that if you work hard, you can end up ahead at any school. Quite honestly, a deferral from Dartmouth is essentially a rejection. BUT you never know, especially if you are improving your application between now and the regular decision cycle.
Have you looked into the more prestigious liberal arts colleges? Amherst, Colgate etc are all great colleges. I’m not sure if they have neuroscience though, so make sure you check before you apply.
You may also want to consider Wash U, a lot of Dartmouth applicants also apply there too.
Best of luck!