You showed up right as another poster, "GodisLove" was making the rounds here and it made you look suspicious... as in people were wondering if you were a sockpuppet of "GodisLove". We've been burned before and we don't like it. If you are not, in fact, "GodisLove", then no worries! If you are, then it's better to fess up now. Sockpuppetry is a bannable offense here at UF, but they might be willing to give you a pass the first time.
Next, regarding love...
(1) Love is an observable behavior. We observe love in several forms: mother/child bonding or father/child bonding, courtship/mating, and friendship/in-group cohesion. You may even want to go for why humans help strangers (philanthropy or altruism). There are studies for that, too. Which of these studies would you like to focus on?
(2) All behaviors have neural substrates. You should know this already. How? You should have been exposed to ablation studies in humans in combination with mammal/primate models. In short, there is no behavior that a human can perform if there is not a part of the brain to underpin it. Can you explain how you seem to lack this knowledge as a neuroscience studies graduate?
(3) Here's a basic article on reward systems in the brain:
I'll post more if I find more.
Let me just state that the neural substrates of love is an easily researchable topic on pubmed. If there are particular articles you want to discuss, let me know.