system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What in the brain differentiates between romantic love and platonic love?

What in the brain actually causes the different feelings? I'm not asking how one's feelings differentiate, only their brain—so a scientific *reason*. How does the brain respond differently and cause different chemicals to be produced or whatnot?
gpt
The short of it is, when something excites your brain, there is an increased frequency of charge distributions that occur over the neuron. The more exciting something is, the higher frequency (more often) the charges zip back and forth, telling the neuron to release the happy neurochemicals. It is not equal, because your Amgdala and Hippocampus perceive simulations as requiring a different amount of each neurochemical. If you romantically love someone, you have a high frequency of complementary neurochemicals (dopamine, oxytocin, and vasopressin), operating when your central nervous system is excited from your perception. Contrasting this with plantonic love, you will simply have a decreased amount of activity, and much much less vasopressin. The amount of interactions to successfully trigger the next response (temporal/spatial summation) will be lower, and so the signal doesn't travel as vigorously. This leads to A) the message not completing a "full circuit" and B) a decreased overall volume of chemicals. 

Hope that helped.