For example, unconditional love, such as that between a mother and a child, is sparked by the common and different brain areas, including the middle of the brain. Passionate love is sparked by the reward part of the brain, and also associative cognitive brain areas that have higher-order cognitive functions, such as body image.
Ortigue also said (or at least the article about her study said) that falling in love takes one fifth of a second. That part of the article didn't make a lot of sense to me, but perhaps Neatoramanauts more literate in biochemistry can explain.
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