"Love and mental illness have some things in common: Well, love and obssessive-compulsive disorder (OCD) could have a similar chemical profile. One study showed that people in love and people with OCD both had low levels of serotonin, an important neurotransmitter."
(Originally posted in AOL Research & Learn)
SOURCES:
Slater, Lauren. "So What, Really, Is This Thing Called Love." National Geographic Magazine. February 2006. National Geographic Society.
http://www7.nationalgeographic.com/ngm/0602/feature2/index.html "What's Sexy?"National Geographic Channel. Airs Feb. 13 and 19, 2006. National Geographic Society.