A dozen brain regions, working together, create feelings of passionate love. Stephanie Ortigue of Syracuse University and her colleagues worldwide compared MRI studies of people who indicated they were either in love or were experiencing maternal or unconditional love. The comparison revealed a "passion network"—the red regions shown here at various angles. The network releases neurotransmitters and other chemicals in the brain and blood that create the sensations of attraction, arousal, pleasure…and obsession.

For more details on how the network affects cognitive functions, see "Graphic Science: Your Brain in Love" in the February 2011 issue of Scientific American.

Graphic by James W. Lewis, West Virginia University