The Chemistry Between Us: Love, Sex, and the Science of Attraction

by Larry Young

There’s a lot of indirect evidence to support the love-as-addiction scenario. Lovers, for example, can act like painkilling drugs for each other. In one test, fifteen people who were nine months into new relationships—long enough to be in love, but not so long as to have grown sick of each other—were placed in fMRI machines and subjected to varying degrees of pain caused by heat. They looked at pictures of attractive acquaintances, their partners, and words that were previously shown to reduce pain. The words did reduce the amount of pain the people said they were feeling, but imaging revealed that the reduction was due to simple distraction: the words took their minds off it. Pictures of acquaintances had no effect on pain. But pictures of their lovers reduced pain by activating the reward system, including the accumbens, amygdala, and prefrontal cortex, just like drugs of abuse do. The addiction model also explains the allure of the long-distance relationship. It’s really just extended foreplay. When appetitive reward is won only intermittently, explains Jim Pfaus, “not only do you not get tolerant, you are actually more sensitized to it. Sex works the same way, and that’s how long-distance relationships work. It’s dramatic, right? ‘We’ll see each other every two weeks.’ And then you anticipate, and for two days before you see each other, you are full of anticipation for the reward, and then engaging in that appetitive response, as well as hot sex, well, that glues those...