Love Is All in Your Head -- Or Is It in Your Genes?
Sabelli's research showed that high PEA levels help explain increased sex drive and activity in the manic phase of manic-depressive illness, while low PEA levels reflect loss of libido in depression. PEA is effective when given by mouth, but like Viagra, could be dangerous in patients with heart disease.
The final phase of love, the one that leads to diamond wedding anniversaries, is a calm, secure feeling of attachment to a long-term partner. "This is important to conserve our mating energy, bonding with only one partner at a time," Fisher says.
Oxytocin is the hormone thought to be responsible for this phase of love, as well as for mother-child bonding. Fallon calls it the "cuddling hormone," as it is released by touch "done with the right rhythm and pressure."
Could there be a genetic basis for long-term commitment? Perhaps at least in the prairie vole, an extraordinarily faithful rodent, explains Thomas Insel, MD, director of the Center for Behavioral Neuroscience at Emory University in Atlanta.
From their first mating, prairie voles bond for life. The male defends the female from all other males and mates with her to the exclusion of all other females. Even when their mate is removed from the colony, 80% of males refuse to mate with any other female.
Insel discovered that oxytocin and vasopressin, a nerve chemical linked to memory, are released in the rodent's brain at first mating. If Insel artificially changed the levels of these hormones, he could wipe out the lifetime bond.
Even more extraordinary, Insel found the gene responsible for this behavior and developed a mouse carrying this gene. He was hoping to create a "monogamouse" that would remain faithful to one mate, unlike most mice who mate with any available female. But, alas, the experiment was unsuccessful. "'Monogamouse' does not exist," Insel tells WebMD.
While Insel does not think his research might lead to any type of love potion, he hopes that it might eventually provide an approach to autism, a disorder in which children don't connect emotionally with people around them.
Fallon believes that science might eventually assist Cupid with just the right mix of nerve chemicals to intensify attraction, romantic excitement, and long-term bonding. But probably not any time soon.
"If we really understood the [science], we could increase or decrease the threshold for falling in love," Semir Zeki, PhD, tells WebMD. "A neurochemical to manipulate this emotion would be very heavily controlled, and not advisable to use," says Zeki, a professor of cognitive neurology at the University College of London in England.
By using functional MRI scans, Zeki studied brain activity associated with romantic love. Scans done while subjects were viewing pictures of their love interest were compared with scans done while they viewed pictures of platonic friends, and the scans were different.