Helen Fisher, in her 2004 book, Why We Love: The Nature and Chemistry of Romantic Love, argues that it is the latter. Fisher is an anthropologist who has researched the evolutionary biology behind love (both human and animal) and makes a strong case that passionate, romantic love is an altered state, with associated brain chemistry changes and a specific evolutionary goal.

According to her, passionate love seems to be a universal human “brain system” and exists world-wide and through history.

It is one of the three brain systems that have evolved in human beings to insure the perpetuation of the species: lust, romantic love, and deep attachment. The first drive is designed to stimulate the wish to procreate, the second to focus the drive on a particular partner, and the third to ensure the couple will stay together long enough to promote the survival of a child. Fisher sees romantic love as more powerful even than the sex drive, but it is an essential drive not an emotion.

The physical sensations of being in love seem all to be universal: feeling swept away, the brain racing, “butterflies in the stomach,” surges of energy, euphoria, acute awareness, a sense of heightened prowess, sexual desire. Interestingly, these symptoms sound like those described on Wikipedia for a cocaine high: increased “alertness, feelings of well-being and euphoria, energy and motor activity, feelings of competence and sexuality.” Fisher looked for brain chemicals associated with these symptoms and evolved a hypothesis that heightened levels of dopamine and norepinephrine and decreased levels of serotonin play “a role in human romantic passion.”

In support of the evolutionary underpinnings of romantic love, Fisher argues that animals display many of the human components of falling in love: “heightened energy, focussed attention, euphoria, craving, persistence, possessiveness, and affection…” Furthermore, the brain chemistry seems to be the same.

Most intriguing is Fisher’s observation on the short-term nature of romantic passion and her hypothesis for its limited duration: “romantic love did not evolve to help us maintain a stable, enduring partnership. It evolved…to drive ancestral men and women to prefer, choose, and pursue specific partners, then start the mating process and remain sexually faithful to “him” or “her”  long enough to conceive a child.  After the child is born, however, parents need a new set of chemicals and brain networks to rear their infant as a team–the chemistry of attachment. As a result, feelings of attachment often dampen the ecstasy of romance, replacing it with a deep sense of union with a mate.”

Check out Helen Fisher’s TED talk.

topics: family