|Anterior Cingulate Cortex|
Two primary forms of romantic love have been studied scientifically; Passionate (face-to-face, ignore-the-world) and Companionate (side-by-side, face-the-world–together). Passionate love blooms rapidly but fades within 24-36 months. The evolutionary theory behind this is that brain chemistry evolved to allow male-female attachment to last at least long enough to rear a a single child together. ** The main hormones involved in love are dopamine, oxytocin (touch hormone), and phenylethylamine (love hormone). High vasopressin levels in male prairie voles keep them monogamous for life. It hasn’t been substantiated yet whether this is the case with humans. Phenylethylamine is a potent chemical which is addictive because it binds to dopamine receptors in the brain. That is why romantic break-ups result in emotional withdrawal symptoms such as depression, inability to concentrate, social isolation, and restlessness.
Recent studies using funtional magnetic resonance imaging (fMRI) scans have shown that two areas of the brain become active when test subjects who self-identified as ‘being in love” were shown photographs of their beloved. These areas are the anterior cingulate cortex and the insular cortex (see diagram).
Insular within the cerebral cortex. Labeled on upper right.
**Robbins, T. W., and B. J. Everitt. 1996. Neurobehavioural mechanisms of reward and motivation. Current Opinion in Neurobiology 6:228-68
Sources: Fisher, Helen, Why We Love: The Nature and Chemistry of Romantic Love, Henry Holt and Company, New York, 2004
Crenshaw, Theresa L., The Alchemy of Love and Lust: How Our Sex Hormones Influence Our Relationships, Pocket Books, New York, 1996
Oxytocin – The touch hormone
Phenylethylamine - The Love Hormone (very addictive, handle with care)
Chemical structure of the argipressin. The above structure is a compound from the vasopressin family with an arginine at the 8th amino acid position. (wikipedia)