The subject of sexual attraction and love has long been an area of interest in the scientific community. Although many of us would like to believe that love is beyond explanation, past studies show that a person in love exhibits similar mental activity to a drug addict. People in love were also shown to have symptoms consistent with mental illness.
There are three stages to falling in love. The first is lust, when our hormones drive us to search for a partner. The second is attraction; in this stage, we are infatuated with our partner. We find ourselves thinking of them constantly, sometimes sacrificing food and sleep. Three chemicals play an important role in our behavior during this stage.
Norepinephrine, or adrenalin causes our hearts to beat faster as well as making us nervous and sweaty. Dopamine and serotonin are released, stimulating the pleasure center of our brain, and may drive us temporarily insane. Brain activity parallels what happens when a person uses cocaine. People in love where found to have 40% lower serotonin levels in their brains than those who were not. Similar serotonin levels can be found in people suffering from obsessive compulsive disorder.
If the relationship progresses beyond the second stage, it enters the final stage: attachment. In this stage we have made an emotional commitment to our partner, and are significantly more calm. Regular sex seems to be the key to releasing the hormones integral to developing a lasting bond. Oxytocin and vasopressin, released by both sexes upon orgasm, are key to long term commitment. Oxytocin, thought to promote social bonding, is also released during child birth and breast feeding. Vasopressin plays an important role in sexual motivation.
Scientists experimented with prairie voles, known for long-term pair bonding and having more sex than necessary to reproduce. When the male voles were dosed with a drug that suppresses vasopressin, they lost interest in their partner, no longer warding off other suitors.
These stages tend to be more intense for teenagers and those falling in love for the first time. Just as in addiction, we experience symptoms similar to withdrawal after a break-up.