What is Love, Exactly? Let Neurobiology Explain

by Dov Michaeli, MD, PhD of The Doctor Weighs In

(Originally posted on The Doctor Weighs In)

Valentine’s Day is once again upon us and the subject of love fills the pages of newspapers, magazines, and television screens — all too often by marketers hawking their wares. Who hasn’t seen the ad of the guy who bought his girlfriend a giant teddy bear only to have her cuddling with it instead of him!

But, I digress. What I want to write about is a story by Tara Parker-Pope that appeared in the Wall Street Journal some time ago, but has remained in my thoughts ever since. Titled, “Is It Love or Mental Illness? They’re Closer Than You Think,” it described an interesting study comparing the brain scans of people who had recently fallen madly in love with another group that had been scorned by the ones they adored.

The limbic system, nucleus accumbens, and all that jazz

A system of neurons, called the limbic system, and a group of neurons, called the nucleus accumbens, are the areas of the brain that are responsible for feelings of satisfaction, reward and pleasure. They communicate with each other using the neurotransmitter dopamine. Unfortunately, the neurons in the nucleus accumbens can take matters too far and initial pleasure can develop into an addiction. Who said there is no such thing as too much of a good thing?

So, what is love (neurobiologically speaking)?

In the study, Dr. Helen Fisher, an anthropologist at Rutgers university, examined the brain MRIs of both groups of people. When the folks that had recently fallen in love were shown a ‘neutral’ picture of acquaintances or colleagues — nothing much happened (in the MRI scanner, that is). But, when they were shown pictures of the loved one(s), their limbic system and the nucleus accumbens lit up — the same system of neurons associated with pleasure and addiction.

When the scorned people were shown pictures of their former lovers, their dopamine- mediated neurons lit up, just like the ‘happily in love’ group. But, the amygdala, a system associated with anger and obsessive compulsive behavior, also lit up. Moreover, the prefrontal lobe, the area where all these feeling are supposed to be integrated and controlled, worked overtime. In fact, in some extreme cases the flood of negative feelings from the amygdala overwhelmed the capacity of the prefrontal lobe to exert some calming influence on the emotional storm. This scenario gives a new meaning to the phrase “hell hath no fury…”.

My clinical assessment

For all of you lovelorns, your love is not that much different from a temporary addiction. And, you spurned ones — an overwhelmed prefrontal lobe is no defense in court.

Happy Valentine’s Day!