Love is in the air this time of year. It makes some people swoon, others cringe, and many crazy. Love is all around us – from romantic partners, to children, to friends, to pets, to favorite foods – but what do we really know about how or why we love the way we do?

The study of love is moving from a subjective theme of psychiatrists to an objective issue of neuroscientists; many areas, facilities, and circuits in the brain are now believed to be involved in the emotions and actions that compose our love of others.

The biology of love originates in the primitive parts of the brain, which evolved long before the more complex cerebral cortex. Additionally, scientists have uncovered potential roles of many chemicals, including oxytocin, vasopressin, dopamine, serotonin, cortisol, nerve growth factor, and testosterone, in pair-bonding and relationships. Such neurotransmitters and related pathways increase social recognition, motivation, reward, and overall health and decrease fear, anxiety, and stress. These findings support love as an evolutionary process that is necessary for survival. Interestingly, the brain activity in hate and negative emotions is distinct and different from the patterns of brain activity in love.

Still, studies of love are limited and subject to selection bias and cultural differences in love and affection and definitive proof of the scientific basis of love is lacking. Differences in types of love and lengths of relationships compound the challenge of defining mechanisms of love. For example, maternal love and romantic love are different emotions and probably involve different biological and chemical mechanisms.

A larger question may be, “Which came first? Love or biology?” Is the brain activity observed by neuroscientists the cause of our feelings of love or do our feelings of love cause our brain to react in certain ways? But, more so, what do we gain from defining the chemistry or biology of love, attachment, and affection? One argument supporting such research is that, by understanding the phenomena of love and attachment, we can better treat emotional and attachment disorders, possibly even with pharmacotherapy. Beyond that, scientific definitions, while interesting in our understanding of just how magnificent and amazing the brain is, may falsely simplify a complex and complicated experience like love.

In this season of love, it is possible that some things are better left unexplained. Love may be a mystery that we will never define. But we can certainly let love define us.

References

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