Love is an essential and inseparable part of our lives and has several complex biological mechanisms underlying it. A combination of neurotransmitters and hormones are involved in the chemistry of love. Let us find out how love works scientifically.
What is the Chemistry of Love in the Brain?
The chemicals 1 Young L. J. (2009). Being human: love: neuroscience reveals all. Nature, 457(7226), 148. https://doi.org/10.1038/457148a in our brain have a significant role to play when it comes to love. Evolutionarily, love can be understood as a means to reproduce and nurture for the survival of our species. To that end, a complex circuit of hormones, neuropeptides and neurotransmitters work together to enable this feeling.
Stages of Love
What triggers love in the brain?
Many scientists have studied the chemistry of love. Researcher Helen Fisher proposed three stages 2 Seshadri K. G. (2016). The neuroendocrinology of love. Indian journal of endocrinology and metabolism, 20(4), 558–563. https://doi.org/10.4103/2230-8210.183479 of love in a relationship, each one governed by a set of hormones and brain chemicals. They are as follows:
1. Lust
The initial stage in the chemistry of love is usually lust. The biological response of the body during this stage is somewhat contradictory to the succeeding stages. Lust underlies the need to unite and procreate with another person and develops due to our natural instinct to mate with a partner.
At this stage, the physiological mechanisms are akin to that of stress, which is often a trigger for proximity. The sympathetic nervous system plays a crucial role during this time along with the hypothalamo-pituitary-adrenal (HPA) axis.
A person feeling lust may experience a racing heart, fast breathing, and slight palpitations, which are symptoms similar to that of fear. Norepinephrine (also known as adrenaline) is the main neurotransmitter involved in this phase.
The reproductive hormones, testosterone and estrogen are also important at this stage.
2. Attraction
Attraction is associated with feelings of excitement and a need for connection. A 2000 study 3 Langlois, J. H., Kalakanis, L., Rubenstein, A. J., Larson, A., Hallam, M., & Smoot, M. (2000). Maxims or myths of beauty? A meta-analytic and theoretical review. Psychological bulletin, 126(3), 390–423. https://doi.org/10.1037/0033-2909.126.3.390 confirmed that not only was physical appearance important to humans but certain particular features seemed to appear attractive across individuals and cultures.
The brain chemicals that govern this stage are norepinephrine, dopamine, and phenylethylamine. Attraction in the chemistry of love is mainly governed by the hippocampus, hypothalamus, and anterior cingulate cortex of the brain. When activated, these regions can significantly reduce defensive behavior and increase trust towards a romantic partner.
Read More About Attraction Here
3. Attachment & Commitment
In this stage, the passion turns into attachment towards one’s significant other. The hormones responsible for this stage are oxytocin, vasopressin, and antidiuretic hormones. A 2004 study 4 Bartels, A., & Zeki, S. (2004). The neural correlates of maternal and romantic love. NeuroImage, 21(3), 1155–1166. https://doi.org/10.1016/j.neuroimage.2003.11.003 found that it activates the reward system of the brain resulting in a reduction in emotional judgment, fear, and depression and an enhancement of mood.
The attachment phase is also characterized by increased levels of dopamine in the brain. Oxytocin promotes bonding and trust that helps in the development of long term love and relationships. The intensity of love often fades but attachment continues to persist and helps you feel secure and safe.
Read More About Attachment Here
The Love Hormones
Let us explore the love and brain connection a little further. Which are the main characters in the chemistry of love?
Some of the chemicals for love in the brain are:
1. Norepinephrine
The production of adrenaline is governed by the neurotransmitter, norepinephrine 5 Nagatsu T. (2007). The catecholamine system in health and disease -Relation to tyrosine 3-monooxygenase and other catecholamine-synthesizing enzymes. Proceedings of the Japan Academy. Series B, Physical and biological sciences, 82(10), 388–415. https://doi.org/10.2183/pjab.82.388 . The adrenaline rush we experience while in love causes the racing heart, sweaty palms or flushed cheeks. A 2018 study 6 Mittal, R., Debs, L. H., Patel, A. P., Nguyen, D., Patel, K., O’Connor, G., Grati, M., Mittal, J., Yan, D., Eshraghi, A. A., Deo, S. K., Daunert, S., & Liu, X. Z. (2017). Neurotransmitters: The Critical Modulators Regulating Gut-Brain Axis. Journal of cellular physiology, 232(9), 2359–2372. https://doi.org/10.1002/jcp.25518 found that high levels of norepinephrine can lead to increased joy or loss of appetite. This hormone triggers euphoria and feelings of bliss, increased energy, lack of sleep or appetite, and focused attention on the person you are attracted to.
2. Dopamine
Dopamine (the happy hormone) is released in our brains when we feel good. Some other activities that stimulate the production of dopamine include eating, exercising, reading our favorite books. Dopamine has a significant effect on our brain processes that govern our emotional responses and our ability to express pleasure.
Our ability to be sociable is also closely tied with dopamine neurons. A 2013 study 7 National Collaborating Centre for Mental Health UK. (2013). SOCIAL ANXIETY DISORDER. Nih.gov; British Psychological Society. Available from: https://www.ncbi.nlm.nih.gov/books/NBK327674/ has shown that people with social anxiety have low dopamine levels. Dopamine activates the receptors of the brain associated with the pleasure system which increases the feelings of euphoria and enjoyment.
Read More About Dopamine Here
3. Phenylethylamine
Phenylethylamine is responsible for the butterflies in the stomach we feel when we are around our lovers. A 2014 study 8 Irsfeld, M., Spadafore, M., & Prüß, B. M. (2013). β-phenylethylamine, a small molecule with a large impact. WebmedCentral, 4(9), 4409. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3904499/ pointed out that our first attraction towards someone causes our brain to release high levels of Phenylethylamine. It is also responsible for the production of dopamine and endorphins. These are also responsible for making us feel euphoric and energized.
4. Oxytocin
Oxytocin, also known as the love hormone, is a neurotransmitter associated with empathy, trust, sex, and relationship building. Increased levels of oxytocin are released during cuddling and orgasms.
This neurotransmitter is produced in the hypothalamus. A 1997 study 9 Carter, C. S., & Altemus, M. (1997). Integrative functions of lactational hormones in social behavior and stress management. Annals of the New York Academy of Sciences, 807, 164–174. https://doi.org/10.1111/j.1749-6632.1997.tb51918.x found that an increase in oxytocin associated with birth and lactation might make it easier for a woman to be less anxious around her newborn and to experience and express loving feelings for her child.
5. Vasopressin
After the initial stages of passion and lust pass, some people may begin to experience a feeling of companionship and stability with their partners rather than a sense of excitement. This occurs due to an antidiuretic hormone called vasopressin.
This hormone creates the desire to bond and nurture your partner. A 2015 study 10 Zimmermann-Peruzatto, J. M., Lazzari, V. M., de Moura, A. C., Almeida, S., & Giovenardi, M. (2015). Examining the Role of Vasopressin in the Modulation of Parental and Sexual Behaviors. Frontiers in psychiatry, 6, 130. https://doi.org/10.3389/fpsyt.2015.00130 also found it to have strong effects on men because of how it interacts with the male sex hormone, testosterone.
Takeaway
While some believe that love is a complex combination of hormones and chemicals, others criticize the reduction of love to chemistry, highlighting other socio-environmental factors that may play an equal part. However its genesis may be, love plays a pivotal role in the life of a human and knowing the chemistry of love can help us understand our behavior better.
At a Glance
- Several neurotransmitters and hormones are involved in the chemistry of love.
- According to Helen Fisher, love can be distinguished in three different stages – lust, attraction and attachment.
- Each stage has its own set of brain chemicals playing their part in the chemistry of love.
- Some of the neurotransmitters involved in the chemistry of love include dopamine, norepinephrine, and serotonin. 5. The parts of the brain responsible for love include hippocampus, hypothalamus, amygdala, and other cortical and subcortical regions.
- The parts of the brain responsible for love include hippocampus, hypothalamus, amygdala, and other cortical and subcortical regions.