As the season of love approaches and comes to a close, it begs the question: How can something as powerful as love between two individuals even occur? Well, in reality, it’s a combination of social factors, psychology, chemicals, neurotransmitters, and hormones.
There are three main stages of love: the first stage is desire, driven by testosterone and/or estrogen; the second stage is the “love-struck” phase, characterized by high dopamine/norepinephrine and low serotonin; and the third stage is attachment, which includes the hormones oxytocin and vasopressin, which foster bonding.
The first stage of love, desire, or lust, is, as aforementioned, driven by testosterone and estrogen. These sex hormones are regulated by the hypothalamus, a region deep in the brain that helps control basic drives like hunger, thirst, and sexual behavior. At this stage, attraction is primarily physical, as during this stage, the brain is mostly focused on survival and reproduction, which is why this stage typically motivates individuals to seek potential partners.
The second stage of love, called attraction or “the love-struck” phase, is often referred to as limerence, or infatuation. This is obsessive and intense. Key chemicals released during this stage are dopamine, norepinephrine, and low serotonin. Dopamine controls rewards and happiness. Norepinephrine controls alertness and excitement. Interestingly, low serotonin is linked to obsessive thinking. At this stage, you feel euphoric, cortisol can rise, and sleep and appetite may decrease. You also may idealize this person and overlook flaws. Serotonin levels drop during early love, which is a pattern similar to patterns observed in Obsessive Compulsive Disorder (OCD), which explains intrusive thoughts about the individual.
The third and final stage of love is attachment, or long-term bonding. Key hormones here are oxytocin and vasopressin. Oxytocin is the infamous bonding hormone, and vasopressin is associated with protection and pair bonding. Oxytocin is released during physical touch, which is why at this stage, emotional intimacy occurs and trust and stability increase.
The brain ties all these together because it activates the brain’s reward circuitry, particularly dopamine pathways. Being near a loved one can trigger pleasure and motivation, reinforcing the bond. Over time, the attachment chemicals strengthen, and so does bonding.
Some interesting facts about love are that not only does the cocktail of chemicals and neurotransmitters have to be released, but social factors also play in. According to Psychology Today, a potential union that satisfies general social norms can contribute to people falling in love. This means that if it is more socially acceptable for you to be with your chosen partner, that can increase attraction.
Other factors determine “compatibility.” This includes similarity, propinquity, desirable characteristics, and reciprocal liking. Similarity means similar beliefs, personality traits, and thought processes. Propinquity refers to the familiarity that results from spending time together. Desirable characteristics include physical attractiveness and a desirable personality. And finally, reciprocal liking, which, interestingly, if one person likes you, then that can increase your attraction.
In conclusion, love is more than just an emotion. It is a biological attraction that goes back as far as humanity has existed. The science of love reveals that everything goes back to biology.
