What Happens in Your Brain When You Fall in Love?

Love is that famous four-letter word that has inspired countless songs and sonnets. But what is it about this powerful emotion that makes our hearts thump, minds race, and palms sweat? 

"Love is a powerful feeling, and it is often a little different depending on what a person is giving to or receiving from the person who they love," says Heidi Moawad, MD, an associate editor of Neurology and Clinical Assistant Professor at Case Western Reserve University.

"For example, maternal love is often protective. And romantic love will eventually also become protective as people grow closer to each other and learn each other's vulnerabilities, but it doesn't usually start out that way."

Falling in love can be a thrilling, emotional experience, but what exactly is happening in your brain when you fall in love? It can feel like your brain has switched to vacation mode without telling the rest of you. Suddenly, logic and rationality seem to fly out the window, and you're left with a head full of romantic notions straight out of a Disney movie or 90's rom-com. 

Those feelings are all part of the neuroscience of love. The chemicals that flood your brain can make you feel like you're on top of the world.

Brain Regions Involved in Love

No matter what the poets say, love doesn't actually come from the heart. Of course, writing verses about what's happening in the depths of the ventral tegmental area sounds a bit less lyrical.

For starters, it isn't a singular emotion. It’s made up of many different elements and emotions, including physical attraction, romance, and affection. What exactly is love, then? It’s been the question posed by countless philosophers, poets, and songwriters–so it only makes sense that scientists would also take a crack at answering it.

Perhaps not surprisingly, there are actually many different theories about what constitutes love, but one popular model suggests that it involves lust, attraction, and attachment. According to researchers, each element involves a different system in the brain.

"Each of these drives are mediated by different brain regions—so the frontal lobe is involved in the prosocial aspects of romantic love, and the ventral tegmental area is involved in the reward feeling of attraction and getting positive feedback that someone who you are attracted to also likes you," Moawad says.

Brain Regions Involved in Lust and Passion

Feelings of lust stem from the brain's hypothalamus. This small, almond-sized structure, positioned just above the brainstem, is connected to basic needs and desires like thirst and hunger. It also controls automatic internal processes such as body temperature, blood pressure, and sleep cycle. 

And it's one part of your brain that helps regulate your sex drive. It triggers the release of hormones that increase sexual desire.

Brain Regions Involved in Attraction and Romance

When it comes to attraction and romance, two specific areas of the brain play a key role: the ventral tegmental area and the nucleus accumbens. Both areas of the brain play an essential part in the brain's reward system. This system floods the body with dopamine, a neurotransmitter that produces feelings of euphoria and pleasure. 

That's why the early stages of love can feel so thrilling and, at times, even addictive. It's normal to feel like you can't stop thinking about the other person and want to be with them all the time. 

Brain Regions Involved in Attachment

But love is about more than attraction and romance—it also involves attachment, affection, and commitment, which is, interestingly, also heavily influenced by the hypothalamus.

That’s because this area of the brain secretes chemicals that play a role in fostering trust and emotional bonds. 

Other Brain Regions Involved in Love

Other areas of the brain are also involved in our experience of love—makes sense so much of the brain is, it's such a big feeling! The amygdala, for example, helps to process the emotions that we experience. This is important because it creates the powerful associations we develop during the earliest stages of romantic relationships.

When you fall for someone, this region of the brain tends to slow down. This might explain why we sometimes ignore red flags and make poor judgments, particularly during those love-struck early days of a romance.

Neurotransmitters: The Chemical Messengers of Love

The early stages of love often feel like a whirlwind of emotion. We see everything through rose-colored glasses (which is why we don't see the red flags) and the euphoric feeling overrides everything else—but there's an important reason why. 

When you fall in love, the emotion triggers the release of chemicals such as oxytocin, vasopressin, and dopamine. Certain chemicals are associated with different stages of falling in love.

Testosterone and Estrogen Fuel Lust

We often wonder at the start of a relationship: Is it love, or just lust? This takes a little extra time to figure out, but lust is still present when you're truly in love.

Lust involves a desire for sexual pleasure and gratification. There is an evolutionary basis for our need to reproduce, which is why, like our other basic needs, the hypothalamus is heavily involved in this aspect of falling in love. 

The hypothalamus stimulates the testes and ovaries to release the sex hormones testosterone and estrogen. Both play a role in fueling feelings of passion and lust.

Dopamine, Norepinephrine, and Serotonin Reward Love

Attraction is connected to the brain's reward system, which involves the brain chemicals dopamine, norepinephrine, and serotonin. Dopamine is the "feel-good" hormone because it makes us experience feelings of pleasure. Norepinephrine is also released, which causes us to feel euphoric, and contributes to the ways we can feel giddy and excited during the early stages of love. However, this neurochemical can also fuel feelings of anxiety.

While the brain is experiencing an influx of these so-called "love chemicals," there is also a drop in an important neurotransmitter called serotonin. You're probably familiar with serotonin's role in mood—but it is also connected to intrusive and anxious thoughts.

Low levels of serotonin chemical have been linked to increased anxiety and obsessive-compulsive disorder.

Oxytocin and Vasopressin Promote Bonding

As relationships progress, the giddy excitement of early love is tempered by a deeper and more intimate commitment. This is influenced by a shift in the chemicals that are released in your brain. Dopamine and norepinephrine begin to drop, and two other hormones take center stage: oxytocin and vasopressin.

• Oxytocin is produced by the brain's hypothalamus, and it is sometimes referred to as the "cuddle hormone." It is released during sex, childbirth, and breastfeeding and helps promote bonding and emotional connection.
• Vasopressin is also believed to play an important role in social bonding. It is believed to promote attachment and protective behaviors.

"Romantic love is also often dependent on prosocial mental processes—which involves whether a person thinks that having a romantic relationship with a specific person will be accepted or admired within their social circle," Moawad says.

As relationships progress, these prosocial processes become increasingly important in our experience of love.

Some research suggests that it is the interaction between vasopressin and oxytocin that helps maintain romantic love, which is why it is so important for long-term relationships.

Emotional and Behavioral Changes: The Impact of Love

Falling in love can feel like a roller coaster of emotion as you careen through thrilling highs and unexpected twists and turns. Not everyone experiences the same emotional or behavioral changes when they catch feelings for someone, but common experiences include:

• Happiness and euphoria: The early stages of love can be one of life's peak experiences. It can be a time of intense euphoria and happiness.  
• Intense feelings: Your emotions might feel more intense and deeper than ever before. This includes the positive ones, such as love and lust, but also the negative ones, such as anxiety or jealousy.
• Changes in priorities: We often experience a shift in our priorities and commitments, particularly during the early stages of a relationship. This can help strengthen your connection to your new partner, but it can sometimes happen at the expense of other people and responsibilities in your life.

While we often think of love in positive terms, it isn't always sunshine and roses. Love can sometimes have a darker side, including feelings of hurt, jealousy, irrationality, and other challenging emotions. 

The dopamine rush that makes us feel madly in love with someone can also leave us feeling despondent when we are apart.

As the saying goes, we are all fools in love, which we can partly blame on the decreased activity in areas of the brain connected to rational thought and self-awareness. 

Love's Lasting Legacy: Long-term Effects on the Brain and Relationships

The neurological changes in the brain when we fall in love aren't just a temporary effect. Experiencing love, particularly romantic love, can have powerful long-term effects on the brain. 

• Stronger bonding: The chemical changes we experience when we fall in love promote bonding, and those changes can help make the brain more attuned to the people who matter the most to us. 
• Improve responsiveness: We might also experience shifts in the neural pathways of the brain, rewiring some connections and strengthening others. Such changes can connect us more to the needs of those we love, and improve our ability to relate to them in the years to come.
• Increased satisfaction: The shifts in the brain's reward system mean that our relationships with those we love bring motivation and pleasure to our lives. This can help us to feel more satisfied in our long-term relationships.
• Better cognitive functioning: Love is also associated with improvements in certain cognitive functions such as memory.  
• Greater stress resilience: It helps people cope more effectively with stress, fostering greater resilience in the face of life's challenges.

Every relationship is different, and your own experience with love may vary depending on the nature and quality of your relationship. However, healthy, long-term relationships have been shown to have a wide range of positive health effects.

The Bigger Picture of Love and Neuroscience

It might not sound particularly romantic, but it's your neurotransmitters, hormones, and hypothalamus (along with other regions of your brain) that lie at the heart of every love story.

Dopamine–that "feel good" hormone that causes feelings of euphoria and pleasure–is undeniably the star of the show, but love isn't a one-act play. Other chemicals play a part, too, including oxytocin, serotonin, estrogen, and testosterone.

It's also important to recognize that while love can come in different forms, research also shows that these forms of love may share underlying neurobiological mechanisms. For example, one study found that maternal and passionate love both increase activity in the ventral tegmental area.

When we fall for someone, key brain regions light up like a busy city skyline at night. The ventral tegmental area floods the brain with dopamine. The brain’s reward system kicks into overdrive, processing these rewarding sensations and linking the rush of passion with other complex emotions like attachment and empathy. It's why you might feel addicted to that special person you can't stop thinking about. 

While love doesn't actually come from the heart, you can take solace in knowing that your love story is written in the chemistry and function of something far more complex–your brain.