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Book Summary: Wired for Love – A Neuroscientist’s Journey Through Romance, Loss, and the Essence of Human Connection

Wired for Love (2022) combines fascinating neuroscientific research with a captivating personal story to reveal some of the secrets behind that great human mystery: love. Love is often thought of as a topic best left to poets and musicians – but it can and should be studied as a legitimate scientific question. In a world that is constantly throwing up new challenges to romance, from online dating to global pandemics, an understanding of and respect for love is more important than ever before.


Psychology, Sex and Relationships, Biography and Memoir, Fitness and Dieting, Cognitive Neuroscience and Cognitive Neuropsychology, Science and Math, Science, Autobiography, Biology,  Sociology, Mental Health, Biography

Introduction: Fall in love with love from a scientific point of view.

In the United States today, half of adults are single, compared to 22 percent of adults in 1950. And according to Pew Research, half of those single adults say they’re not even on the dating market. More households than ever before include single parents – which means more loneliness. On top of that, the explosion of online dating apps has created an environment in which people are overwhelmed by choice and always on the lookout for a “better option.”

So, it seems like many people today are turning away from love. But we must remember that love isn’t optional. It’s an essential part of being human, a biological necessity, something that evolution has wired us to experience. And that’s exactly what you’ll learn about in this summary to Stephanie Cacioppo’s book Wired for Love.

[Book Summary] Wired for Love: A Neuroscientist's Journey Through Romance, Loss, and the Essence of Human Connection

In this summary, you’ll learn

  • about the surprising factors that drive attraction;
  • how you can decide between two romantic partners; and
  • why your brain panics when you lose the person you love.

Love blossoms inside the brain.

The language of love is all about the heart. We say: “You stole my heart,” or in the opposite case, “You broke my heart.”

But actually, these phrases would be much more accurate if we said “You stole my brain,” and “You broke my brain.” But that just sounds plain wrong! It transforms love from something deep and profound into something banal, grotesque even. And yet, it is the case that love starts, grows, flourishes, and ends in the brain.

So let’s start with the aspect of love that’s easiest to understand: attraction. Attraction is well understood by biologists. We know that it happens incredibly quickly – we can assess the suitability of a prospective mate within less than 200 milliseconds of first seeing them.

We also know many of the factors that drive attraction. And, as strange as it might sound, one of those things is ourselves. One study showed participants photographs of themselves photoshopped onto the bodies of the opposite gender. Both men and women failed to recognize themselves and rated their own photo as the most attractive of the bunch!

Another thing that plays a critical role in attraction is smell. We tend to be attracted to people who have scents that are different from our own. Why? Well, our scent is influenced by our immune system. And offspring produced with someone whose immune system is different will inherit more ways of fighting off disease.

So that’s the story of “love at first sight.” But what about what happens in our brains when we begin to fall in love deeply?

At that point, the brain begins releasing a cascade of neurotransmitters and chemicals. These have a major effect on our mood and the way we perceive the world. Falling in love triggers a region of the brain called the ventral tegmental area, which is – coincidentally – heart-shaped. This pumps dopamine into the brain and triggers the same regions that are activated when we eat delicious food or drink wine.

But that’s not where the story ends. Falling in love also increases the production of norepinephrine, which distorts our perception of time. This is what makes it feel as if time is flying, and that we’re laser-focused on every moment with our beloved. Simultaneously, serotonin levels drop, which might cause irregular eating patterns or obsessive thoughts about the person we’re in love with. Finally, physical contact with a lover triggers the release of oxytocin, the hormone that increases feelings of empathy and trust.

So, in short, there’s a lot going on when we fall in love! But what exactly is the point of all this? Is love just about helping us identify and pair with a mate? Or is there something more going on? Let’s explore this topic further.

Love makes us sharper, more creative thinkers.

At one point, you could see flyers all over the school library in Dartmouth College, New Hampshire. If you came closer, you could see they read, Wanted: Women in Love.

Turns out, these flyers were bait. Stephanie, the author of the flyers, and also, the author of the book, would get knocks on her door during office hours from female students with particular requests.

The flyers were informing the students about the author’s research and invited them to come to try out her “Love Machine.” The true name for the test that she’d developed was “System and Method for Detecting a Specific Cognitive-Emotional State in a Subject.” So you can see why the students preferred to call it the Love Machine. The test was pretty simple – a ten-minute computer-based assessment that students believed could help them decide between two potential romantic partners.

And so, one day, a student came in with a dilemma – a dilemma similar to those of many others. Should she choose the popular, good-looking guy – let’s call him Blake – or the geek with the cute smile – Shiloh?

Stephanie agreed to run the test for her, and it worked like this: The screen flashed the name of her first potential partner, Blake, for 26 milliseconds. That was long enough for the test-taker to see the name but not long enough for her to consciously perceive that she’d seen it. It transmitted a subliminal message to her brain and triggered whatever emotions were associated with Blake.

Then, the participant was asked to complete a series of lexical tasks. These involved sorting out real words from fake ones. When the student was primed with the name of Blake, she recognized the real words almost 20 percent faster than when primed with the name of her second option, Shiloh.

But what if this didn’t mean that the participant actually preferred Blake? What if maybe she was so distracted by her feelings for Shiloh that it made her perform worse on the lexical task? To test this, Stephanie conducted a separate Love Machine experiment on women who declared that they were madly in love with their partners.

In this case, she put the names of the women’s partners into the Love Machine along with the names of friends they’d known for the same amount of time. The result was that people performed significantly better after being primed with the name of their beloved partner rather than their friend.

But, why was that the case? Why would love improve the rapidity with which a person’s brain could read? The author guessed that it was related to the way the brain is interconnected. When Blake’s name flashed in front of the screen, it excited the neurons, sent out dopamine, and stimulated the connections between different areas of the student’s brain. She didn’t make a conscious decision for any of this to happen – instead, the test revealed her unconscious preference for Blake over Shiloh.

⁠It also triggered more recently evolved, sophisticated areas of the brain, not just the classic dopamine-hungry reward system. One of these areas was the angular gyrus – an area that evolved in our brains only very recently along with uniquely human traits like creativity, intuition, autobiographical memory, complex language, and imagination. We don’t readily associate these things with being part of the primitive “emotional” brain! But love, as it turns out, plays a highly complex role and completely changes our way of thinking. It enhances creative performance, it helps us tackle intellectual challenges, and it even makes us better at assessing the mental states of strangers.

It’s also good for our bodies. People in satisfying, healthy long-term relationships have better sleep and immune functions, they exhibit fewer addictive behaviors, and experience fewer strokes.

And what’s best of all, love works the same for everyone regardless of whether you’re a man or a woman, gay, straight, or trans. When you’re in love with someone, your brain lights up in the same way as everyone else – making it a universal phenomenon, hardwired into human nature.

Human brains are wired to connect with other brains.

Imagine this. You’re at a work conference, and just before the presentations kick off, the person next to you says: “If I start snoring, punch me.”

These were John Cacioppo’s first words to Stephanie, who would go on to become his wife. She spotted a professor nearby who was slumped in a chair and said: “He’s snoring. Do you want me to punch him, too?”

John introduced himself, although he didn’t need to – Stephanie knew exactly who he was. They were at a neuroscience conference and John was renowned for his work on the neurobiology of loneliness. What she hadn’t expected was that he would be so handsome in real life, with his olive skin, dusky gray hair, and broad smile.

Though it had been a long day at the conference, John and Stephanie talked for three hours straight, late into the night. By the end, they were finishing each other’s sentences, and they couldn’t stop saying “Me, too!” and “I know.” If the two of them had been hooked up to EEG machines, they’d have seen their brain waves synchronizing. Neurologically and biologically, they were already falling for one another. John – known as “Dr. Loneliness” – plus Stephanie – known as “Doctor Love.” It seemed like a match made in heaven.

So what made their attraction so strong? One of the factors was their alikeness – ⁠the amount of common ground they were able to find between themselves.

Alikeness is related to shared hobbies and interests. But it’s also about physical movement. Various studies have shown that when people are made to play a mirror game, where they copy each other’s movements, they find each other much more attractive than otherwise.

On a biological level, when people recognize a sense of shared identity, they feel significant to one another. As a result, their brain’s mirror neuron system, or MNS, begins to activate. This is the part of the brain that lights up when we act and when we see someone else performing the same action. You know how, sometimes, when you see someone else laughing and you can’t help but crack up yourself – even if you don’t know what the joke was? Well, that’s the MNS at work.

It gets even more fascinating. Mirror neurons don’t just mirror the actions of others – they actually seem to sense the intent and motivation behind the actions as well. The author conducted a test in collaboration with neuroscientist Dr. Scott Grafton, with the famous Dr. Rizzolatti as a test subject. They hooked his head up to a machine and monitored his brain activity while he looked at pictures of people grasping objects – like a cup of coffee – and moving with different intentions – like to drink it or not to drink it. The result? The human mirror neuron system was capable of understanding the intentions of other people subconsciously in as little time as it takes to blink an eye.

So, could it be that mirror neurons are behind it all? After all, the more you feel like you and your partner are one, the more likely it is that your relationship will last.

Love and lust feed off of one another.

In the 1960s, psychologist Dorothy Tennov was curious about what people thought about love and lust – specifically, can one exist without the other? So, she surveyed 500 individuals on their romantic preferences. Fifty-three percent of the women and 79 percent of the men agreed with the statement that they’d been attracted to people without feeling “the slightest trace of love.” Meanwhile, 61 percent of the women and 35 percent of the men agreed with the statement that they could be in love without feeling any physical desire.

The results suggest that love and lust are fairly separable. But on a neurobiological level, the line between the two is much blurrier. Think of a person you find extremely physically attractive. You might feel as if the sensations you’re experiencing are purely physical, like the tingling and so on⁠. But touching and kissing, whether they’re real or imagined, release the same neurochemicals – like dopamine and oxytocin – that flood your body when you’re in love. This, by the way, is why many “friends with benefits” end up growing emotionally attached to each other.

Now, we often speak about lust as something that belongs to the “animal brain” – the primitive regions of our brains we have in common with many other primates. But current neuroscientific research suggests that one unified brain network may be equally responsible for both love and lust. And it includes not just basic mating areas of the brain but also uniquely human ones.

In one study, Stephanie scanned the brains of 29 young women who had previously scored high on a passionate love scale. The more they self-reported feeling emotionally close to their partners, the more likely they were to say they were physically satisfied with their partners. The area of the brain that was most activated in these women’s brains was one called the insula.

The insula plays a key role in self-awareness. It helps us understand the things we’re craving at a given moment – be it a sandwich, a massage, or a piece of music.

But physical desire doesn’t light up the whole insula – just a specific, isolated part toward the back of this brain region. At the same time, feelings of love light up the front.

As Stephanie discovered, love and lust are not opposing forces but instead operate as a kind of seesaw. Physical desire provides the fuel for love to grow, and love, in turn, feeds some of itself back into lust. So, with this in mind, you can see why the term “making love” makes sense. Literally.

But if that’s really the case, why do so many long-term couples encounter problems with physical intimacy over the course of their relationships? Well, studies show that, over time, couples tend to lose the lusty passion that first drew them to one another. In the US, 43 percent of women and 31 percent of men have experienced some kind of difficulty with physical intimacy during their marriage. But, at the same time, most people in relationships see physical intimacy as an essential part of a healthy relationship.

And neuroscientific findings back that up. The insula needs both an intense physical connection and a deep emotional connection in order to be fully fired up.

So what’s the solution? Well, it may not necessarily require couples to find ways to increase physical chemistry. Instead, they may be able to find nonsexual methods of getting the posterior parts of the insula to fire. Remember that it’s triggered not just by desire but also by things like food? Why not try using that to connect with your partner? You can come up with new recipes, cook together, and share meals. Focus on the flavors and let your brain help you forge that physical connection between you and your partner again.

Grief and loss can have deadly consequences for the body and mind.

One day in 2015, Stephanie’s husband John received a phone call that shattered their world.

It turned out that the persistent pain in his cheek that he’d been experiencing was more than just a toothache. It was a rare cancer – stage IV, salivary gland cancer. The odds of him surviving one year after diagnosis were horrifyingly small.

Yet, he did survive. After an eight-hour operation in which a doctor flipped open John’s cheek and cut the cancer out of his salivary gland, everything seemed to be going well. By the fall of 2017, after various forms of therapy, John looked better than ever before.

But then, in March 2018, he began coughing. He couldn’t catch his breath. And suddenly, his mouth filled with blood. Just before he lost consciousness forever, his last words to Stephanie were “I love you.”

At first, Stephanie refused to believe it. She kneeled and begged the paramedics to bring her husband back to life. And when she finally realized what was happening, she began to scream.

Health risks shoot way up in the 24-hour period immediately after a loss. For example, a person’s risk of having a heart attack increases by 21 to 28 times. And there is, in fact, a rare condition called broken heart syndrome, in which acute stress can change the shape of the heart’s main pumping chamber and cause extreme pain. So, in a way, you can die from a broken heart.

And that’s only the beginning. Months after you experience a loss, you’re still at risk for various bad health outcomes. In the 1960s, a study looked at 4,486 widowers in Britain. In the six-month period after losing their spouses, the widowers were 40 percent more likely to die than a married person of the same age. In the long term, people who experience the death of a significant other have an elevated risk of developing cardiovascular disease, diabetes, and cancer.

Why does this happen? When you’re grieving, your brain is tortured and you can’t think clearly. The amygdala – the brain’s alarm system – is constantly blaring, warning you of danger. Meanwhile, the prefrontal cortex – the regulating and planning system – is underactive. As a result, you have trouble completing simple tasks; your mind is completely preoccupied by your loss. And so, you aren’t taking care of yourself and you’re constantly on edge.

For most people, grief begins to get better within six to twelve months. After this period, you’re still irrevocably altered by your loss, but you feel more able to explore new options and live your life almost as you did before.

However, about 10 percent of those who lose a loved one can’t move past it a year later. When this happens, psychologists call it “complicated grief.” This is a state that’s dangerous for our bodies and minds; we become almost zombie-like in our yearning to reunite with our loved one even though we know it’s impossible.

UCLA psychiatrist Mary-Frances O’Connor and her colleagues conducted a study that revealed the difference between complicated and uncomplicated grief. She showed people photographs of their lost loved ones while scanning their brains. In patients with complicated grief, a certain part of their brain’s dopamine-driven reward system was activated. When faced with the photograph, their brain was still expecting to see and feel their loved one again. On the contrary, the patients without complicated grief understood, deep within their brains, that a photograph of their lost loved one was not a signal of a reward to come but rather a memory of someone who is gone.

The reason why it’s important to understand this is because people with complicated grief often try to deal with their pain by avoiding thinking about the person they lost. They avoid reminders of them and, as a result, they end up using more mental energy than they might spend in facing and processing their grief.

A much better way of dealing with the pain is by facing it head-on, even if it means screaming at the top of your lungs. This is a lesson that Stephanie learned from – of all things – skydiving.

She was in Switzerland a year after John’s passing when some of her friends surprised her with a skydiving session. She was terrified. But the instructor explained to her that screaming when exiting the plane would help her accept and deal with the very normal, rational fear and discomfort. It would even release endorphins – the hormones that affect the areas of the brain responsible for controlling pain and pleasure. Stephanie screamed inside the plane, outside of the plane, and in fact, the entire way down to the ground. She realized that those 40 seconds were the best of her life since she’d lost her husband. In those moments, she was finally able to face the pain of remembering him. She saw him all around her and learned to keep loving him.

Final Summary

The most important thing to take away from all this is:

Love is an essential, undeniable, and universal part of the human experience. By helping us forge and maintain social connections, it assisted greatly in human evolution. It also makes us more creative, sharper, and better thinkers by activating sophisticated parts of the brain. However, the downside to the many benefits of love is that its loss can prove disastrous to our health – that is, if we fail to face the pain head-on and scream in its face.

And here’s some more actionable advice:

Fight off loneliness at all costs.

Chronic loneliness is deadly and it increases the odds of an early death by 25 to 30 percent. So it’s worth taking active steps to avoid it. Try, for instance, volunteering with a local charity. Helping other people will give you a sense of satisfaction and shared humanity that’s similar to what you’d experience in a romantic relationship. And if you personally know someone who’s lonely, don’t try to help them – instead, ask them to help you. Being shown respect and trusted to provide assistance can help a lonely person feel an increased sense of worth and reduce their perceived isolation.

About the author

Stephanie Cacioppo is one of the world’s leading authorities on the neuroscience of social connections. Her work on the neurobiology of romantic love and loneliness has been published in top academic journals and covered by The New York Times, CNN and National Geographic, among others.

Table of Contents

Introduction 1
1 The Social Brain 11
2 A Single Mind 24
3 Passion for Work 40
4 The Love Machine 53
5 Love in the Mirror 66
6 When the Brain Swipes Right 82
7 We’ll Always Have Paris 94
8 Better Together 109
9 In Sickness and in Health 119
10 The Test of Time 139
11 Shipwrecked 153
12 How to Love a Ghost 162
Epilogue: A Holistic Theory of Love 177
Acknowledgments 187
Notes 193


From the world’s foremost neuroscientist of romantic love comes a personal story of connection and heartbreak that brings new understanding to an old truth: better to have loved and lost than never to have loved at all.

At thirty-seven, Dr. Stephanie Cacioppo was content to be single. She was fulfilled by her work on the neuroscience of romantic love—how finding and growing with a partner literally reshapes our brains. That was, until she met the foremost neuroscientist of loneliness. A whirlwind romance led to marriage and to sharing an office at the University of Chicago. After seven years of being inseparable at work and at home, Stephanie lost her beloved husband, John, following his intense battle with cancer.

In Wired for Love, Stephanie tells not just a science story but also a love story. She shares revelatory insights into how and why we fall in love, what makes love last, and how we process love lost—all grounded in cutting-edge findings in brain chemistry and behavioral science. Woven through it all is her moving personal story, from astonishment to unbreakable bond to grief and healing. Her experience and her work enrich each other, creating a singular blend of science and lyricism that’s essential reading for anyone looking for connection.


“Cacioppo blends memoir and science in her debut, an enlightening testament to love’s ability to enhance one’s life… Readers will be both fascinated and moved.” – Publishers Weekly

“Cacioppo’s writing becomes more intimate as her life story stitches closer to her research. Her conclusion is enchanting and uplifting… A beautiful testament to romantic love, scientific passion, and the endless possibility of connection.” – Kirkus

“…an engaging guide through the scientific portions of the book, and her own experiences of connection and loss enrich the narrative. Together, these intertwined strands of science and personal narrative make for a sprightly, illuminating book.” – BookPage

“Filled with a little something for everyone, Wired for Love is a unique take on a memoir that will take you on a journey of grief and healing with a reminder to keep your heart open to all the beauty and pain that life might bring.” – Mindful Magazine

“This fascinating and moving blend of science and memoir proves love’s power to transform and heal.” – Erin Kodicek, Amazon Editors’ Personal Pick for April

“When John and Steph met it was electric, consuming, forever. One might even say ‘wacky’ from the start. But then their love grew to be inseparable, collaborative, joyous, and infinitely inventive. And while their scholarship and devotion to science hit new levels, it was their bond in love that was a joy to know. THIS BOOK CAPTURES THAT JOY.” – Michael Gazzaniga, author of The Consciousness Instinct

“This meditation on love is deep in every sense: in scientific richness, in human insight, and in moving personal involvement.” – Steven Pinker, author of How the Mind Works