The Eye-Contact Hormone
In Korean, there is a vivid expression for the moment two people fall in love: nun-i mat-da — literally, "their eyes met." It captures something every culture recognizes but few languages name so precisely: that mysterious spark when two gazes lock and, for a split second, the rest of the world falls away.
When we are walking down the street and our eyes accidentally meet a stranger's, most of us look away by reflex — a social contract so deeply ingrained it feels like instinct. Back when I was in college, though, it was not uncommon to see two young men whose gazes happened to collide on the sidewalk, and when neither blinked, the tension would crackle: "What are you looking at?" — followed by fists. A pointless standoff, a contest no one could win. I am a little embarrassed to admit it, but I have been on the receiving end myself. During my military service, I was sitting in a bar when my eyes met those of a man walking by. I did not look away quickly enough. He muttered something, then threw a punch without warning. Instinct took over — I hit back. The result? I ended up paying his medical bills.
But when the person on the other end of that locked gaze happens to be someone of the opposite sex, the story changes completely.
What body part do men and women notice first when they meet someone new? In 2018, a British eye-drop manufacturer surveyed a thousand men and women across the UK on exactly this question. The answer, for both sexes, was the same: the eyes come first. Men ranked what they notice in women as eyes, smile, breasts, hair, weight, legs, clothing, buttocks, height, and skin. Women ranked men by eyes, smile, height, hair, clothing, weight, skin, face shape, buttocks, and nose. Contrary to the tired stereotype, breasts came in only third for men. A company spokesperson told a British newspaper, "This study shatters the assumption that men look at a woman's breasts first." I did harbor one reasonable suspicion, though: perhaps a company that manufactures artificial tears had a quiet vested interest in nudging the data toward eyes.
A Culture Shock in Eye Contact
Shortly after the bar incident, I traveled to Canada for a language program — and what I encountered there rewired my entire understanding of how eye contact works between strangers. In Korea at the time, if your gaze collided with a stranger's on the street, the options were limited and blunt: glare back, look away instantly, or cast your eyes to the ground. There was no fourth option. But Canadians? When they caught your eye on the sidewalk, they smiled and said, "Hi!"
About two weeks after I arrived, a blonde woman walking toward me looked me right in the eye, flashed a warm smile, and said, "Hi!" I had never experienced anything like it. My brain — still running on Korean social software — leapt to the only conclusion it knew: Maybe she likes me? I followed her for about twenty meters before the absurdity dawned on me. It is a memory that makes me laugh every time.
When two people of the opposite sex make eye contact and neither looks away — when they hold each other's gaze with quiet, mutual awareness — a process of self-referential cognition has begun. The locked gaze stirs emotions in both parties, drawing each into deeper focus on the other and, eventually, into attraction. Eye contact is itself a form of nonverbal communication; through it, a wealth of emotional information flows silently between two people.1
Tuning Your Gaze with Oxytocin
Does oxytocin shape first impressions when we look at someone of the opposite sex? Dr. Andrew Bauer and his team at the University of Bonn recruited eighteen men in their twenties, had them inhale oxytocin, and then showed them photographs of 302 women they had never seen — each image flashed for just three seconds. Throughout the process, the researchers tracked brain activity using MRI and PET scans. Participants rated each woman's attractiveness on a scale of one to nine while the researchers mapped their dopamine-release patterns. The result was unambiguous: men who had inhaled oxytocin rated the women as significantly more attractive. Raise someone's oxytocin, and the people around them literally start to look more beautiful.
A second study, with fifty-two male participants, revealed something equally striking: after inhaling oxytocin, men spent more time gazing at the eyes of the women they were shown. We read other people through their gaze — the movement of their pupils, the rhythm of their blinking. When oxytocin levels are artificially raised, men linger longer on a woman's eyes, instinctively trying to decode what lies behind them. One hallmark of autism spectrum disorder is difficulty sustaining eye contact, which in turn makes reading others' emotions far harder. But when oxytocin levels rise, the ability to interpret facial expressions and emotions improves — even in individuals on the spectrum. In everyday language, oxytocin sharpens your social radar. To put it more generously, it can make you the most perceptive person in the room.2
Here is where the story folds back on itself in the most satisfying way: eye contact itself raises oxytocin. Appearance matters in a first impression, certainly — but looks alone do not determine whether someone warms to you. When you genuinely listen, show empathy, and respond with care, the other person's oxytocin rises. And this principle extends well beyond romance. Researchers studying job interviews found that applicants typically hold the interviewer's gaze for forty-five to sixty percent of the conversation. When applicants were instructed to make minimal eye contact (under forty-five percent), extensive eye contact (above eighty percent), or a moderate amount (forty-five to sixty percent), a clear pattern emerged: interviewers gave more negative evaluations to candidates who looked away too often — but also to those who stared too intensely. The sweet spot, as with so many things, lay in the middle.3
We communicate through language. And yet Tolstoy — a man who spent his life wielding words with extraordinary precision — once declared that "language is not an adequate tool for communication." He went further, insisting that language is, in many cases, a lie. Few writers have ever produced more words; fewer still understood their limits so clearly. Throughout his works, Tolstoy returned again and again to the eloquence of nonverbal exchange — especially the gaze. In War and Peace, he writes:
Though separated by language, the most powerful act of communication between them was the silent meeting of eyes.
In Anna Karenina, another passage captures this with striking economy: "Levin met Kitty's gaze, and through her eyes he understood that she was thinking the very same thought." "Her feelings had somehow crossed over to him. He, too, was suddenly bright and joyful." "The flame of joy burning on Kitty's face seemed to spread to every person in the synagogue."
If the language of the eyes carries this much power in human connection, then the importance of oxytocin becomes hard to overstate. Reader, do you want to win someone over? Then look into their eyes — gently, steadily — and let the oxytocin rise. You will be surprised how quickly the love battery charges.
The Day She Entered My Heart
I first met my wife during my language study in Canada, at the home of an elder from a Korean church. A handful of Korean-Canadian students — most of them a couple of years younger than me — were gathered in one room, chattering and laughing in English. My English was barely functional at the time, and since they were all women, I felt too awkward to join in. I bowed hello, retreated to a corner, and sat there like a propped-up sack of grain — the Korean expression kkwoda noeun boritjaroo captures it perfectly. My wife had just graduated from high school and finished her first semester at a local nursing college: a fresh-faced university freshman. We exchanged polite hellos, but neither of us felt so much as a flicker of interest in the other. During that year in Canada, homesick for the warmth of Korean community, I attended the Korean church regularly. My future wife and I became friends in that natural, unforced way that church communities tend to produce. But romance? Not a trace.
A year passed. I returned to Korea and dove back into my third year of university as if we had never met. Then, in my fourth year, came a coincidence that would rewrite my entire life: I was offered the chance to return to that same Canadian city, this time as an exchange student. I went. I saw her again. And still — nothing. No spark, no pull.
As my exchange semester drew to a close, I found myself wanting to stay longer. I extended for a second semester. That small decision turned out to be the most important one I have ever made.
One summer afternoon, I was sitting by a library window, sketching out my life ten years into the future. In ten years, I will be a professor, probably on a mission field somewhere. To get there, I would need a PhD. Before that, a master's degree. I decided to pursue both right here in Canada. But as I mapped it out, the faces of older Korean students I had known — expats who had grown older alone in a foreign land — floated one by one through my mind. I resolved, with a boldness almost comical in hindsight, that I ought to get married relatively soon. I was twenty-three years old. Walter Trobisch's I Married You advises that couples should experience at least all four seasons together before marrying. By that math, I needed to meet someone now to have that year behind me in time.
Lost in these audacious calculations, I paused to pray. "Please let me meet the person who will become my partner for life. And if she is already nearby, help me recognize her."
The moment I finished, my future wife's face rose into my mind as vividly and unmistakably as the full moon on Chuseok night.
Young as I was, I had always carried a mental portrait of my ideal spouse. First, because I had no musical talent whatsoever, she needed to be musical. She needed to be beautiful — that went without saying. And I wanted someone who shared my dreams, someone willing to go abroad with me for a life of mission and service. Now the pieces locked into place with a click I could practically hear. My wife's father was a pastor; she had been playing piano for church services since she was a girl. After finishing nursing school, she planned to attend a music conservatory to study piano. And when I actually looked at her — truly looked — was she not strikingly lovely, with a quiet elegance I had somehow failed to notice? She was the woman I had been imagining all along. How had I been so blind?
That was the day she entered my heart.
Even after this revelation, our first actual date did not happen for three full months — not until October. One day at choir practice, where I sang bass, she sat down beside me and patiently walked me through the score, line by line. When we had practiced enough, I summoned every ounce of nerve I had: "What did you do for your birthday last week?" She answered as though she had been waiting for exactly this question: "Why — if I say nothing, are you going to take me to a movie?" Green light. I clenched my fist under the hymnal and whispered a silent, exultant Yes!
A few days later, we went downtown to see It Could Happen to You, starring Nicolas Cage, and then had dinner together. We talked about everything — hobbies, favorite music, books that had left a mark. Over the meal, I slipped in the question that mattered most: what she wanted to do after graduation, and whether she had ever imagined living abroad in service to others. Her answer sealed the final item on my mental checklist: someone who will not only love me but embrace my calling, too. I have no idea what her oxytocin levels were that evening. Mine, I am fairly certain, had shot clean through my skull and into the stratosphere. From that night until I returned to Korea the following February — roughly four months — I was almost certainly drunk on oxytocin the entire time. The whole world seemed to glow. Everyone in it looked beautiful.