If you’ve ever had a crush, you’ll know how crazily it can get in your head—and in your heart. That heady attraction to someone, be it your barista, your friend of a friend, or some total stranger in a hoodie bearing your favorite band’s logo, can get you tingly one minute and flustered the next. Crushes have a way of making even the most level-headed among us float (or spin). But a lot is going on underneath that burst of feeling—and it begins with your brain chemistry.
The Brain’s Chemical Cocktail
When you fall under the spell of someone, your brain starts a full-blown chemical orchestra. It begins with oxytocin, which is commonly referred to as the “bonding hormone,” says Dr. Lamont Moss. It gets dopamine going, which is the neurotransmitter that increases your attention, builds anticipation, and makes you keep coming back for more. That’s why you’re rewinding your most recent conversation or creeping through their playlist like you’re at a crime scene.
Dopamine’s rush of pleasure is also behind those mini-highs you experience from each little interaction. Next are the endorphins, which join in the party. It’s all super addictive—literally. That “can’t eat, can’t sleep” sensation? That’s your body responding to a neurochemical rush that tricks the brain into thinking it’s a drug.
Why You Feel Nervous (and a Bit Unhinged)
But not everything about crush chemistry is rainbows and unicorns. Your body also releases adrenaline and cortisol, the stress hormones associated with your fight-or-flight response. That’s why your heart pounds, your palms are sweaty, and you might feel an odd combination of thrill and horror when your crush passes by. Throw in changing serotonin levels, and you’ve got a formula for emotional whiplash. Dr. Kate Truitt points out that at the height of a crush, the amygdala (your emotional and fear center in the brain) can overwork itself, leaving you feeling hyper-vigilant and, at times, excruciatingly self-conscious.
Why Do We Get Crushes at All?
Biologically, crushes are baked into us. Evolutionary psychologists think that they act as nature’s way of nudging us in the direction of connection, reproduction, and survival. Dr. Stephanie Cacioppo explains that our brains are hardwired to find emotional closeness and support. A crush is one method by which a rive sets in. At a subconscious level, we can also be attracted to individuals on the basis of hints associated with health and genetic compatibility, such as smell or sound. Yes, your nose may know more about the right person for you than your dating app.
The Psychology of a Crush
While biology sets the stage, psychology fills in the details. Dr. Leigh Ann Vaughn calls the early stages of a crush a “fledgling relationship”—one where constant thoughts, fantasies, and emotional investment are normal, even if there’s been zero romantic interaction yet. Scientific studies confirm that what we perceive as similarity is a leading motivator of who we fall for. We’re drawn to that person who reflects us—similar interests, familiar values, even homies from the same hometown can make one feel immediately special. Charles Chu’s study at Boston University attests that even the smallest level of commonality can ignite a genuine emotional connection.
Familiar Faces, Familiar Feelings
There’s also something to be said about familiarity. Those we encounter regularly, or who bear a resemblance to someone from our past, are more likely to inspire romance. This is partly because repeated exposure evokes trust, and partly because the brain is wired on familiarity. That’s why you may fall in love with the person you take the elevator with every morning—or someone who is a reminder of a first love.
How Crushes Influence Behavior
Crushes can alter how we present ourselves to the world. You may discover you’re walking home from work a different way, experimenting with a new hairstyle, or suddenly Instagramming more—anything to maximize your visibility. Even a tiny reaction from your crush—a smiley reply, a chuckle at your joke—can give you a huge dopamine boost. At times, we behave in ways that feel unfamiliar or even slightly embarrassing. Yet all of these behaviors are connected to the reward system of the brain, perpetually seeking the next little flash of connection.
Fantasy vs. Reality
One of the most compelling aspects of having a crush is how much of it occurs in your mind. Because crushes tend to emerge before actual intimacy, it’s simple to put your fantasies and hopes onto the other individual. Therapist Dr. Donna Oriowo says it’s easier to idealize someone you don’t know because they’re a blank slate. That fantasy can heighten the emotions, sometimes even stronger than if you were in a relationship.
Yes, People in Relationships Get Crushes Too
Crushes aren’t exclusive to singles. Studies have proven that individuals in committed relationships get crushes as well, and usually choose not to pursue them. For others, a crush becomes a harmless flight of fancy or an appreciation for what they love about their partner. In other situations, it even serves as a bonding agent, reminding individuals to refocus on their existing relationship rather than wandering away from it.
When a Crush Becomes Too Much
Of course, there is also a darker side. If your thoughts regarding someone become too obsessive or begin impacting your daily life, it’s time to take a pause. Obsessive crushes can result in insomnia, anxiety, or ignoring work and relationships. Setting time limits for thinking about your crush, talking it through with a friend, or channeling the energy into something creative can help. If the crush involves someone off-limits—like a boss or while you’re in a relationship—therapy or journaling may be a healthier way to process it.
How Hormones Influence Attraction
Believe it or not, even birth control hormones can influence who you’re attracted to. Certain research indicates that taking the pill can change scent preference and attraction, so you could start feeling differently about your partner once you stop taking it. That adjustment can quietly affect relationship satisfaction or long-term compatibility. This shows just how much our biology controls how we feel—even when we don’t know it.
Crushes Are Human
Crushes are wild, wonderful, and sometimes utterly overwhelming. But under the fluttering sensations and sleepless nights lies a complicated mix of biology, psychology, and social pressure. Whether your crush leads to something real—or stays a lovely what-if—it’s a very human experience that recalls how potent attraction can be.