Romantic chemistry is highly difficult to predict, let alone to define. Nevertheless, according to classic research by Helen Fisher—late biological anthropologist and research fellow at Kinsey Institute—it is still an observable neuropsychological phenomenon. Her study, involving 17 participants described as “intensely in love,” showed that regions of the brain associated with motivation and reward were highly active when looking at their loved ones.

Thus, when you hear someone say that they’ve “got chemistry” with someone else, this is likely the cause—namely, activation of brain areas that are brimming with dopamine. However, genuine romantic connection and chemistry are not the only variables that can make our hearts race, palms slicken, and cheeks blush.

Here are two things that can have similar effects to romantic chemistry, but should never be confused with it.

1. Attractiveness

Have you ever had a conversation with someone impossibly attractive, and by the end of it, you were convinced that they were the one for you? You’re not alone if you’ve been in this situation. But, unfortunately, you’re also likely a victim of your neurochemistry. While attraction is certainly an important aspect of connection for some individuals, they don’t necessarily beget one another—nor does it mean that the feeling will be mutual.

According to a 2014 study from Neuroscience and Biobehavioral Reviews, for heterosexual individuals, certain brain regions will be predictably active when looking at an attractive member of the opposite sex. Namely, these regions are:

• Nucleus accumbens. A region key to the brain’s reward circuitry, which processes pleasure, reward, and motivation. It’s usually activated in response to stimuli our brains deem rewarding—including, but not limited to, a really good-looking face. In such cases, this activation is crucial for mating and social significance.
• Medial prefrontal cortex (mPFC). Associated with social cognition, self-referential processing, and decision-making. In the context of attractiveness, the mPFC is what helps you “evaluate” their face, and, in turn, contributes to how desirable you think they are.
• Dorsal anterior cingulate cortex (dACC). Involved in error detection, conflict monitoring, and attention. The dACC is likely what makes it so hard to turn your attention away from someone attractive, especially if they’re a potential romantic interest.
• Orbitofrontal cortex. Linked to the evaluation of reward values, as well as emotional processing, this region is what helps you assess the pros and cons of things around you. With someone attractive, it informs how you’d approach and engage with them.

There’s no denying the similarities between the brain’s role in romantic chemistry and attraction; both heavily affect our reward systems. However, these two phenomena can—and often will—occur in mutual independence. It can be hard to ignore the screaming parts of your brain telling you that the attractive person in front of you is your one true love, but it’s still in your best interest to try.

In most cases, this is your brain assuming there to be chemistry when there may well be none at all—or, at least not yet. Once the attraction is explicitly mutual, and you’ve found other grounds to connect, then perhaps you can say there’s chemistry. But, until then, there’s not much to support the idea of there being anything tangible going on between you.

2. Kindness

We’ve all wondered it before: Are they flirting, or are they just being nice? Perhaps someone gave you a gift, paid you a compliment, or wrote you a kind message. Or maybe your local barista remembered your regular coffee order and made it on the house. These small acts of kindness feel indescribably good on the receiving end, and they feel just as good to enact.

There’s an abundance of research that links kindness to oxytocin, colloquially known as the “love hormone.” Acts of kindness, for both givers and receivers, will cause the brain to surge with this neurotransmitter—which plays an integral role in social bonding, trust, and attachment. However, to assume that anyone who’s kind to you must be into you can put you at severe risk of disappointment.]

This isn’t to say that assuming chemistry from kindness is foolish. If anything, it’s intuitive; people who are kind to us tend to have a certain inviting “glow” about them. This, however, is also a neurochemical product.

As Jessica Andrews-Hanna—researcher and associate psychology professor at the University of Arizona—explained about the warm glow of giving, when we give something to others, it leaves a warm fuzzy feeling in ourselves that persists over time and creates a glow of kindness. This warm glow can be created by giving physical gifts and by engaging in other acts of kindness like complimenting others.

Notably, Andrews-Hanna’s descriptions of the neurological effects of giving and receiving kindness are, unsurprisingly, also similar to romantic chemistry: “Evidence from brain imaging also suggests that both giving gifts and receiving gifts activate core areas of our brain associated with reward and pleasure.”

That glimmer in someone’s eyes, the warmth in their smile, or even the excitement in their voice when they do something nice for you doesn’t automatically signal romantic interest. These outward signs of kindness, while heartwarming, are better evidence of someone’s capacity for empathy; they aren’t necessarily a bold declaration of deeper feelings. Confusing these moments for chemistry risks misinterpreting genuine goodwill as something it’s not—which will be awkward for you, and hurtful for them.

Again, while kindness may evoke similar chemical reactions to that of romantic chemistry, they too can occur independently. Simply put, it’s best not to read too deeply into someone’s random act of kindness; instead, take it at face value. After all, kindness is something we can—and should—afford to anyone. Assuming that you, and others, are only worthy of kindness because of your potential as a romantic interest is a slippery slope.