If you’ve ever fallen madly in love with someone, you know how the pitter-patter of your heart can make the world seem like a magical place. But the reason you feel this way for someone can be hard to pinpoint, even for scientists and psychologists who have spent years trying to understand what makes us fall in and out of love.

While there is certainly no one answer, researchers are beginning to find some clues as to what makes our hearts flutter and our heads spin. For example, when we are in love with someone, the feeling comes from a combination of factors, including the person’s attractiveness, personality traits and their level of intimacy with you. In addition, the release of a cocktail of hormones, such as dopamine and adrenaline, can cause our cheeks to flush, our palms to sweat and our hearts to race.

A recent study by Helen Fisher, an expert in romantic love from Stony Brook University, put 37 people in love into an MRI scanner to see what was happening inside their brains. She found that when we are in love, an area of the brain called the ventral tegmental area becomes active, producing dopamine, which triggers feelings of yearning and desire. Another part of the brain, the caudate nucleus, lights up when we are in love. This region of the brain is associated with reward, motivation and cravings, and is similar to areas that light up in people who are taking cocaine.

In addition, when we love someone, we are often able to anticipate their needs and wants. This may help explain why, when we’re in love with someone, we try to please them and put their needs before our own. But in a healthy relationship, we balance this need for companionship with a sense of self-worth and autonomy, which can prevent us from being codependent or falling into the “I need you” trap.

If we look at the history of love, culturally and historically, it’s easy to see that we have evolved to keep our families, friends and partners bonded through emotion. However, many of us still struggle with understanding the nature of love, which can be tricky when it’s a subject for discussion at dinner tables and in bars.

Research suggests there are three main types of love: passionate, compassionate/companionate and unrequited. The first is characterized by intense feelings of attraction and romantic longing; it can also be accompanied by jealousy, insecurity and lust. Companionate love, which is based on trust, care and affection, and a commitment to a shared future, can be seen in close relationships between parents and their children. Finally, agape is an unconditional love of selflessness and giving that’s typically seen among religious believers. But evidence suggests that most people experience a mixture of these different love styles. This is referred to as a fusion love style, and is often what is viewed as true love.