Blind Dates and Heart Rates

While fireworks have been filling the skies over this past week, sparks flying between two people pursuing a romantic connection is less of a given. But there might be a way to find out which couples are destined to click: if their heart rates synchronise when they see each other! Julia Ravey…

Julia - They look all right actually. Definitely not. Oh, that's a cute dog. Right up my street. It's a match. When it comes to finding a potential partner, it's hard to know what to look for. A great sense of humor, intelligent conversation, a matching pulse. Well, maybe the last one is what matters. With millions of people in the UK turning to dating apps, our criteria for finding ‘the one’ can be applied before we even go on a date. But sometimes no matter how much a person may be your type on paper, when you meet them face-to-face that connection, that spark is missing. So we decide 'they're not for us' and we move on to the next swipe right. A big question I've always had is what is that spark? So many of us use it to determine if a person is a good fit, but what gives us the physical green light? I spoke to...

Eliska Prochaskova - Eliska Prochaskova and I'm a researcher from Leiden University.

Julia - Who thinks she may have cracked the connection code.

Eliska Prochaskova - When people are looking for a romantic partner, they want to have chemistry. They want to feel a connection with that partner. And while this is something that everybody says, it's really hard to describe what it actually is and can we measure it?

Julia - Eliska and her colleagues, tested this by setting up a blind date experiment. Two people would enter compartments of a space separated by a sliding hatch. They would then do a '3, 2, 1, big reveal' for a few seconds to let the participants rate each other on physical attraction alone. They then let the dates chat for a few minutes and just be in each other's company.

Eliska Prochaskova - At the end, we asked them again how attractive the partner is. We also asked them whether they wanted to go on another date. This really allowed us to see how the attraction changes over the period of dating, and whether they become more attractive.

Julia - This was all while wearing devices, which measured their heart rates, how sweaty they got, and track their eye movements. But these devices definitely didn't get in the way.

Eliska Prochaskova - They completely forgot they're wearing them and we could see a person running and wanting to go to the toilet. We had to stop that person because we're like "We can literally see what you're doing".

Julia - Although the participants in the study show gestures we associate with being attracted to someone, like eye contact and smiling, Eliska found a different measure was the best at predicting attraction.

Eliska Prochaskova - We measured all different types of expressions. So, we measured nonverbal, smiling, laughing, and flirtatious behavior, we also measured eye contact. What we realised was that the main predictor of this click or this chemistry which people have, was the synchrony between the partner's heart rates and their skin conductance, which are unconscious responses which you cannot control. The more synchronized, the more attracted the partners become to each other.

Julia - Why do you think heart rates matching up might influence attraction?

Eliska Prochaskova - At the moment, scientists know that synchrony between people's physiology like heartily skin conductance happens in many different contexts. It's a phenomenon which we, for example, observe between mother and child, when there are, for example, hugging or when they're playing. From that, we know that this kind of synchronicity often leads to powerful bonding.

Julia - With so many of us now dating online this research can teach us how to increase the chance of having that spark on a first date.

Eliska Prochaskova - About 50 million people who are dating online, using different types of apps, they base their choice on attractiveness. What we observe in our study, what is really important for two people to really establish this connection, is a level of emotional synchronicity, what the physiology actually measures. That means that it's important that people actually put their emotions out and therefore reveal their emotions in order for the other person to explore them, to see them, and also feel them in their own body.

Julia - So there you have it, be open and vulnerable or a first date may be the key for allowing that spark to ignite. Or alternatively, ask your date to come equipped with a heart rate monitor, and put your scores on the doors at the end of the night. "Second date? Nah mate. You were a solid 74 beats per minute, when I was running on an 81. All the best for the future."