If you’ve ever stood in public transport, waited in line at a café, or just talked on your phone while walking down the street, there’s a big chance that you’ve been eavesdropped on.

When you think about listening to conversations of other people, words like “prying” and “nosy” pop right into your head. However, more often than not, these brief interactions are so confusing, they can make anyone stop and listen. 

Bored Panda reached out to Dr. Lauren Emberson, a psychology professor at the University of British Columbia, to find out more about why we are so fascinated by what strangers have to say. She and her colleagues did a study called Overheard cell-phone conversations: when less speech is more distracting. 

The researchers were trying to see whether the thinking abilities of 41 volunteers were most affected by listening to two people talking, a monologue, silence, or a “halfalogue”, a one-sided conversation. The results showed that overhearing a “halfalogue” is distracting and decreases performance “on cognitive tasks designed to reflect the attentional demands of daily activities.”

When it comes to listening to cell-phone conversations, our brains are trying to break down what the person on the other end of the call is talking about, which makes it harder for us to concentrate. “By contrast, overhearing both sides of a cell-phone conversation or a monologue does not result in decreased performance.”

However, it seems that not listening to private conversations is difficult because our attentional systems do it automatically. “Our study showed that even when we instruct people not to listen to the conversations when they were doing attentionally demanding tasks, their attention was specifically drawn away from their task when they were listening to a cell phone conversation or a ‘halfalogue,‘” the professor explained. 

It is not exactly clear why that happens. Dr. Emberson told us that there’s some evidence that the unpredictability of the speech could be the problem here. “Remember that in a cell phone conversation, speech starts and stops,” she mentioned.

“We found that attention is drawn away specifically when the speech starts, not during the silences, suggesting that the unpredictable cell phone speech is hard for you to process compared to a dialogue (even when the speaker changes in a dialogue, it’s not as distracting).” 

When asked if people eavesdrop consciously, the professor said that it’s definitely true and that she sometimes does it too: “The inspiration of this study, though, was a feeling that I and many others have that you can’t help but eavesdrop on these cell phone conversations.” 

She added: “I really didn’t want to listen to them but I felt I couldn’t filter them out. And that’s why we tested whether it is an automatic function of your attentional system to tune your mind into them and sure enough, that’s the case!”

The study revealed that overhearing conversations can make us feel annoyed and irritated. Yet, so many people take these interactions to the internet and see it as a great source of entertainment. Dr. Emberson has offered one explanation for us: “These convos were very irritating at a time before texting when everyone was talking on their cell phones and it was very noisy with those conversations in public spaces like buses.”

“Now most people text (myself included) so they might be more of a curiosity than anything else,” she mentioned. Her personal opinion is that people find such convos bizarre and funny because “they are out of context (you only hear one half) and that engages your curiosity in a way.”

John Locke, a professor of language science and author of Eavesdropping: An Intimate History, mentioned another reason why we may see one-sided convos as irritating. When someone is talking quietly, it grabs people’s attention. However, when they are being loud, many become annoyed. 

The reason behind it is that loud social behavior violates one basic law of nature: “We don’t like donations. We don’t like it when people present us with information about themselves that we’re not seeking.”

“[People] want to know what you’re truly like inside, not what others want them to think,” Locke said. “We love it when we get something that’s truly genuinely true about others and so we still prefer taking it, or if not taking it, extracting clues on our own.”

We are very interested in how other people act in private. Most of our lives we spend alone with our thoughts, and it’s interesting to see how others behave when they think no one is observing them. “The only way you can know that is by looking at other people who think that they’re alone,” John Locke mentioned. 

Still, one thing we’re sure of—listening to strangers’ conversations can be hilarious. And the fact that we hear only a fraction of the conversation that doesn’t make any sense to us makes it even funnier.