Sometimes you read a study and halfway through you think: okay, I get where this is going, but why are there suddenly three prefrontal regions, a sender–receiver paradigm, and wavelet coherence living rent-free in my head? That was precisely my experience with this new study on deception and social distance. It’s impressive work, but also very technical. The press release helped me translate it back into human language. And then it clicked: this is about something we all recognise.

Rui Huang and colleagues looked at how people lie (the “senders”), but especially at how others pick up—or fail to pick up—those lies (the “detectors”). They didn’t use surveys or hypothetical scenarios. They used fNIRS hyperscanning, measuring two brains simultaneously while people tried to influence each other.

In one sentence: what happens in a brain, and between two brains, when someone tries to deceive you?

What did they find? Detectors fall for gains more easily than for losses. And they stumble even faster when the person across from them is a friend. You’d expect people to scrutinise friends more closely. Instead, the opposite happens: trust lowers your guard. You can see that shift in both behaviour and brain activity. Friends’ brains sync more strongly in regions tied to reward and risk evaluation. That may sound like “being on the same wavelength,” but here it really means this: you slide into the other person’s reasoning just a bit too fast.

I was struck by how clearly this synchronisation predicted what happened next. When deception succeeded, the orbitofrontal and dorsolateral prefrontal cortices synced up more strongly. And yes, I’ll forget those regions again in an hour. But here’s the key point: a machine-learning model picked up on that synchrony and used it to forecast whether the detector in a specific trial would fall for the lie. It managed that within the first seconds of the interaction—an early neural signature of “you’re going to believe this.”

The study sits far from everyday classroom practice, but it touches something very familiar. Proximity shifts your judgement. Students trust their friends more readily than their teachers. Schools sometimes rely too much on informal impressions because the team knows each other well. Trust matters, but it also creates blind spots. This study makes that painfully clear: the effect isn’t just psychological; it’s rooted in the brain.

It’s not research that leads to immediate recommendations, and that’s probably for the best. No one wants fNIRS at parent–teacher conferences. You don’t either. But it does offer insight into how quickly and automatically social distance shapes our thinking. And how hard it is to stay objective when gain, loss and relationships are all at play.

If you want to dive deeper, the original paper is heavy, but the press release is an excellent start.