Yesterday I tried something slightly mischievous during a virtual keynote.

I’d been talking about human decision-making and, in particular, how we focus our attention on the things we think are relevant. Which means we can completely miss other things going on around us.

After my session, there was a second speaker before we came back together for Q&A. Since my camera was going to be off while they were speaking, I thought I’d run a tiny experiment.

I changed my shirt; from a light blue work shirt to a black polo shirt. Then I switched my camera back on for the Q&A and said absolutely nothing about it. Just to see if anyone noticed.

A few eagle-eyed participants spotted it and commented in the chat. One even asked if I was an AI deepfake...

Now, they may well have been the exception. Most people might not have noticed at all. And, frankly, why should anyone pay attention to what I’m wearing during a keynote?

I have absolutely no idea what this proves. It certainly wasn’t a controlled experiment, so I'm not claiming to have been unable to replicate the Invisible Gorilla experiment.

But I do rather like the fact that I’d spent half an hour talking about how our brains decide what deserves our attention; only to discover that, for at least a few people, theirs had apparently decided that my change of shirt was highly significant.

We don’t necessarily get to choose what other people’s brains decide is relevant.