The BBC has a great piece up about radiologists, specifically those who examine scans of lungs for cancerous growths, who missed a dancing gorilla that had been added to the scan. This doesn’t represent a failure on their part. Far from it.
This experiment is based on the “Basketball Gorilla” experiment where participants are asked to focus on a single aspect of a video, all the while remaining oblivious to an actor in a gorilla costume wandering through the frame. I’ve been subjected to a similar experiment during one of Derren Brown’s stage shows.
As Derren said at the time, those who do not notice the Gorilla should not feel bad. It signifies an ability to focus on a single goal, something that is hugely beneficial. Do one thing, and do it well.