[0]: https://en.wikipedia.org/wiki/Inattentional_blindness#Invisi...
edit: someone should train it on MyHouse.wad
Objectively, Simons and Chabris (and many others) have a lot of data to support these ideas. Subjectively, I can say that these types of tasks (inattentional blindness, change blindness, etc.) are humbling.
Even having a clue why I'm linking this, I virtually guarantee you won't catch everything.
And even if you do catch everything... the real thing to notice is that you had to look. Your brain does not flag these things naturally. Dreams are notorious for this sort of thing, but even in the waking world your model of the world is much less rich than you think. Magic tricks like to hide in this space, for instance.
We don't memorize things that the environment remembers for us if they aren't relevant for other reasons.
What this demo demonstrates to me is how incredible willing we are to accept what seems familiar to us as accurate.
I bet if you look closely and objectively you will see even more anomalies. But at first watch, I didn’t see most errors because I think accepting something is more efficient for the brain.
The people were told to focus very deeply on a certain aspect of the scene. Maintaining that focus means explicitly blocking things not related to that focus. Also, there is social pressure at the end to have peformed well at the task; evaluating them on a task which is intentionally completely different than the one explicitly given is going to bias people away from reporting gorillas.
And also, "notice anything unusual" is a pretty vague prompt. No-one in the video thought the gorillas were unusual, so if the PEOPLE IN THE SCENE thought gorillas were normal, why would I think they were strange? Look at any TV show, they are all full of things which are pretty crazy unusual in normal life, yet not unusual in terms of the plot.
Why would you think the gorillas were unusual?
Furthermore, even what we attend to isn't always represented with all that much detail. Simons has a whole series of cool demonstration experiments where they show that they can swap out someone you're speaking with (an unfamiliar conversational partner like a store clerk or someone asking for directions), and you may not even notice [0]. It's rather eerie.