First is their most famous video, involving basketball passing. As the video explains, you'll need to watch the players wearing white and count how many times they pass the ball (and note that there are two balls in play!). It takes a surprising amount of concentration. Concentrate and count. It only takes a minute:
How did you do?
Perhaps more importantly, would you like to try out more videos like this? Good, because Simons and Chabris have tons of them. One of my favorites is the movie perception test. Give it a shot:
The queen's private secretary will start an urgent phone tree. Parliament will call an emergency session. Commercial radio stations will watch special blue lights flash, then switch to pre-prepared playlists of somber music. As a new video from Half As Interesting relates, the British media and government have been preparing for decades for the death of Queen Elizabeth II—a procedure codenamed "London Bridge is Down."
There's plenty at stake when a British monarch dies. And as the Guardian explains, royal deaths haven't always gone smoothly. When the Queen Mother passed away in 2002, the blue "obit lights" installed at commercial radio stations didn’t come on because someone failed to depress the button fully. That's why it's worth it to practice: As Half as Interesting notes, experts have already signed contracts agreeing to be interviewed upon the queen's death, and several stations have done run-throughs substituting "Mrs. Robinson" for the queen's name.
You can learn more about "London Bridge is Down" by watching the video below—or read the Guardian piece for even more detail, including the plans for her funeral and burial. ("There may be corgis," they note.)