Getting Smarter Is Hard

“When you start the game, it will start at the 2-back level. This means that you need to remember if a letter was repeated or a box appeared in the same location 2 times ago. In our example, if the third letter said is the same as the very first one, that’s an audio match. If the box appears in the same location as where the first box appeared, this is a visual match. Press “A” for visual matches, “L” for audio matches and both when both match. Continue to press these keys whenever the present squares/letters match what appeared/was said 2 times ago.”
 — As long as you’re already smart enough to understand the directions, this “game” (ha!) could make you even smarter. According to science writer Dan Hurley, playing Call of Duty also works as does something called mindful meditation. (But what if meditating makes you sleepy?) Or you could do nothing and stay perfect.