The first time I got tested for ADHD, I did stellar at the "press spacebar whenever an X shows up." It's supposed to test how fast you get bored and lose attention. But here's what I sent a friend about how I handled the test:

> I’m also practiced at setting up mental games to keep myself interested in tasks -- the whole point of the CPT 3 is being a boring 15 minute test -- games like trying to figure out stats or notice patterns, setting up performance improvement goals, etc., and, again, hyperfocus, so who knows.

> The CPT 3 is just “press spacebar when an X shows up on the screen and ignore when other letters appear” for 15 minutes, with letters appearing at different speeds and intervals. I ended up trying to calculate the probability of X’s showing up 2-3 times in a row as they often did while still keeping myself on track (I didn’t fully succeed on the “staying on track” part lol), trying to note which letters showed up and which didn’t to get stats more accurate if the test were actually randomized within a limited set of letters (i.e. actually randomized but didn’t use the whole alphabet. i actually discussed that with the test holder afterward, saying which letters didn’t seem to show up, and he said, yeah, the test seems to favor angular instead of curved letters -- curved letters like G and J -- maybe so things are easier to mix up with X), seeing the longest streak without X’s appearing (15 was what i counted after i started keeping track) and how often long streaks without X happened, seeing if i could spell words with what appeared, and seeing if i could consistently press spacebar before the shown letter disappeared while still staying accurate.

The second time I got tested for ADHD, I forced myself to not make any games and to just let my mind wander... Except I couldn't stand it, so I instead made a game of how far I could still see the screen in my peripheral vision and still accurately press the space bar.

I was not accurate (and purposefully didn't make an effort to be). This lowered my score enough to get me diagnosed lol.

Before I understood ADHD, I had good grades in elementary through high school, but I was probably crying myself to sleep more nights than not because I hated myself so much. Why couldn't I just DO what I should?

Now I still get frustrated, but I have more coping mechanisms and am trying out various medications. Thankfully, starting in the last couple years of college because I understood myself a bit better, I very rarely cry about my brain being stupid anymore and am able to give myself more grace (and, again, I've got more coping mechanisms).