Like Swiss Cheese

Which part of the brain is the one that stores all the memorized stuff like basic multiplication tables and the spelling of everyday words? Because I'm pretty sure mine is full of holes.

Yesterday, I had to really, really think about whether 7+5 equaled 12, or if I was totally crazy. I knew for a fact that 7+6 equaled 13, which made the moment that much more pathetic.

Then this morning, I was composing an email to a co-worker and forgot how to spell the word "integral". Instead, I kept typing the word "intregal" over and over. Which isn't even a word. And because Apple Mail kept flagging it as misspelled, I was convinced the program was malfunctioning. A quick Google search straightened me out, but now I'm not positive I haven't been saying "intregal" out loud to people who definitely know the difference between a real word and a made-up word.