Delete mode

An automatic reflex of the human brain that makes you forget everything you have previously known the moment you actually need it.

Some things that trigger delete mode are:

a) being on stage
b) being in the presence of a very attractive person
c) taking a very important test

"I can't believe I forgot the lyrics to my song at the talent show! I swear I knew every single word of it, but when I was supposed to actually sing it my brain went on delete mode!"