I have dreams where I occasionally learned things, such as the one I had last night.
It started off as a normal dream. One I couldn't discern from reality. I drove to the mall with my girlfriend. We took a long time to find parking. We were walking the mall looking for things to buy for her. Then for some reason there were zombies everywhere. The only weapon I had was a stabbing knife.
So I tried stabbing zombies in the head. The first few I tried stabbing was in the forehead or cranium. They got pissed. They bled none-the-less.
Then they stopped fighting me to explain that the softest part of the head accessible from the front was the temple or from either eye. From behind: right above the neck, right at the hair line. Best done at an upward angle to damage the brain.
Then they went a step further and said it's easier if I pushed them against a wall or the floor and drove my knife into their heads using the wall or floor as a great backing.
Weird lesson, but it makes sense.
EDIT: Additionally: the zombies were walking me through each lesson. I.e. they would grab my hand and tell me what the fuck to do. The ones that talked spoke to me in my own physical voice.