You know what REALLY works GREAT for memory erasing? Getting knocked out.
The brain had a tremendous capability of removing traumatic events from your memory if they lead to something like losing consciousness. People who actually get knocked out RARELY remember the events directly leading up to losing consciousness. So when someone tells you they were doing this and that and then they lost consciousness - they're full of crap and lying to you.
It's almost like those who like to play unconscious inside some restaurant to avoid paying the bill and you pick up their hand and try to drop it on their face. The unconscious person will have their hand smack them in the nose while the faker will almost ALWAYS find a way to not let their hand hit them in the face. It can be almost comical as they keep doing various maneuvers to make sure their hand can't hit their own face as you keep moving it up and dropping it (and even directing it to hit them in the face), but they won't let it happen - particularly if they'd been drinking. It can get DAMN FUNNY!!
Someone's who's REALLY unconscious won't be able to control their limbs and extremities, much less direct them to somewhere else - yet when you hold their own hand over their own face and drop it so it'll hit them on the nose if they don't stop it, you can REALLY tell the difference if their conscious or not.
I kid you not, it's hilarious to the degree these people will go to to continue playing their "unconscious" game. I'm sure Paw-Paw has some good stories. I KNOW LawDog does!
