The brainwashing is done via neuro-linking, I would imagine. 

I heard them say that the soul is your thoughts, your memories and your characteristics and your loosch, in their system. 

So, loosch is what defines the conditions, also.  That is their ideal world. 

If you can wipe out all the memory, you sort of change a person. You make them like a blank slate for programming. It is one of the tricks they have for making people prone to hypnosis. 

In the Spiritual world, which was the one Hubbard was trying to mimic, shamans can walk through the field to get to images and memories of past events. How do they do that? Scientology and Akamai have come up with a way to alter that. "Washing" the mind.