That is because your understanding is faulty.
The brain does not host memes. The CNS does not host memes. The
organism hosts memes.
Memes take input/run over the substrate of the organism. Changes in
the limbic or muscular system can change the environment of the
memesphere, giving rise to different memecologies as a reaction to the
change in environment. Memes are more abstract entities than can be
pinned down to some location in the brain, they exist as
informational, not physical, abstractions. When I state, `there is no
YOU, there is just the emergent face of your memesphere,' I literally
mean that your informational ecology, existing in both the environment
of your body and its environment, produce the fiction of you.
Hope that clears things up a bit.