Charlie - Grey cells.
 

How many of the grey matter do you think he lost in the big brother house?

I think his remaining brain cells suffer from agoraphobia there is such a wide open space in his head.

Seriously, at times I think he makes himself appear dimmer than he is, because he thinks it will win him popularity, this is clearly fake as "Alison Wonderland", "7 is unlucky" and the flour in the kitchen thing were just acts taken too far, but his tirade against Freddie and subsequent "I don't want to talk about it anymore. No! Shut it! Not another word!" was far from the behaviour of an intelligent man.