Seems that "suppressed" means it isn't affecting me, I can see that by the intelligence showing 17. Just odd why it stayed there.
FYI I restarted and now it's gone.
Ok, after my fight with a spectre, this miasma of dull mindedness is stuck on! It is killing my intelligence, from 17 to 7. Obviously I can't continue the game unless it is removed, any ideas?