Back to level 3 (and let's not mess with the bomb for now). When you enter the corridor of flesh to the right, you'll need a Psychic Nullifier in your inventory or the Mental Block perk, or you'll suffer up to six mental attacks (you're more vulnerable with a high PE, so Booze will protect too, sort of). The first three only deal damage, more if you have a high PE. The fourth will deal more damage, give you a crippled eye (can be healed as usual) and lower your PE permanently by 1. The fifth will only deal significant damage if you're a Berserker and/or a Childkiller, but will lower your IN permanently by 1. The sixth doesn't deal any damage, but will lower your IN and PE yet again by 1 permanently (which is bad enough). Your NPCs if you have any will also take increasing amounts of damage, always more if you're a Berserker or Childkiller, and what's more they won't be protected by Mental Block, although they'll be completely safe if you have the Psychic Nullifier (which means that they all picked up one too, I suppose). Sweet innocent Dogmeat is unaffected, though. Once you've been through the corridor you won't be hit again if you go back.