Hey guys and gals! Here is my 100% Achievement Guide for Infliction!
After the "Confronting your demon" Achievement with the big guy and his meat cleaver, turn on the power to the elevator to be transported back to your kitchen.
While here, pick up memory 25 and you get transported back to said asylum.
Turn around and you see a door to enter, go through there and enter a set of double doors. Go through to a room on the right now and you see two switches.
Flick the left switch on first, but WAIT until the lights above these switches get to 5, as soon as it hits 5, flick the right switch and bye bye ghosty boy!
Go to 42:00 in my video to see where and how this unlocks.
Hope This Helps!