mechanic head blobbing when walking maybe war injuries, mechanic screen show tutorial tells you that when there is not enough light you are losing sanity health ,  and a flashlight beacon light so it tells you to grab it, it is next to you. (Mechanic trigger boxes if the character passes one of those collision boxes an event will fire).  (Mechanic the flashlight uses batteries that can be drained so you can reload by finding the batteries in the house, they are randomed in random positions, you are using points and when the game starts you are spawning those points with random items that can be batteries or sanity regain pills).  Mechanic sanity can drop when trigger a scare or random event also can drop when there is not enough light in the area.