Each talent's card is represented by an image which when selected in gameplay by either numbered keys or mouse, then alters the mouse cursor to a small representation of that image. The border that surrounds that particular cursor is an indication of the success you will experience in using that talent. When you run out of either health or sanity, the bubbles have this really placid-death look to them. The maps were a bit small for me, and a tad redundant. You can replenish your sanity and health by the available tubes of each placed throughout the maps.
Movement is a key factor in survival.
You have to be on the constant move to refill your sanity and health. Most of my trouble with movement, came from the camera views. You start in an overhead view at a distance, however, you can change camera views to behind the person, zoom in and out, etc. I never felt I had the right camera view angle. I tried to use most of the 16 available talents to see how each one worked, and when it was best to use them.