If you were wondering why Silent Hill: Book of Memories was named that, well it is because that is the exact premise of the story. In a video released by Konami, Konami producer Tomm Hulett explains that the PlayStation Vita title Silent Hill: Book of Memories will have players “receive a strange book. When you open it, you see your entire life story written on those pages. All your memories.”
Apparently after you go back into your memories you can rewrite them and alter reality. The trailer also shows off some very early gameplay footage directly from Konami. It seems the game will be similar to a four player brawler more than a standard Silent Hill game from this footage, though perhaps things will look better in the future as the game is developed more.