An image forming apparatus that is capable of performing post-processing so as to ensure that sheets on which images are formed and inserted sheets are aligned in orientation when performing sheet insertion processing and post-processing in combination. The BD-ROM playback apparatus includes a playback control engine for playing an AVClip belonging to one title, and a module manager controlling branching between a plurality of titles, and a BD-J module for executing at least one application. Pain markers and markers of degenerating disc include markers of neuronal, vascular, immune and matrix elements.