How do I edit only the part of photo that I've cropped?

I didn't have this issue before, but now when I crop an image and then go to edit, it does not show the cropped image, only the original. That is, in edit mode, it reverts back to the original photo dimensions. How do I edit only the cropped are of the photo? Do I have to save the cropped area now?

Lightroom version: 4.0 X64

[question moved to LR Desktop by administrator]