If you woke up tomorrow with no memories, would you even know who you were? Memories and identity are closely related—so related, in fact that one of the main reasons for R's zombie identity crisis is that he has no memories of the past. It's not as bad as being a zombie version of Memento, but it's close. Warm Bodies turns classic zombie mythology on its head by making this loss of memory a zombie's main motivation for braaaaaiiinns. They're not eating brains because they're hungry; they're eating brains because it gives them a jolt of memory. And to a zombie, memories are life.