To myself, when I first know the word 僵尸, it's from Hong Kong horror movies. It is usually referred to Chinese zombies - they are waring Qing dinasty government dressings, with the whole iron like stiff body that they cannot bend over the arms or legs. So they jump and jump very far strangely... And they all have long nails which is very scary... During late 80s and early 90s last century, there was a wave of Hong Kong horror movie about Chinese zombies. As for the zombies eating brains, we have a word 丧尸。