this feedback you don't have accountability of the individual neurons all you can say is that whatever I'm doing here is wrong and whatever I'm doing here is right so I'm gonna do more of the right things now in back propagation it is very different right in back propagation what you'll do is you'll have your feedback here let's say that's negative 1 and then you do a reverse computation so the forward computation in this case was this weighted sum of this layer now usually layer wise reverse computation which