The benefit of deep processing is that it gives a lasting memory compared to a shallow processing in where the memories or thoughts do not last. The cognitive processing of one's stimulus is it's meaningful properties rather than the perceptual one.
Deep processing involves elaboration rehearsal which is a memory technique that involves thinking about the meaning of the term to be remembered, as opposed to simply repeating the word to yourself over and over. It also involves a more meaningful analysis (e.g. images, thinking, associations etc.) of information and leads to better recall. For example, giving words a meaning or linking them with previous knowledge.
