at an advantage over massed items by the additional encoding of contextual information. Thus, the second occurrence of an item in a list reminds the observer of the previous occurrence of that same item and of its previous contextual features. Different contextual information is encoded with each presentation, whereas for massed items, the difference in context is relatively small. More retrieval cues, then, are encoded with spaced learning, which in turn leads to improved recall.

Deficient processing