The Generation Effect
The generation effect refers to the long-term benefit of generating an answer, solution or procedure versus the relatively poor retention seen in being presented with it. The retrieval of learned information, therefore, is a more effective strategy than, say, re-reading the material because of the cognitive effort required. One study, for example, found that using cues (such as the first two letters of a learned item or an anagram) resulted in better retention than re-reading the item. The generation effect can also be described as a form of deep processing (see levels of processing effect, below).
The Testing Effect
The testing effect (or retrieval practice) describes how the regular retrieval of learned information (perhaps by quizzing, testing or questioning) strengthens the capacity to retain and more effectively recall the learned information.
The Spacing Effect
The spacing effect (often described as distributed practice) is where information is better retained in long-term memory if it is presented over time, rather than in massed form. Spacing exploits the way in which the cognitive architecture best encodes information into long-term memory by both allowing some information to be forgotten and, consequently, forcing us to employ greater cognitive effort to recall it.
The Production Effect
The production effect refers to the phenomenon whereby saying a word out loud makes it more likely to be recalled later. A less effective method involves the mouthing of word without any outward vocalisation. Some studies have found a 15% to 20% increase in recall of words that have been said aloud.
Levels of Processing Effect (or Levels of Processing Model)
Levels of processing states that effective recall is determined by the depth at which the information has been processed. Processing can be shallow (based in the appearance or the sound of the information) or deep (based on meaning and enhanced through elaboration rehearsal (main article on memory models).