RETRIEVAL PRACTICE Take a moment to answer each of these Learning Objective Questions (repeated here from within this section). Then click the 'show answer' button to check your answers. Research suggests that trying to answer these questions on your own will improve your long-term retention (McDaniel et al., 2009).

Memory is learning that has persisted over time, through the encoding, storage, and retrieval of information. Evidence of memory may be recalling information, recognizing it, or relearning it more easily on a later attempt.

Psychologists use memory models to think and communicate about memory. Information-processing models involve three processes: encoding, storage, and retrieval. Our agile brain processes many things simultaneously (some of them unconsciously) by means of parallel processing. The connectionism information-processing model focuses on this multitrack processing, viewing memories as products of interconnected neural networks. The three processing stages in the Atkinson-Shiffrin model are sensory memory, short-term memory, and long-term memory. This model has since been updated to include two important concepts: (1) working memory, to stress the active processing occurring in the second memory stage; and (2) automatic processing, to address the processing of information outside of conscious awareness.

The human brain processes information on dual tracks, consciously and unconsciously. Explicit (declarative) memories—our conscious memories of facts and experiences—form through effortful processing, which requires conscious effort and attention. Implicit (nondeclarative) memories—of skills and classically conditioned associations—happen without our awareness, through automatic processing.

In addition to skills and classically conditioned associations, we automatically process incidental information about space, time, and frequency.

Sensory memory feeds some information into working memory for active processing there. An iconic memory is a very brief (a few tenths of a second) sensory memory of visual stimuli; an echoic memory is a three- or four-second sensory memory of auditory stimuli.

Short-term memory capacity is about seven items, plus or minus two, but this information disappears from memory quickly without rehearsal. Working memory capacity varies, depending on age, intelligence level, and other factors.

Effective effortful processing strategies include chunking, mnemonics, hierarchies, and distributed practice sessions. The testing effect is enhanced memory after consciously retrieving, rather than simply rereading, information.

Depth of processing affects long-term retention. In shallow processing, we encode words based on their structure or appearance. Retention is best when we use deep processing, encoding words based on their meaning. We also more easily remember material that is personally meaningful—the self-reference effect.