Episodic memory: The stories of our lives

An episodic memory is a stored representation of something you have experienced (Tulving, 1972) - for example, a documentary you have viewed on television, a marketing field trip to a local shopping mall to view store window displays, or a conversation with a friend about today's lunch. Episodic memories are rich in detail, much of which may be of no great significance. Episodes are associated with a particular time and place. In fact, we often use time and place to help us recall the details of a specific event we have experienced. For example, during a quiz, a student may attempt to recall last Thursday's lecture to locate information relevant to a particular question. Internally, the information within an episode is also organized sequentially much in the way a story has a beginning, middle and end.

It is interesting to note that there are positive and negative uses of episodic representations. In certain situations, teachers may not want students to store their academic experiences as episodes. They want students to think carefully about educational experiences such as lectures to understand or abstract important ideas rather than to store the verbatim comments. In other circumstances, however, teachers want students to use experiences from their lives either to discover principles or as a route a richer understanding of principles that may be presented without much embellishment in a book or lecture. Students sometimes question the relevance of what is being learned for the "real world" without acknowledging that they have countless stored experiences from the "real world" that might now be better understood if these stored experiences were interpreted as examples of newly learned principles or concepts. Encouraging the connections is the trick. For example, a psychology instructor might ask, "Did your mother ever tell you that you couldn't have dessert until you finished your vegetables? Why do you think she said that? This happens to be a common parenting tactic that would serve as an example of something called the "Premack Principle". This principle proposes that a desirable activity can serve as a reinforcement for a less desirable activity. The point here is that the connection of a specific past experience and thinking about other experiences which may share common characteristics may help bring meaning to what else might be an abstract principle.

Some instructional strategies ask that educators think about stored experiences in still a different way. For examples, advocates of case-based learning, pointing to the problem-solving behavior of individuals in professions such as medicine, claim that decisions are often based on the recollection of "episodes" rather than abstract principles. According to this argument, when many physicians encounter a challenging case, their problem-solving behavior first involves the recollection of similar cases they have experienced and then an analysis of common and unique attributes in the case being considered. The educational implication of such observations has led to a greater emphasis on the accumulation and analysis of "cases" in the preparation of professionals for certain fields.

Personal reflection may demonstrate that life stories play a very important role in your own thinking and problem solving in applied settings. It is not just doctors and lawyers who solve problems in this manner. We all ask ourselves the question, "Has something like this happened to me before?" The recollection of what we or someone else did in a particular situation can be adapted as a solution to a new problem (McLellan, 1996). An essential point in understanding the significance of educational experiences is that experiences by themselves are not equivalent to knowledge. Much of what we present here is focused on this issue: How do teachers get students to create knowledge and not be satisfied with simply storing information? Students need to take an active role in working with the information they receive. There are different goals that this active learning might accomplish; for example:

• One goal might be to acquire principles, rules, concepts, or some other form of abstract knowledge by working with experiences or examples. In this case, learning tasks would be designed to help learners construct personally meaningful abstractions.
• A second learning goal might be to store personal experiences as episodes, but to also associate meaningful labels with these experiences. When experts recall personal experiences to assist in problem solving, it is clear that some type of organization is involved. A physician may recall cases based on criteria such as pneumonia in very young children, strange red rashes following a high fever, or an arrhythmic heartbeat in overweight, fifty-year-old males. This labeling system, which some researchers describe as indexing, is a very important part of what learners accomplish as they learn from cases (Edelson, 1998; Lesgold, 2001). Learning from cases might be described as processing experiences in such a way that the cases serve as useful personal examples of principles, rules, or concepts.

Perhaps one way to understand the immediate educational challenge is to recognize that both abstractions (declarative knowledge) and stored personal experiences (episodes) are necessary for understanding. Either component may be missing. It is quite conceivable that the concept mammal is overly narrow among individuals who have not been exposed to whales or dolphins. It is also possible that wide experiences with animal life would not result in an understanding of the abstraction, mammal. Apart from whether the components are present is the issue of whether the components are connected in meaningful ways (the network model of memory will be presented shortly).

Technology can play in important role in helping learners achieve these learning goals. Sometimes technology can provide experiences through simulations or video representations. In moving beyond exposure to new experiences, many of the tasks we emphasize here involve projects requiring learners to process information with the goal of constructing personal knowledge. This processing involves developing and storing personal abstractions and using these abstractions for indexing personal experiences. Technology may provide the means to engage learners with experiences (cases) in ways that are both practical and productive (Lesgold, 2001; Schank, 1998).