Fergus I. M. Craik University of Toronto
On a number of occasions Endel Tulving has stressed the central role of events and episodes in an analysis of memory. In Tulving's ( 1984) words, "The basic units of perceived time are events. An event is something that occurs in a particular place at a particular time. The closely related term 'episode' refers to an event that is part of an ongoing series of events" (p. 229). Also, "The basic unit of the conceptual analysis of episodic memory is an act of remembering that begins with an event perceived by the remembered, and ends with recollective experience" (p. 229). Typically, a remembered event or episode consists of some focal elements (e.g., objects or actions) framed within a spatiotemporal context. The act of encoding serves to integrate the representations of the event with its context so that later presentation of part of the context (recall) or part of the focal event (recognition) can lead to redintegration of the entire encoded episode.
The integration of event and context is thus of crucial importance in the understanding of memory processes, yet very little is known about the factors that provide the mental 'glue' to hold elements together. The perceptual principles described by the Gestalt psychologists represent one attempt to grapple with the issue, as does other work in perception seeking to explain how a series of discrete visual fixations is transformed into a continuous whole (e.g., Kolers, 1973). In memory theory, the work on organization (e.g., Mandler, 1967; Miller , 1956; Tulving, 1962) is also relevant to some extent.
In this chapter I discuss two lines of work that bear on the problem; both are somewhat preliminary, but the ideas and findings are presented nonetheless in the hope that they draw attention to the issues and perhaps trigger debate.