ABSTRACT
Introduction
Failures of prospective memory are common in everyday life, yet not widely studied in the laboratory. Prospective memory requires the individual to remember to perform a future event. Einstein and McDaniel (1990) have suggested that prospective memory actually involves two components: remembering that something needs to be remembered (the prospective component), and remembering the information itself (the retrospective component). They also make the distinction between event-based prospective memory, which requires some action when an external event takes place, and time-based prospective memory, in which action is required after a specified time interval has passed. Time-based remembering is hypothesized to rely on self-initiated memory processes because no external event acts as a cue for remembering. The individual must continuously shift attentional resources between other tasks and the monitoring of time. This "multi-tasking" aspect of time-based prospective memory may be especially vulnerable to problems with planning and the reallocation of attentional resources, and suggests a possible role in these tasks for the frontal lobes. In Cockburn's (1995) case study of a frontal lobe patient, it was found that the patient could remember to perform actions when they were embedded in an ongoing activity, but had great trouble when the task involved suspension of one activity in order to begin another (contextual shift) (see Kvavilashvili, 1992).
