A new experimental paradigm to evaluate the role of working memory in prospective memory

Background: Recently, several neuroscientific researches have been interested in investigating the role, functions and relation between prospective memory (PM) and working memory (WM), observing whether these two mechanisms use shared cognitive resources or they are partially independent [1,2]. Although the existence of some standardized tests for PM evaluation, there are few paradigms for its analysis. Materials and methods: This study aimed to examine the role of WM in PM in a sample of twenty-one healthy subjects. Participants were required to develop two different ongoing tasks together with a PM switching task. The first, arithmetic task, required a low WM load of cognitive resources; whereas, the second, PASAT test, demanded an high cognitive WM load. Prospective retrieval was administered from two different modalities: event-based and timebased. In event-based condition the PM recall was associated with an external cue (sound); while, in time-based condition the PM retrieval occured at a given time. Results: Findings demonstrated that PM was influenced by WM only during the development of complex tasks requiring an high cognitive load of WM and an active self-retrieval (time-pasat) of PM. Conclusions: These results demonstrate that WM and PM can be considered as distinct mechanisms at least when the prospective retrieval is associated with a cue (event-based conditions). Moreover, these findings highlight the complexity of PM such as high-level metacognitive function, which uses strategic and controlled processes for the coordination of future intentions. References: 1. R E Smith: The cost of remembering to remember in event-based prospective memory: investigating the capacity demands of delayed intention performance. J Exp Psychol Learn Mem Cogn, 2003, 29: 347-361. 2. R E Smith, U J Bayen: A multinomial model of event-based prospective memory. J Exp Psychol Learn Mem Cogn, 2004, 30: 756-777