Secondary memory and very rapid forgetting

Short-term retention of words as a function of encoding depth

The traditional short- and long-term storage view of information processing and the levels-of-processing view both discuss the forgetting of information over time. In the traditional stage view, there is loss of at least poorly encoded information across several seconds when the information cannot be rehearsed (e.g., Ricker et al., 2020, Learning, Memory, and Cognition, 46, 60-76). In the levels-of-processing approach, information that is encoded in a shallow manner is lost more quickly over time than deeply-encoded information (Craik & Lockhart, 1972, Journal of Verbal Learning and Verbal Behavior, 11, 671-684.). Previous studies of the depth of encoding, however, have mostly been conducted using delayed tests, so there are few studies directly comparing the rate of forgetting over time for information as a function of different depths of encoding. We manipulated the level of processing with immediate recall in a modified Brown-Peterson task. An effect of the level of processing was robust, but evidence of forgetting across retention intervals was not always observed. When encoding time was curtailed (in Experiments 3 and 4), we found main effects of both the level of processing and the retention interval, but no interaction between the two variables. The results suggest that the depth-of-encoding effect may occur during the initial encoding of items, but without differential forgetting within the range of retention intervals that we examined (0-18 s), in contrast to the suggestion by Craik and Lockhart. Further work is needed to determine whether the depth-of-processing effect would grow over longer intervals.

Short-Term Forgetting of Order under Conditions of Reduced Interference

Three experiments examined the short-term retention of order in a modified Brown-Peterson task. Our intent was to examine the loss of order memory, unconfounded by item memory, under conditions in which interference from prior trials is kept low. In previous work on the short-term forgetting of order, experimenters have tended to repeat the same items across trials or to draw from a restricted set; in our experiments, we changed the to-be-recalled items from trial to trial and used reconstruction as the retention measure. In all three experiments, very little forgetting was obtained across retention intervals that have traditionally produced dramatic and systematic loss. Our results are reminiscent of those obtained in the Brown Peterson task when performance is assessed after only the first experimental trial.

Processing strategies and secondary memory in very rapid forgetting

When a memory test is unexpected, recall performance is quite poor at retention intervals as short as 2-4 seconds. Orienting tasks that change encoding conditions are known to affect forgetting in such "very rapid forgetting" paradigms where people are misled to believe that recall will not be required. We evaluated the hypothesis that differences in forgetting among orienting tasks are attributable to contributions of secondary memory during encoding in two experiments. In Experiment 1, short-term recall performance was inversely related to task demands during encoding, although long-term memory performance was not. Task demands were assessed by making the duration of stimulus presentation dependent on the time required to perform three different orienting tasks. In Experiment 2, we compared performance of that variable-length stimulus presentation to the fixed-length presentation used in most prior research. The results suggested that additional encoding or rehearsal time does not have an appreciable impact on short-term performance. Thus, differences in forgetting appeared to be a function of the contribution of secondary memory rather than a function of the time available to engage in primary memory rehearsal strategies.

VERBAL LEARNING AND MEMORY: Does the Modal Model Still Work?

This chapter focuses on recent research concerning verbal learning and memory. A prominent guiding framework for research on this topic over the past three decades has been the modal model of memory, which postulates distinct sensory, primary, and secondary memory stores. Although this model continues to be popular, it has fostered much debate concerning its validity and specifically the need for its three separate memory stores. The chapter reviews research supporting and research contradicting the modal model, as well as alternative modern frameworks. Extensions of the modal model are discussed, including the search of associative memory model, the perturbation model, precategorical acoustic store, and permastore. Alternative approaches are discussed including working memory, conceptual short-term memory, long-term working memory, short-term activation and attention, processing streams, the feature model, distinctiveness, and procedural reinstatement.

Is there really very rapid forgetting from primary memory? The role of expectancy and item importance in short-term recall

In two experiments, subjects recalled one of two letter segments following a digit-filled retention interval. In Experiment 1, recall expectancy was manipulated by using precues that correctly informed or misinformed subjects concerning which letter segment would be tested for recall. In Experiment 2, item importance was varied by precuing one segment as important but requiring that the uncued segment be recalled first. Recall performance was very low under conditions of low expectancy and low segment importance, but the slopes of the retention functions did not demonstrate more rapid forgetting than under standard conditions. The previous observations of very rapid forgetting from primary memory may be a function of an elevated initial recall level in the earlier studies. Our retention functions were compared with predictions of the Estes perturbation model. The findings suggested that when secondary memory processes were reduced, forgetting order information from primary memory occurred at the same rate as that estimated on the basis of previous studies using the standard distractor task.

Time-sharing in the continuous distractor paradigm: a reexamination of the long-term recency effect

Long-term recency effects observed in the continuous distractor paradigm are often taken as evidence against the short-term store account of recency effects. In the present study, three experiments examined the function of time-sharing process in the continuous distractor paradigm. In the first two experiments, the effect of distractor difficulty on long-term recency was investigated with easy and hard distractor tasks. Distractor difficulty was manipulated in the recency portion and in the retention interval of a nine-word list and a hard distractor task eliminated long-term recency effects. In Exp. 3, distractor difficulty was manipulated across the first and the second halves of the retention interval. Long-term recency effects were larger if the first half of the retention interval contained an easy distractor task and the second half a hard task than if the order was hard-easy. These results indicate that subjects maintain recent items in short-term store and then transfer them to a long-term store by the time-sharing process during a distraction period. Long-term recency effects to a large extent depend on this time-sharing process.