Interference: unique source of forgetting in working memory?

Journal of Experimental Psychology: Learning, Memory, and Cognition, 2008

The time-based resource-sharing model of working memory assumes that memory traces suffer from a time-related decay when attention is occupied by concurrent activities. Using complex continuous span tasks in which temporal parameters are carefully controlled, P. Barrouillet, S. Bernardin, S. Portrat, E. Vergauwe, & V. Camos (2007) recently provided evidence that any increase in time of the processing component of these tasks results in lower recall performance. However, K. Oberauer and R. Kliegl (2006) pointed out that, in this paradigm, increased processing times are accompanied by a corollary decrease of the remaining time during which attention is available to refresh memory traces. As a consequence, the main determinant of recall performance in complex span tasks would not be the duration of attentional capture inducing time-related decay, as Barrouillet et al. (2007) claimed, but the time available to repair memory traces, and thus would be compatible with an interference account of forgetting. The authors demonstrate here that even when the time available to refresh memory traces is kept constant, increasing the processing time still results in poorer recall, confirming that time-related decay is the source of forgetting within working memory.

Journal of Experimental Psychology: Learning, Memory, and Cognition, 2011

The sources of forgetting in working memory are a matter of intense debate: is there a time-related decay of memory traces or is forgetting uniquely due to representation-based interference? In a previous study, we claimed to have provided evidence supporting the temporal decay hypothesis (Portrat, Barrouillet, & Camos, 2008). However, reanalyzing our data, Lewandowsky and Oberauer (2009) demonstrated that they do not provide compelling evidence for temporal decay, and suggested a class of alternative models favoring a representation-based interference account. In this article, we develop from the most recent proposals made by these authors two of the most plausible extensions of these alternative models. We show that none of these extensions can account for recent findings related to between-domain working memory performance, and that both lead to predictions that are contradicted by new empirical evidence. Finally, we show that recent studies that have been claimed to rule out the temporal decay hypothesis do not resist close scrutiny. We conclude that the TBRS model remains the most parsimonious way to account for forgetting and restoration of memory traces in working memory.

Acta Psychologica, 1990

Trends in Cognitive Sciences, 2009

Many models of short-term memory (STM) ascribe an important role to temporal decay and forgetting because of the passage of time alone. We argue against decay as the primary form of forgetting from STM, and suggest that new experimental methodologies and recent models provide new perspectives on the old issue of the causes of forgetting. We show that several classic sources of evidence for time-based forgetting can be reinterpreted in terms of an interference-based view, and that new experiments provide compelling evidence against decay. We conclude that progress requires moving beyond demonstrations of qualitative effects and focusing instead on testing quantitative predictions of models.

Journal of Mathematical Psychology, 2009

A common belief in the study of short-term memory is that the verbal trace decays around two seconds after it is encoded. This belief is typically assumed to follow from the finding that in immediate serial recall, the time required to rapidly articulate a span-length list is around two seconds. Empirically, this belief is in opposition to a broad set of findings across a number of domains that establish mean decay times to be longer than two seconds. Theoretically, the available computational and mathematical models of immediate serial recall do not address this issue directly, because they typically rely on other mechanisms in addition to decay to account for forgetting. As such, they may show that decay times can be longer than two seconds, but they fail to show that they cannot be as short as two seconds. We address the issue directly and set a lower bound on mean trace decay times, even under the limiting assumption that all forgetting is due to trace decay. We do this by presenting a simple item-based model of trace decay that allows us to estimate values of mean trace duration. For a set of words whose span-length lists can be rapidly articulated in about two seconds, the model offers a conservative estimate for their mean decay times of around four seconds. Both the experimental and theoretical evidence show that items in verbal working memory decay considerably slower than the two-second decay hypothesis claims.

Journal of Memory and Language, 2008

This article presents four experiments that tested predictions of SOB (Serial Order in a Box), an interference-based theory of short-term memory. Central to SOB is the concept of novelty-sensitive encoding, which holds that items are encoded to the extent that they differ from already-encoded information. On the additional assumption that distractors are encoded into memory in the same manner as list items, the theory predicts differential effects of interfering activity based on the similarity structure of distractors. Consistent with predictions, three experiments showed that overt articulation of distractors in between recalls of list items did not affect forgetting when the same distractor was repeated multiple times, whereas forgetting was observed if several different distractors were articulated within the same time span. A fourth experiment showed that the absence of forgetting with repeated articulations of the same item was not due to compensatory attentional refreshing of memory traces. The data support the notion that forgetting from short-term memory arises from interference and are difficult to reconcile with temporal decay.

2013

The sources of forgetting in working memory are a matter of intense debate: is there a time-related decay of memory traces or is forgetting uniquely due to representation-based interference? In a previous study, we claimed to have provided evidence supporting the temporal decay hypothesis (Portrat, Barrouillet, & Camos, 2008). However, reanalyzing our data, Lewandowsky and Oberauer (2009) demonstrated that they do not provide compelling evidence for temporal decay, and suggested a class of alternative models favoring a representation-based interference account. In this article, we develop from the most recent proposals made by these authors two of the most plausible extensions of these alternative hal-00798381, version 1- 8 Mar 2013 models. We show that none of these extensions can account for recent findings related to between-domain working memory performance, and that both lead to predictions that are contradicted by new empirical evidence. Finally, we show that recent studies th...

Psychonomic Bulletin & Review, 2012

Although forgetting in the short term is a ubiquitous phenomenon, its exact causes remain undecided. The aim of the present study was to test the temporal decay hypothesis according to which memory traces fade away with time when attention is diverted by concurrent activities.

Memory & Cognition, 2010

Four effects-the word length effect, the irrelevant speech effect, the acoustic confusion effect, and the concurrent articulation effect-have played a prominent role in the development of influential theories of immediate memory. Indeed, accounting for these four findings was one of the motivations for creating the phonological loop component of working memory (Baddeley, 1992), and these effects are seen as key data that computational models of short-term memory must account for (Lewandowsky & Farrell, 2008). Despite the numerous studies examining these phenomena, very few studies have examined them using backward recall. To that end, one purpose of the four experiments reported here was to assess whether the four benchmark effects of working memory are observable with backward recall. A second purpose was to test the predictions of two models of memory: Despite their many differences, both the primacy model (Page & Norris, 1998) and the feature model (Nairne, 1990) predict that all four effects should be observed with backward recall. Empirical Review Word length effect. The word length effect refers to the finding that lists of short (i.e., one-syllable) words are recalled better than otherwise comparable lists of longer (i.e., multisyllabic) words (Baddeley, Thomson, & Buchan an, 1975; for a review, see Neath & Surprenant, 2003). The standard paradigm is forward immediate serial recall, but the word length effect is also observable with reconstruction of order (Nairne, Neath, & Serra, 1997), serial recognition (Baddeley, Chincotta, Stafford, & Turk, 2002), free recall (Watkins, 1972), single-item probe recall (Avons, Wright, & Pammer, 1994), and complex span (Tehan, Hendry, & Kocinski, 2001) tests. However, only a small number of studies have examined whether the effect is observable with backward recall. Cowan et al. (1992, Experiment 3) had subjects recall lists of short and long words in both a forward and a backward order, and recall direction was not known until test. However, a straightforward interpretation of the results is difficult, since word length was manipulated within a list (i.e., the first half of the list was short words, the second half long words), and since the lists had five items, there were not equal numbers of short and long items per list. Moreover, the stimuli used have since been shown to be atypical (see,

Psychonomic Bulletin & Review, 2004