Age dissociates recency and lag recency effects in free recall

The temporal relations among word-list items exert a powerful influence on episodic memory retrieval. Two experiments were conducted with younger and older adults in which the age-related recall deficit was examined by using a decomposition method to the serial position curve, partitioning performance into (a) the probability of first recall, illustrating the recency effect, and (b) the conditional response probability, illustrating the lag recency effect (M. W. Howard & M. J. Kahana, 1999). Although the older adults initiated recall in the same manner in both immediate and delayed free recall, temporal proximity of study items (contiguity) exerted a much weaker influence on recall transitions in older adults. This finding suggests that an associative deficit may be an important contributor to older adults' well-known impairment in free recall.     

Influences of environmental context on the recency effect in free recall

A total of 208 undergraduate participants incidentally encoded a list of seven pairs of familiar words in two experiments. A 30-sec calculation task was imposed before and after each pair was encoded. Participants received a free recall test 24 h (Experiment 1) or 10 min (Experiment 2) after the encoding session, under conditions in which the original environmental context was reinstated or not. The environmental context was manipulated in terms of the combination of the physical features of the room, the subsidiary task conducted, the experimenter (Experiment 1), or background music (Experiment 2). A recency effect appeared when the original environmental context was reinstated in both experiments, even though the IPI/RI ratio was too small to produce recency effects according to the ratio rule. The results imply that the environmental context should be taken into account for the recency effect.     

A three-component analysis of the modality effect in single-trial free recall

Johann-Wolfgang-Goethe Unversität, Frankfurt am Main, West-Germany In single-trial free recall a superiority of acoustical over visual presentation has been observed in the recency part of the serial position curve. The rehearsal-buffer model by Atkinson and Shiffrin (1968) was modified to distinguish between three different explanations that are discussed in the literature. The application of the model allowed some of the parameters to vary across modes of presentation while other parameters were held constant. A model assuming either a precategorical acoustical storage or additional processing for visually presented items gives a better account of the results than does a model derived from a two-store hypothesis.     

Moving and memorizing: Motor planning modulates the recency effect in serial and free recall

Motor planning has generally been studied in situations where participants carry out physical actions without a particular purpose. Yet in everyday life physical actions are usually carried out for higher-order goals. We asked whether two previously discovered motor planning phenomena - the end-state comfort effect and motor hysteresis - would hold up if the actions were carried out in the service of higher-order goals. The higher-order goal we chose to study was memorization. By focusing on memorization, we asked not only how and whether motor planning is affected by the need to memorize, but also how memory performance might depend on the cognitive demands of motor planning. We asked university-student participants to retrieve cups from a column of drawers and memorize as many letters as possible from the inside of the cups. The drawers were opened either in a random order (Experiment 1) or in a regular order (Experiments 2 and 3). The end-state comfort effect and motor hysteresis were replicated in these conditions, indicating that the effects hold up when physical actions are carried out for the sake of a higher-order goal. Surprisingly, one of the most reliable effects in memory research was eliminated, namely, the tendency of recent items to be recalled better than earlier items - the recency effect. This outcome was not an artifact of memory being uniformly poor, because the tendency of initial items to be recalled better than later items - the primacy effect - was obtained. Elimination of the recency effect was not due to the requirement that participants recall items in their correct order, for the recency effect was also eliminated when the items could be recalled in any order (Experiment 3). These and other aspects of the results support recent claims for tighter links between perceptual-motor control and intellectual (symbolic) processing than have been assumed in the past.     

Modality dependency of loss of recency in free recall

Summary Four experiments were carried out in which the probability of free recall of words as a function of serial position within lists was examined. The lists were presented either auditorily or visually, with subjects either silent or engaged in irrelevant articulation, and with recall either immediate or after an auditory or visual intervening task. The results provide evidence for the presence of modality-specific capacity limitations in primary memory, and also indicate that forgetting may occur in a last-in, first-out manner.The authors thank Nancy Chenier for assistance with Experiment 4, and two anonymous reviewers for their helpful comments. Research has been supported by the SRC (MM) and MRC (GVJ). Requests for offprints should be sent to Maryanne Martin, University of Oxford, Department of Experimental Psychology, South Parks Road, Oxford OX1 3UD, England.     

A context-based theory of recency and contiguity in free recall

The authors present a new model of free recall on the basis of M. W. Howard and M. J. Kahana's temporal context model and M. Usher and J. L. McClelland's leaky-accumulator decision model. In this model, contextual drift gives rise to both short-term and long-term recency effects, and contextual retrieval gives rise to short-term and long-term contiguity effects. Recall decisions are controlled by a race between competitive leaky accumulators. The model captures the dynamics of immediate, delayed, and continual distractor free recall, demonstrating that dissociations between short- and long-term recency can naturally arise from a model in which an internal contextual state is used as the sole cue for retrieval across time scales.     

Phonological similarity and enhanced auditory recency in longer-term free recall

The effect of phonological similarity amongst list items on the modality effect was investigated in free recall with distraction activity interpolated before and after each list word. In Experiment 1 the distractor activity involved counting backward silently mouthing each number, and the modality effect was drastically attenuated by high similarity. This outcome is comparable with that found in immediate recall, and it is consistent with an echoic memory interpretation. In Experiment 2 the same backward-counting task was performed with each number being vocalized, and the modality effect was unaffected by phonological similarity. This outcome leads to the stronger conclusion that, under those conditions at least, the modality effect cannot be echoic. Implications of these findings for general theoretical accounts of the modality effect are discussed.     

Empirical and theoretical limits on lag recency in free recall

One widely accepted empirical regularity in free recall holds that when people successively transition from report of one list item to another, they prefer transitions across short lags (e.g., by reporting items from adjacent serial positions) to transitions involving large lags. This regularity has provided crucial support for the temporal context model (TCM), a model of the evolution of temporal context in episodic memory (Howard & Kahana, 2002a). We report a reanalysis of 14 data sets that shows that, contrary to the presumed preference for short lags, people often produce transitions with larger lags during recall. We show that these data cannot be accommodated by the TCM. We furthermore show that existing applications of the model have, for mathematical convenience, introduced assumptions that have circumvented its core principle of context evolution. When we instantiated the TCM as it was actually described, with a gradually evolving context, we found that its behavior qualitatively departed from that of the version currently implemented, but that the model was still unable to capture the nature of transitions in free recall. We conclude that the TCM requires further modification and development before it can explain the data that constitute its main source of support. Supplementary materials relevant to this article can be downloaded from the Psychonomic Society’s Norms, Stimuli, and Data Archive, www.psychonomic .org/archive.     

The influence of word frequency on recency effects in directed free recall

Leading theoretical explanations of recency effects are designed to explain the reported absence of a word frequency effect on recall of words from recency serial positions. The present study used a directed free-recall procedure (J. J. Dalezman, 1976) and manipulated the frequency composition of the word lists (pure and mixed). Overall, with pure lists, a greater proportion of high-frequency (HF) words were recalled than low-frequency (LF) words, and with mixed lists, a greater proportion of LF words were recalled than HF words. Of importance, this recall advantage for one frequency over the other as a function of list composition was evident across the last three serial positions, indicating an influence of word frequency on recency effects that is dependent on the frequency composition of the lists. These results challenge one of the major assumptions on which several theories of recency effects have been based.     

The effects of interference tasks on recency in the free recall of action events

Summary Lists of verbal instructions were read aloud and each was enacted either by the subject (SPTs) or by the experimenter (EPTs). In Experiment 1 free recall was made of lists of SPTs and EPTs either immediately after presentation, after an empty 20-s delay interval, or after a 20-s delay interval filled with backward counting. The recall of recency items was unaffected by the empty delay interval, but was somewhat reduced by the counting task. In Experiment 2 free recall was made of lists of SPTs and EPTs either immediately after presentation or after a delay that was filled with a single SPT or a single EPT, 20 s in length. The recency effect evident in the immediate-recall condition was virtually wiped out in the delay conditions, irrespective of whether the delay task matched those in the free-recall list or not. These results are discussed in terms of the mnemonic similarity of the two types of action event.     

Primacy and recency in primed free association and associative cued recall

Two experiments compared the serial positions of primed words in an implicit free association test with words recalled in a cued recall test. In both tests, weakly or strongly related word pairs were studied, and the first words of each pair formed the test cues. In the implicit test, weakly related words pairs showed primacy and extended recency effects but strongly related word pairs did not. In the explicit test, both weakly and strongly related word pairs showed primacy and extended recency effects. These functional dissociations between implicit and explicit memory tests indicate that strongly related word pairs are encoded together because they have unitized memory representations that function as integrated units without requiring any additional associative links to be made, but that an additional system or process is required to strengthen weakly related word pairs during encoding. In addition, a further additional system or process is accessed by explicit retrieval.     

Inverting the modality effect in serial recall

Differences in recall ability between immediate serial recall of auditorily and visually presented verbal material have traditionally been considered restricted to the end of to-be-recalled lists, the recency section of the serial position curve (e.g., Crowder & Morton, 1969). Later studies showed that--under certain circumstances--differences in recall between the two modalities can be observed across the whole of the list (Frankish, 1985). However in all these studies the advantage observed is for recall of material presented in the auditorily modality. Six separate conditions across four experiments demonstrate that a visual advantage can be obtained with serial recall if participants are required to recall the list in two distinct sections using serial recall. Judged on a list-wide basis, the visual advantage is of equivalent size to the auditory advantage of the classical modality effect. The results demonstrate that differences in representation of auditory and visual verbal material in short-term memory persist beyond lexical and phonological categorization and are problematic for current theories of the modality effect.     

Primacy and recency effects in immediate free recall of sequences of spatial positions

This study evaluated the serial position curve based on free recall of spatial position sequences. To evaluate the memory processes underlying spatial recall, some manipulations were introduced by varying the length of spatial sequences (Exp. 1) and modifying the presentation rate of individual positions (Exp. 2). A primacy effect emerged for all sequence lengths, while a recency effect was evident only in the longer sequences. Moreover, slowing the presentation rate increased the magnitude of the primacy effect and abolished the recency effect. The main novelty of the present results is represented by the finding that better recall of early items in a sequence of spatial positions does not depend on the task requirement of an ordered recall but it can also be observed in a free recall paradigm.     

Recency and the modality effect in immediate ordered recall

In immediate ordered recall, recency is the improved recall of the last item of a presentation, and the modality effect is the advantage for an acoustic presentation over a subvocalized visual presentation, primarily occurring at the last serial position. Experiment 1 tested grouped presentations. There was a modality effect for the first item of the last group, even though that item was at the third-to-last or fourth-to-last serial position. In Experiment 2, for vocalized presentations of syllables ending in a, recency was larger for staccato speech than legato speech; for subvocalized presentations, there was a substantial recency for the legato style. In Experiment 3, recency was larger for a set of syllables ending in ATE than for a set of syllables ending in AME. These results suggest that recency cannot be explained by the existence of a fixed-capacity store, auxiliary to the auditory short-term store, that retains only some types of presentations. It is suggested instead that recency might reflect an auxiliary method of using the information in the auditory short-term store.     

The basis and implications of the restoration of a recency effect in immediate serial recall

When a spoken presentation of a supra-span sequence of to-be-remembered (TBR) items is followed immediately by a similarly-spoken non-TBR item (stimulus suffix) the typical salience of the terminal item in recall is almost destroyed. However, Salter (1975) observed restoration of salience when pre-terminal and terminal TBR items differed in category membership. Five experiments are reported which aimed to clarify the basis and locus of Salter's effect. Survival of salience for the heterogeneous item was found under the following conditions: with the occurrence of the item unpredictable from trial-to-trial (Experiment I); with enforced processing of the suffix (Experiment II); with performance of a secondary task during list presentation (Experiment III); with the requirement to retain both the location and identity of the item (Experiment IV); and with the item as the terminal member of a non-suffixed visual list (Experiment V). It is argued that the effect has a postcategorical locus, and that its origin is not in better registration (mediated by selective attention), but, rather, in the enhancement of retrieval (mediated by access to distinctive information encoded during presentation). It is suggested that the latter hypothesis may have wide application in accounting for many kinds of salience.     

The auditory recency advantage in longer term free recall is not enhanced by recalling prerecency items first

Gardiner and Gregg (1979) showed that in a free-recall paradigm in which each list word is embedded in a continuous stream of subject-vocalized distractor activity, recency recall was greater when the words were presented auditorily rather than visually. The experiment described here showed that this auditory advantage persisted even when list and distractor items were both spoken at a controlled pace by the experimenter, and that it was little influenced by instructions to give priority in recall either to the beginning or to the end of the list. These results strengthen the conclusion that this effect cannot be accommodated by any echoic memory theory and, because the effect was not enhanced when prerecency items were recalled first, demonstrate an additional difference between it and the somewhat similar auditory advantage found in immediate recall.     

Order of recall,output interference,and the modality effect

Summary In free recall, the order of recall following auditory and visual presentation differs; it tends to be forward for auditory but backward for visual. The first two experiments examined to what extent this difference in output order could account for the modality effect (i.e., a superior retention of auditorily as opposed to visually presented words). Order of recall was manipulated using postcued (Experiment 1) and precued (Experiment 2) procedures. Whereas the modality effect was unaffected with postcueing it was reduced to approximately half its size with precueing. It was concluded from these two studies that although output order cannot explain the whole modality effect, it does seem to play an important role for part of the effect in some situations. Experiments 3 and 4 used a mixed-mode and a probed recall procedure, respectively, to examine the role of output interference in modality experiments. The data suggested that output interference effects were non-monotonic; they were greater for visual than for auditory early in recall, but apparently no different later in recall. The two-store hypotheses (Murdock and Walker, 1969) was elaborated slightly to account for these results.This research was supported by Research Grants APA 146 from the National Research Council of Canada and OMHF 164 from the Ontario Mental Health Foundation. We would like to thank Doris Glavnov and Janet Metcalfe for help with the data analyses.     

An adjacency effect in free recall

An adjacency effect was demonstrated at a high level of significance in the free recall, by 123 subjects, of a list of 40 high-frequency nouns presented in varying order on successive trials. The phenomenon referred to as the adjacency effect consists of the fact that when a subject is given repeated trials of study and free recall of a list of words (always presented in a different order), the probability of recalling a given item is greater when the item is presented temporally adjacent to an item which is already learned (as evidenced by recall on the previous trial) than when the item stands temporally between other items which are not yet learned. The enhancement of recall is greater when the item is presented between two previously learned items. The implications of the adjacency effect for verbal learning theory, particularly for the serial-position effect in serial learning and the concepts of interference and neural consolidation, are discussed.