Predicting free recalls

This article reports some calculations on free-recall data from B. Murdock and J. Metcalfe (1978), with vocal rehearsal during the presentation of a list. Given the sequence of vocalizations, with the stimuli inserted in their proper places, it is possible to predict the subsequent sequence of recalls--the predictions taking the form of a probability distribution over all possible such sequences. The predictions are parameter free. This article looks at (a) the accuracy of those predictions and how that accuracy can be validated, (b) the principles on which the predictive algorithm is based, and (c) the limits to predictability. Some implications for the understanding of free recall are spelled out.     

Spoken and written recall of visual narratives

This study is concerned with the effects of recall mode on memory for visual narratives. Subjects were shown a series of slides depicting an auto-pedestrian accident. They were then asked to free-recall all information they could remember. Half were asked to speak their free recalls. The other half were asked to write down their free recalls. The results showed that spoken recall was more accurate. These data were compared with previous studies using visual and textual narratives.     

Testing the Idea of Distinct Storage Mechanisms in Memory

This paper sets out quantitative foundations for testing the idea that memory is served by two distinct storage mechanisms, a short-term and a separate long-term store, using data from the single-trial free-recall experiment by Murdock and Okada (1970). In single-trial free recall one can observe which word is recalled next and how long that recall takes, but that is all. So justification for two separate stores must turn either on the probabilities of recall, or on the latencies, for particular serial positions in the stimulus list. (a) Nearly one-third of all recalls after the first are successors (Word n+1 immediately following recall of Word n). So recall is dominated, not by absolute serial position (as a short-term store would require), but by position relative to the preceding recall. (b) To a first approximation, all first recalls have the same latency distribution except for Word 1. A common latency distribution is compatible with a single store. An explanation is offered why Word 1 should take longer, in which Word 1 is the second retrieval from a common store. The idea of two separate stores appears to lack experimental support.     

Introductory Comments

Three groups of informants—two in California, one in Atlanta—recalled their experiences of the 1989 Loma Prieta earthquake shortly after the event and again 1 1/2 years later. The Californians' recalls of their own earthquake experiences were virtually perfect. Even their recalls of hearing the news of an earthquake-related event were very good: much higher than Atlantan recalls of hearing about the quake itself. Atlantans who had relatives in the affected area remembered significantly more than those who did not. These data show that personal involvement in the quake led to greatly improved recall, but do not show why. Many Californian informants reported low levels of stress/arousal during the event; arousal ratings were not significantly correlated with recall. The authors suggest that repeated narrative rehearsals may have played an important role.     

What can we learn about immediate memory from the development of children's free recall?

We ask the question: Which aspects of immediate memory performance improve with age? In two studies, we reexamine the widely held view that primary memory capacity estimates derived from children's immediate free recall are age invariant. This was done by assessing children's immediate free-recall accuracy while also measuring the order in which they elected to recall items (Experiment 1) and by encouraging children to begin free recall with items from towards the end of the presented list (Experiment 2). Across samples aged between 5 and 8 years we replicated the previously reported age-related changes in free-recall serial position functions when aggregated across all trials of the standard task, including an absence of age differences in the recency portion of this curve. However, we also show that this does not reflect the fact that primary memory capacity is constant across age. Instead, when we incorporate order of report information, clear age differences are evident in the recall of list-final items that are output at the start of a participant's response. In addition, the total amount that individuals recalled varied little across different types of free-recall tasks. These findings have clear implications for the use of immediate free recall as a means of providing potential indices of primary memory capacity and in the study of the development of immediate memory.     

A Distributed Representation of Temporal Context

The principles of recency and contiguity are two cornerstones of the theoretical and empirical analysis of human memory. Recency has been alternatively explained by mechanisms of decay, displacement, and retroactive interference. Another account of recency is based on the idea of variable context (Estes, 1955; Mensink & Raaijmakers, 1989). Such notions are typically cast in terms of a randomly fluctuating population of elements reflective of subtle changes in the environment or in the subjects' mental state. This random context view has recently been incorporated into distributed and neural network memory models (Murdock, 1997; Murdock, Smith, & Bai, 2001). Here we propose an alternative model. Rather than being driven by random fluctuations, this formulation, the temporal context model (TCM), uses retrieval of prior contextual states to drive contextual drift. In TCM, retrieved context is an inherently asymmetric retrieval cue. This allows the model to provide a principled explanation of the widespread advantage for forward recalls in free and serial recall. Modeling data from single-trial free recall, we demonstrate that TCM can simultaneously explain recency and contiguity effects across time scales.     

Recognition failures and free-recall failures: Implications for the relation between recall and recognition

Experiments showing that in cued recall subjects can recall words that they had previously failed to recognize have been taken to refute generate-recognize theories of recall, for those theories predict that recall is dependent on recognition. None of these experiments, however, has provided an appropriate test of Bahrick’s (1970, 1979) generate-recognize theory, which explicitly refers to words that are accessible to cued recall but not to free recall, that is, tofree-recall failures. When the experimental procedure was modified so as to provide tests of this theory, no evidence was found of any greater dependency between recall and recognition of free-recall failures than between recall and recognition overall. Free-recall failures do not, therefore, constitute any exception to many previous experimental findings that conform with the Tulving-Wiseman law, and so the account offered by Bahrick’s generate-recognize theory may be rejected. The results also suggest an explanation for some other conflicting evidence on whether recall and recognition are dependent or independent.     

Age-related deficits in free recall: The role of rehearsal

Age-related deficits have been consistently observed in free recall. Recent accounts of episodic memory suggest that these deficits could result from differential patterns of rehearsal. In the present study, 20 young and 20 older adults (mean ages 21 and 72 years, respectively) were presented with lists of 20 words for immediate free recall using the overt rehearsal methodology. The young outperformed the older adults at all serial positions. There were significant age-related differences in the patterns of overt rehearsals: Young adults rehearsed a greater number of different words than did older adults, they rehearsed words to more recent serial positions, and their rehearsals were more widely distributed throughout the list. Consistent with a recency-based account of episodic memory, age deficits in free recall are largely attributable to age differences in the recency, frequency, and distribution of rehearsals.     

A maximum likelihood hierarchical disaggregate model for predicting choices of individuals

The absence of operational disaggregate lexicographic decision models and Tversky's observation that choice behavior is often inconsistent, hierarchical, and context dependent motivate the development of a maximum likelihood hierarchical (MLH) choice model. This new disaggregate choice model requires few assumptions and accommodates the three aspects of choice behavior noted by A. Tversky (1972, Journal of Mathematical Psychology, 9, 341–367). The model has its foundation in a prototype model developed by the authors. Unlike the deterministic prototype, however, MLH is a probabilistic model which generates maximum likelihood estimators of the aggregate “cutoff values.” The model is formulated as a concave programming problem whose solutions are therefore globally optimal. Finally, the model is applied to data from three separate studies where it is demonstrated to have superior performance over the prototype model in its predictive performance.     

Benefits of testing for nontested information: Retrieval-induced facilitation of episodically bound material

Testing is a powerful means to boost the retention of information. The extent to which the benefits of testing generalize to nontested information, however, is not clear. In three experiments, we found that completing cued-recall tests for a subset of studied materials enhanced retention for the specific information tested, as well as for associated, nontested information during later free-recall testing. In Experiment 1, this generalized benefit was revealed for lists of category–exemplar pairs. Experiment 2 extended the effect to unrelated words, suggesting that retrieval can enhance later free recall of nontested information that is bound solely through episodic context. In Experiment 3, we manipulated the format of the final test and found facilitation in free-recall, but not in cued-recall, testing. The results suggest that testing may facilitate later free recall in part by enhancing access to information that is present during a prior temporal or list context. More generally, these findings suggest that retrieval-induced facilitation extends to a broader range of conditions than has previously been suggested, and they further motivate the adoption of testing as a practical and effective learning tool.     

Memorability as a measure of processing: a unit analysis of prose and list learning

The percentage of subjects recalling each unit in a list or prose passage is considered as a dependent measure. When the same units are recalled in different tasks, processing is assumed to be the same; when different units are recalled, processing is assumed to be different. Two collections of memory tasks are presented, one for lists and one for prose. The relations found in these two collections are supported by an extensive reanalysis of the existing prose memory literature. The same set of words were learned by 13 different groups of subjects under 13 different conditions. Included were intentional free-recall tasks, incidental free recall following lexical decision, and incidental free recall following ratings of orthographic distinctiveness and emotionality. Although the nine free-recall tasks varied widely with regard to the amount of recall, the relative probability of recall for the words was very similar among the tasks. Imagery encoding and recognition produced relative probabilities of recall that were different from each other and from the free-recall tasks. Similar results were obtained with a prose passage. A story was learned by 13 different groups of subjects under 13 different conditions. Eight free-recall tasks, which varied with respect to incidental or intentional learning, retention interval, and the age of the subjects, produced similar relative probabilities of recall, whereas recognition and prompted recall produced relative probabilities of recall that were different from each other and from the free-recall tasks. A review of the prose literature was undertaken to test the generality of these results. Analysis of variance is the most common statistical procedure in this literature. If the relative probability of recall of units varied across conditions, a units by condition interaction would be expected. For the 12 studies that manipulated retention interval, an average of 21% of the variance was accounted for by the main effect of retention interval, 17% by the main effect of units, and only 2% by the retention interval by units interaction. Similarly, for the 12 studies that varied the age of the subjects, 6% of the variance was accounted for by the main effect of age, 32% by the main effect of units, and only 1% by the interaction of age by units.(ABSTRACT TRUNCATED AT 400 WORDS)     

The Perception of Mechanical Vibration: III. The Frequency Function

Three studies of male and female undergraduates examined the effects of incidental orienting tasks on the free recall of concrete nouns. In Experiments 1 (between-Ss design N = 53) and 2 (within-Ss design N = 54) semantic orienting tasks resulted in recall that was equal to or higher than recall following intentional learning. Nonsemantic orienting tasks produced poorest recall. In Experiment 3 (N = 59), Ss performed a word recognition task between two free-recall trials. The target and distractor words were either acoustically, orthographically, or semantically related or were unrelated to each other. On the second free-recall trial, recall was highest for target words that had been paired with semantically related distractors. The results of the three experiments add to the growing support for a levels-of-processing model of memory.     

Limitations to the spacing effect: demonstration of an inverted u-shaped relationship between interrepetition spacing and free recall

The spacing effect refers to the finding that memory for repeated items improves when the interrepetition interval increases. To explain the spacing effect in free-recall tasks, a two-factor model has been put forward that combines mechanisms of contextual variability and study-phase retrieval (e.g., Raaijmakers, 2003; Verkoeijen, Rikers, & Schmidt, 2004). An important, yet untested, implication of this model is that free recall of repetitions should follow an inverted u-shaped relationship with interrepetition spacing. To demonstrate the suggested relationship an experiment was conducted. Participants studied a word list, consisting of items repeated at different interrepetition intervals, either under incidental or under intentional learn instructions. Subsequently, participants received a free-recall test. The results revealed an inverted u-shaped relationship between free recall and interrepetition spacing in both the incidental-learning condition and the intentional-learning condition. Moreover, for intentionally learned repetitions, the maximum free-recall performance was located at a longer interrepetition interval than for incidentally learned repetitions. These findings are interpreted in terms of the two-factor model of spacing effects in free-recall tasks.     

Issues with the SIMPLE model: comment on Brown, Neath, and Chater (2007)

SIMPLE (G. D. A. Brown, I. Neath, & N. Chater, 2007) attempts to explain data from serial recall and free recall in the same theoretical framework. While it can fit the free-recall serial-position curves that are the cornerstone of the 2-store buffer model, it does not address 2 classic issues in short-term memory research: similarity effects and presentation-rate effects. Similarity effects in free recall led to important work on organization in free recall, whereas similarity effects in serial recall led to the phonological basis of short-term memory. Presentation-rate effects operate quite differently in free and serial recall. The model also does not consider recall order effects or interresponse times in free recall, which may be problematic.     

A study of retrieval processes in action memory for school-aged children: the impact of recall period and difficulty on action memory

ABSTRACT

Research in action memory for adults has shown that enacted encoding is not only retrieved more frequently but is also faster in comparison to verbal encoding. The aim of this study was to investigate retrieval processes in terms of recall period and recall difficulty for different encoding conditions in school-aged children (8-, 10-, 12-, 14-years old). The participants studied verbal tasks, subject-performed tasks and experimenter-performed tasks, and received immediate and final free-recall tests. The results revealed that older children not only outperformed younger children in terms of accuracy but also outpaced them in all recall periods. Moreover, recalls of subject-performed tasks and experimenter-performed tasks were better and faster compared with verbal encoding on both types of recall test, by increasing throughout the recall periods. These results are discussed in terms of memory strategies and information processing methods. Pedagogic implications for the use of action memory in children's learning are also considered.     

Free recall measures of short-term store: Are rehearsal and order of recall data necessary?

Several investigators have claimed that immediate free recall is a composite of output from two different storage systems—a short-term store (STS) and a long-term store (LTS). Free recall data and measures of STS were evaluated by having subjects report their rehearsals while lists of words were presented at a rate of one word every 1.25, 2.50, or 5.00 sec. The results support the conclusions that (a) arranging recall as a function of where an item was presented, rather than where it was rehearsed, is inappropriate to discussions of STS and LTS, and (b) computing measures of STS without both rehearsal and order of recall data yields a biased estimate of STS.

     

Holographic and trace strength models of rehearsal effects in the item recognition task

Two models are described that are capable of generating latency predictions in the item recognition task based on the sequence and timing of rehearsals. It is shown that equal positive and negative slopes are possible when the average number of rehearsals per item increases with list length but that when no rehearsal occurs the positive slope is predicted to be substantially steeper than the negative. Serial position effects are also analyzed for the various rehearsal strategies seen when subjects are asked to rehearse out loud.     

Recency-sensitive retrieval processes in long-term free recall

In several experiments, each presentation of a to-be-remembered item in a free-recall list was both preceded and followed by a distracting activity and recall was delayed by an additional period of distracting activity. Pronounced long-term effects of recency were obtained, the standard short-term memory interpretation of recency effects in free recall notwithstanding. The results are interpreted as reflecting retrieval processes that are obscured by procedural characteristics of typical free-recall experiments.     

Rehearsal in immediate serial recall

We report for the first time overt rehearsal data in immediate serial recall (ISR) undertaken at three presentation rates (1, 2.5, and 5 sec/word). Two groups of participants saw lists of six words for ISR and were required either to engage in overt rehearsal or to remain silent after reading aloud the word list during its presentation. Typical ISR serial position effects were obtained for both groups, and recall increased with slower rates. When participants rehearsed, they tended to do so in a cumulative forward order up to Serial Position 4, after which the amount of rehearsal decreased substantially. There were similarities between rehearsal and recall data: Both broke down toward the end of longer sequences, and there were strong positive correlations between the maximum sequence of participants' rehearsals and their ISR performance. We interpret these data as suggesting that similar mechanisms underpin both rehearsal and recall in ISR.     

Retroactive inhibition as a function of similarity of meaning in free-recall learning

Summary Retroactive inhibition in free-recall learning was measured under six degrees of meaningful similarity: zero, low, low-medium, medium, medium-high, and high. For each degree of similarity, an experimental and a control group of 20 Ss each learned a list of 20 unrelated adjectives through three cycles of alternate study and unpaced free recall. Immediately thereafter, the experimental group learned a second list of 20 adjectives, while the control group rested. Finally, a single recall trial was administered to both groups to measure first-list retention. The results have revealed a relationship which is at variance with the relationships observed in both serial and paired-associate learning but conforms to the curvilinear function earlier formulated by Skaggs and Robinson. Fresh arguments are offered in defence of the Skaggs-Robinson hypothesis.