Does expanded retrieval produce benefits over equal-interval spacing? Explorations of spacing effects in healthy aging and early stage Alzheimer's disease

Three experiments explored different schedules of retrieval practice in young adults, older adults, and individuals with dementia of the Alzheimer type. In each experiment, an initial acquisition phase was presented in which participants studied or attempted to retrieve response words to cues, followed by a later cued-recall test. Experiment 1 produced a benefit of expanded retrieval over equal-interval retrieval during acquisition, but this benefit was lost in final cued recall. In Experiments 2 and 3, participants received corrective feedback during acquisition and modified spacing schedules. There was again no evidence of a difference between expanded and equal-interval conditions in final cued recall. Discussion focuses on the potential benefits and costs of expanded retrieval on a theoretical and applied level.     

Does interword spacing influence lexical processing in Chinese reading?

This study investigated how inserting spaces between Chinese words affected word recognition in Chinese reading. Eye movements of Chinese readers were recorded in a sentence reading task where high- and low-frequency target words were presented in both the spaced and normally unspaced texts. We found that fixation durations on target words were shorter in the high- than low-frequency conditions, and shorter in the spaced than unspaced conditions. The survival analysis revealed that interword spacing advanced the temporal onset of word frequency effects relative to the normally unspaced condition. However, inconsistent with the findings in English reading, there was no interaction between word frequency and interword spacing on all fixation duration measures, and the Bayes factor analyses also favoured the hypothesis of null interaction. These data suggest that interword spacing facilitates visual rather than lexical processing in Chinese reading, and thus improves our understanding on the roles of interword spacing across different writing systems.     

Development of sensitivity to spacing versus feature changes in pictures of houses: Evidence for slow development of a general spacing detection mechanism?

Adults are expert at recognizing faces, in part because of exquisite sensitivity to the spacing of facial features. Children are poorer than adults at recognizing facial identity and less sensitive to spacing differences. Here we examined the specificity of the immaturity by comparing the ability of 8-year-olds, 14-year-olds, and adults to discriminate houses differing in the spacing between features versus those differing in the shape of the features themselves. By 8 years of age, children were more accurate for discriminations involving the feature set compared with the spacing set, and the difference in accuracy compared with adults was greater for the spacing set than for the feature set. Importantly, when sets were matched in difficulty for adults, this greater immaturity on the spacing set than on the feature set remained. The results suggest that, at least by age 8, immaturities in sensitivity to the spacing of features may be related to immaturities in general perceptual mechanisms rather than face-specific mechanisms.     

What is the role of affect in the spacing effect?

In Experiments 1 and 2, after studying a list containing connotatively neutral words that were presented once or were presented at various spacing intervals, subjects either attempted free recall or made affective judgments of the study-list targets along a pleasant/unpleasant dimension. Spacing effects occurred in recall, and massed items were judged to be more unpleasantthan once-presented and spaced words. In the third experiment, subjects studied homogeneous lists composed of either connotatively good words or connotativelybad ones. Spacing effects were absent in the recall of both types of words because massed-practice words were recalled at a high level, one that was about the same as that for spaced-practice words. Affective judgments were unrelated to presentation condition, and both good and bad massed words were judged to be positive in affect. Although the data suggest that different study conditions can lead to different affective reactions, the results are moot with regard to the relationship between affect and the magnitude of spacing effects.     

A deeper analysis of the spacing effect after “deep” encoding

The most common encoding strategies used by participants in word list studies include rehearsal and using the story mnemonic. Previous studies have suggested that with a rote-rehearsal strategy, mixed lists lead people to borrow rehearsal time from massed items and to give it to spaced items. Using rehearse-aloud methodologies, we demonstrated in Experiment 1 that the borrowing effect does not occur in the story mnemonic. However, the rates of rehearsal of individual items provided a good prediction of their subsequent recall rates, with spaced items being rehearsed more often in both mixed and pure lists. In Experiment 2, we demonstrated that creating "story links" between items enhanced recall, but it did not affect the magnitude of the spacing effect. These results suggest that a massed-item deficit in encoding may underlie the spacing effect in the story mnemonic.     

Same—differentjudgments of multiletter strings: Insensitivity to positional bias and spacing

Several recent studies of multiletter matching have included pairs of strings that have-the-same letters in different positions (rearranged pairs). The task can be defined such that these rearranged pairs are correctly classified asdifferent (i.e., subjects respond “same” only if the strings have the same letters in the same positions—the order task) or assame (i.e., subjects respond “same” if the strings have the same letters regardless of their positions—the item task). The order task produces left-to-right serial-position effects, whereas the item task produces U-shaped serial position effects. Because these differences suggest that subjects may be able to exert strategic control over the comparison process, two sets of experiments were designed to test whether or not subjects can change the relative weightings devoted to the respective serial positions. In Experiments 1 and 2, the probability that a mismatch occurred in the different positions was manipulated. In Experiments 3 and 4, the physical spacing between letters, as well as whether or not the spaces were filled with neutral noise characters, was varied. None of the manipulations had much influence on the serial-position effects. Thus, the distinct serial-position effects for the order and item tasks apparently are mandatory and not due-to-any voluntary-comparison strategy.     

Is temporal spacing of tests helpful even when it inflates error rates?

The occurrence of errors is often thought to impede associative learning. This was tested in 2 studies, each of which involved 2 sessions. In Session 1, subjects learned foreign vocabulary (Experiment 1) or obscure English words (Experiment 2) and received 2 tests (each with corrective feedback) separated by a variable lag. Greater lags drastically reduced performance on the 2nd test. However, they dramatically improved performance in a Session-2 test given 1 day (Experiment 1) or 1 week later (Experiment 2). This pattern held even for items that elicited errors on the 1st test of Day 1. Evidently, the benefit of spacing overwhelms any possible harmful effect of producing errors. The results have clear and nonobvious implications for computer-aided instruction.     

Learning concepts and categories: is spacing the "enemy of induction"?

Inductive learning -- that is, learning a new concept or category by observing exemplars -- happens constantly, for example, when a baby learns a new word or a doctor classifies x-rays. What influence does the spacing of exemplars have on induction? Compared with massing, spacing enhances long-term recall, but we expected spacing to hamper induction by making the commonalities that define a concept or category less apparent. We asked participants to study multiple paintings by different artists, with a given artist's paintings presented consecutively (massed) or interleaved with other artists' paintings (spaced). We then tested induction by asking participants to indicate which studied artist (Experiments 1a and 1b) or whether any studied artist (Experiment 2) painted each of a series of new paintings. Surprisingly, induction profited from spacing, even though massing apparently created a sense of fluent learning: Participants rated massing as more effective than spacing, even after their own test performance had demonstrated the opposite.     

The spacing effect in older and younger adults: does context matter?

Age-related memory change has been a topic of much investigation in recent years, including spacing benefits and reliance on contextual cues. We manipulated the spacing schedule and the context of learning and observed the effects on long-term recall ability in healthy older and younger adults. After learning Swahili–English word pairs, half practiced immediately (massed) and half practiced 24 h later (spaced) either in the same room or a different room (context) from the initial session. A final recall test 10 days after the practice session occurred in the same room as the first session. Participants in the spaced condition remembered more than those in the massed condition 10 days later. Younger adults remembered more word pairs than older adult participants. Context change eliminated the spacing benefit for both age groups.     

Retrieval practice over the long term: Should spacing be expanding or equal-interval?

If multiple opportunities are available to review to-be-learned material, should a review occur soon after initial study and recur at progressively expanding intervals, or should the reviews occur at equal intervals? Landauer and Bjork (1978) argued for the superiority of expanding intervals, whereas more recent research has often failed to find any advantage. However, these prior studies have generally compared expanding versus equal-interval training within a single session, and have assessed effects only upon a single final test. We argue that a more generally important goal would be to maintain high average performance over a considerable period of training. For the learning of foreign vocabulary spread over four weeks, we found that expanding retrieval practice (i.e., sessions separated by increasing numbers of days) produced recall equivalent to that from equal-interval practice on a final test given eight weeks after training. However, the expanding schedule yielded much higher average recallability over the whole training period.     

Children's memory for complex autobiographical events: Does spacing of repeated instances matter?

Often, when children testify in court they do so as victims of a repeated offence and must report details of an instance of the offence. One factor that may influence children's ability to succeed in this task concerns the temporal distance between presentations of the repeated event. Indeed, there is a substantial amount of literature on the “spacing effect” that suggests this may be the case. In the current research, we examined the effect of temporal spacing on memory reports for complex autobiographical events. Children participated in one or four play sessions presented at different intervals. Later, children were suggestively questioned, and then participated in a memory test. Superior recall of distributed events (a spacing effect) was found when the delay to test was 1?day (Experiment 1) but there was little evidence for a spacing effect when the delay was 1 week (Experiment 2). Implications for understanding children's recall of repeated autobiographical events are discussed.     

Children's memory for complex autobiographical events: does spacing of repeated instances matter?

Often, when children testify in court they do so as victims of a repeated offence and must report details of an instance of the offence. One factor that may influence children's ability to succeed in this task concerns the temporal distance between presentations of the repeated event. Indeed, there is a substantial amount of literature on the "spacing effect" that suggests this may be the case. In the current research, we examined the effect of temporal spacing on memory reports for complex autobiographical events. Children participated in one or four play sessions presented at different intervals. Later, children were suggestively questioned, and then participated in a memory test. Superior recall of distributed events (a spacing effect) was found when the delay to test was 1 day (Experiment 1) but there was little evidence for a spacing effect when the delay was 1 week (Experiment 2). Implications for understanding children's recall of repeated autobiographical events are discussed.     

The spacing effect in young children’s free recall: Support for automatic-process explanations

The effect of spacing repetitions on children's free recall was investigated in two experiments. In Experiment 1, both 4-year-old children and 7-year-old children exhibited a spacing effect in free recall, and the magnitude of the effect did not change with age. In Experiment 2, free recall was examined as a function of spacing, age (3 years old vs. 4 years old) and presentation rate (1 vs. 2 vs. 5 sec per stimulus). A spacing effect was obtained that did not differ as a function of age or presentation rate. Of particular interest was the fact that 3-year-olds exhibited a strong spacing effect even when stimuli were presented at a very rapid 1-sec rate. The results support the hypothesis that fundamental memory mechanisms that operate relatively automatically are sufficient to produce a spacing effect in free recall.     

Why does picture-plane inversion sometimes dissociate perception of features and spacing in faces, and sometimes not? Toward a new theory of holistic processing

Classically, it has been presumed that picture-plane inversion primarily reduces sensitivity to spacing/configural information in faces (distance between location of the major features) and has little effect on sensitivity to local feature information (e.g., eye shape or color). Here, we review 22 published studies relevant to this claim. Data show that the feature inversion effect varied substantially across studies as a function of the following factors: whether the feature change was shape only or included color/brightness, the number of faces in the stimulus set, and whether the feature was in facial context. For shape-only changes in facial context, feature inversion effects were as large as typical spacing inversion effects. Small feature inversion effects occurred only when a task could be efficiently solved by visual-processing areas outside whole-face coding. The results argue that holistic/configural processing for upright faces integrates exact feature shape and spacing between blobs. We describe two plausible approaches to this process.     

Are two spaces better than one? The effect of spacing following periods and commas during reading

The most recent edition of the American Psychological Association (APA) Manual states that two spaces should follow the punctuation at the end of a sentence. This is in contrast to the one-space requirement from previous editions. However, to date, there has been no empirical support for either convention. In the current study, participants performed (1) a typing task to assess spacing usage and (2) an eye-tracking experiment to assess the effect that punctuation spacing has on reading performance. Although comprehension was not affected by punctuation spacing, the eye movement record suggested that initial processing of the text was facilitated when periods were followed by two spaces, supporting the change made to the APA Manual. Individuals’ typing usage also influenced these effects such that those who use two spaces following a period showed the greatest overall facilitation from reading with two spaces.     

Does mediator use contribute to the spacing effect for cued recall? Critical tests of the mediator hypothesis

When study is spaced across sessions (versus massed within a single session), final performance is greater after spacing. This spacing effect may have multiple causes, and according to the mediator hypothesis, part of the effect can be explained by the use of mediator-based strategies. This hypothesis proposes that when study is spaced across sessions, rather than massed within a session, more mediators will be generated that are longer lasting and hence more mediators will be available to support criterion recall. In two experiments, participants were randomly assigned to study paired associates using either a spaced or massed schedule. They reported strategy use for each item during study trials and during the final test. Consistent with the mediator hypothesis, participants who had spaced (as compared to massed) practice reported using more mediators on the final test. This use of effective mediators also statistically accounted for some – but not all of – the spacing effect on final performance.     

A short‐term perceptual priming account of spacing effects in explicit cued‐memory tasks for unfamiliar stimuli

Memory for repeated items improves when presentations are spaced during study. This effect is found in explicit memory tasks using different types of material, different experimental paradigms, and in different subject populations. Two experiments are described where the spacing effect was assessed on a yes/no recognition memory task using words and nonwords as targets. The main results showed that changing the font between repeated occurrences of targets at study did not affect the spacing effect for words, even under shallow encoding conditions, but effectively removed the spacing effect with nonwords. In both experiments, the font manipulation was made between subjects, ruling out explanations in terms of differential attention to particular font conditions. These results provide further support for short‐term perceptual priming accounts of the spacing effect: Semantically‐based repetition priming affects memory for words; perceptual priming mechanisms affect memory for nonwords.     

Who,What, When,Where, How,and Mostly Why?

SUMMARY

The death of a client by suicide was very emotionally destabilizing to this therapist. She worked hard to distance herself personally from the pain at first and at the same time she found herself overfocused on the “psychological autopsy.” She had difficulty accepting new clients and wanted to withdraw from a meaningful appointment to a state advisory committee. Only when she was able to identify with the client's pain and realize how that pain touched her own history of loss was she able to grieve productively. She realized that gender was relevant in her identification with the victim and in sorting out each of their histories of loss.