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Abstract: The spacing effect is among the most widely replicated empirical phenomena in the learning sciences, and its relevance to education and training is readily apparent. Yet successful applications of spacing effect research to education and training is rare. Computational modeling can provide the crucial link between a century of accumulated experimental data on the spacing effect and the emerging interest in using that research to enable adaptive instruction. In this paper, we review relevant literature and identify 10 criteria for rigorously evaluating computational models of the spacing effect. Five relate to evaluating the theoretic adequacy of a model, and five relate to evaluating its application potential. We use these criteria to evaluate a novel computational model of the spacing effect called the Predictive Performance Equation (PPE). Predictive Performance Equation combines elements of earlier models of learning and memory including the General Performance Equation, Adaptive Control of Thought—Rational, and the New Theory of Disuse, giving rise to a novel computational account of the spacing effect that performs favorably across the complete sets of theoretic and applied criteria. We implemented two other previously published computational models of the spacing effect and compare them to PPE using the theoretic and applied criteria as guides. [ABSTRACT FROM AUTHOR]

Depletion of limited working memory resources may occur following extensive mental effort resulting in decreased performance compared to conditions requiring less extensive mental effort. This “depletion effect” can be incorporated into cognitive load theory that is concerned with using the properties of human cognitive architecture, especially working memory, when designing instruction. Two experiments were carried out on the spacing effect that occurs when learning that is spaced by temporal gaps between learning episodes is superior to identical, massed learning with no gaps between learning episodes. Using primary school students learning mathematics, it was found that students obtained lower scores on a working memory capacity test (Experiments 1 and 2) and higher ratings of cognitive load (Experiment 2) after massed than after spaced practice. The reduction in working memory capacity may be attributed to working memory resource depletion following the relatively prolonged mental effort associated with massed compared to spaced practice. An expansion of cognitive load theory to incorporate working memory resource depletion along with instructional design implications, including the spacing effect, is discussed. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Rosner, Lopez-Benitez, D'Angelo, Thomson, and Milliken (2017) reported a novel recognition memory effect using an immediate repetition method during the study phase. During each trial of an incidental study phase, participants named a target word that followed a prime word that had the same identity (repeated trials) or a different identity (not-repeated trials). Recognition in the following test phase was better for the not-repeated trials. In the present study, we examined the influence of prime encoding demands on this counterintuitive effect. In Experiment 1, we instructed 1 group to simply ignore the prime, as in the original study. A second group completed a divided attention task on prime presentation. Recognition memory was better for not-repeated than repeated words in both groups. In Experiment 2, encoding of the prime varied across 3 groups: 1 group named each prime, a second group counted the vowels in each prime, and a third group made a semantic discrimination for each prime. Recognition was better for repeated than for not-repeated words in the semantic group and did not differ across conditions for the other 2 groups. Finally, in Experiment 3, we assessed memory for not-repeated primes in addition to memory for targets (as in Experiments 1 and 2). The results confirmed that poor memory for the primes plays a significant role in producing the previously described effects. The results are discussed in relation to transient processing adaptations that affect memory encoding. [ABSTRACT FROM AUTHOR]

This study investigates the relation between review spacing and question format on student retention. Participants in an 8th grade Georgia Studies class reviewed previously learned material either in one sitting (massed review) or in multiple sessions (spaced review). Following the review, each participant answered questions either in multiple choice or short answer format. Subsequent to answering the questions, all students received feedback. One week following the completion of the reviews, students were given a post test. One month after the post test, students were given a final test. Pre-, post- and final tests were identical and no treatment occurred between the posttest and the final test. Correlational analyses of review spacing and question format suggest that spaced review is positively related to success on the posttest. There was no such finding related to massed review or question format on the posttest. Additionally, neither review spacing or question format had any correlational effect on the final test. Results suggest that spaced review is beneficial, but that the benefit is lost over time.

Recent accounts of the spacing effect have proposed molecular explanations that explain spacing over short, but not long timescales. In the first half of this paper, we review research on the spacing effect that has employed spaces of 24 h or more across skill-related tasks, language-related tasks and generalization for adults and children. Throughout this review, we distinguish between learning and retention by defining learning (or acquisition) as performance at the end of training and retention as performance after a delay period. Using this distinction, we find age- and task-related differences in the manifestation of the spacing effect over long timescales. In the second half of this paper, we discuss a reconsolidation account of the spacing effect. In particular, we review the evidence that suggests the spacing of repetitions influences the subsequent consolidation and reconsolidation processes; we explain how a reconsolidation account may explain the findings for learning; the inverted-U curve for retention; and compare the reconsolidation account with previous consolidation accounts of the spacing effect.

The declarative/procedural (DP) model posits that the learning, storage, and use of language critically depend on two learning and memory systems in the brain: declarative memory and procedural memory. Thus, on the basis of independent research on the memory systems, the model can generate specific and often novel predictions for language. Till now most such predictions and ensuing empirical work have been motivated by research on the neurocognition of the two memory systems. However, there is also a large literature on techniques that enhance learning and memory. The DP model provides a theoretical framework for predicting which techniques should extend to language learning, and in what circumstances they should apply. In order to lay the neurocognitive groundwork for these predictions, here we first summarize the neurocognitive fundamentals of the two memory systems and briefly lay out the resulting claims of the DP model for both first and second language. We then provide an overview of learning and memory enhancement techniques before focusing on two techniques – spaced repetition and retrieval practice – that have been linked to the memory systems. Next, we present specific predictions for how these techniques should enhance language learning, and review existing evidence, which suggests that they do indeed improve the learning of both first and second language. Finally, we discuss areas of future research and implications for second language pedagogy. [ABSTRACT FROM AUTHOR]

This paper presents the analytical methods of slope-stabilising piles using the three-dimensional (3-D) finite element (FE) analysis with the strength reduction method (SRM). This 3-D FE model is employed to overcome the limitations observed in two-dimensional (2-D) FE analysis. The solutions obtained from 3-D FE analyses are verified to be less conservative in this paper. The 3-D analysis is considered to be of particular importance to pile-slope problems. The soil that flows between piles cannot be taken account properly in the 2-D FE analysis. The method adopted in this paper can avoid the assumption of soil movement and the pressure distribution along the piles subjected to soil movement. The numerical analysis employs the Mohr–Coulomb failure criterion with the strength reduction technique for soil and an elastic member for piles. The spacing effect of the pile is considered in the 3-D model, the S/D (S: centre to centre, D: diameter of pile) ratio, equal to 4.0, is found to be equivalent to the single pile stabilisation. The middle portion of the slope is identified as the optimal location to place the piles. The proper length of the pile, which can be used to stabilise the slope, is also examined using 3-D FE analyses. It is concluded that L/H greater or equal 0.70 is recommended (L: pile length, H: slope height). The numerical analyses are conducted based on a coupled analysis, which simultaneously considers both the slope stability and the pile response. The failure mechanisms of the pile-slope system subjected to the pile locations, pile head conditions and pile length are each discussed. The contact pressure, shear force and moment along the piles are presented to illustrate the pile stabilising mechanism herein. [ABSTRACT FROM PUBLISHER]

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. [ABSTRACT FROM PUBLISHER]

This study investigated whether the use of a gamified mobile learning app influenced students' academic performance and boosted their engagement in the subject. Created to better engage students in lecture content, the app was used to deliver multiple-choice content-based quizzes directly to students' personal mobile devices post-lecture and pre-tutorial. After measuring the relationships between students' app usage and their engagement, retention and academic achievement in the subject, it is suggested that following the app's introduction, student retention rates and academic performance increased, and there was a positive correlation between students' scoring highly on the app and achieving higher academic grades. While the app's affordances for learning are promising, the causal relationship between the app usage and improved student outcomes requires further investigation. Conclusions made in the context of the wider scholarship of mobile app enhanced learning and applied game principles in HE. [ABSTRACT FROM AUTHOR]

The spacing effect refers to increased retention following learning instances that are spaced out in time compared with massed together in time. By one account, the advantages of spaced learning should be independent of task particulars and previous learning experiences given that spacing effects have been demonstrated in a variety of tasks across the lifespan. However, by another account, spaced learning should be affected by previous learning because past learning affects the memory and attention processes that form the crux of the spacing effect. The current study investigated whether individuals’ learning histories affect the role of spacing in category learning. We examined the effect of spacing on 24 2- to 3.5-year-old children’s learning of categories organized by properties to which children’s previous learning experiences have biased them to attend (i.e., shape) and properties to which children are less biased to attend (i.e., texture and color). Spaced presentations led to significantly better learning of shape categories, but not of texture or color categories, compared with massed presentations. In addition, generalized estimating equations analyses revealed positive relations between the size of children’s “shape-side” productive vocabularies and their shape category learning and between the size of children’s “against-the-system” productive vocabularies and their texture category learning. These results suggest that children’s attention to and memory for novel object categories are strongly related to their individual word-learning histories. Moreover, children’s learned attentional biases affected the types of categories for which spacing facilitated learning. These findings highlight the importance of considering how learners’ previous experiences may influence future learning. [ABSTRACT FROM AUTHOR]

• Memory-for-when judgments indicate when in a list an item first appeared and measure a kind of explicit temporal context memory. • Correct memory-for-when during study of items' second occurrence predicted items' final free recall on a later test. • Memory-for-when advantage was mainly driven by superior memory-for-when for items in the primacy region; other items showed no such benefit. • Explicit temporal context information probably doesn't cause the benefits of spaced repetition (though implicit context information or distinctiveness might) A number of temporal context-based theories of the spacing effect assume that temporal context is retrieved during repetitions, allowing better memory on a later test. Since associations in memory are often bidirectional, if we can use temporal context to recall an item, perhaps we can also use the item to explicitly recall its temporal context. If so, explicit memory-for-when during study would be a good predictor of later recall for repeated items. Experiment 1 appeared to be consistent with our predictions; items with memory-for-when during List 2 showed superior recall accuracy on a final free recall test. However, the effect was primarily driven by better memory-for-when in the primacy region. Experiment 2 used an incidental learning procedure during List 1 to reduce this confound since the primacy region is greatly attenuated in incidental learning. While the benefits of having memory-for-when persisted in Experiment 2, they were again attributable solely to the first few items on the list. The results suggest that explicit temporal context information is unlikely to underlie the benefits of spaced repetition. Either temporal context information is strengthened implicitly, our measures of context failed to capture the type of context used in spacing, or other mechanisms entirely produce the benefits of repetition. [ABSTRACT FROM AUTHOR]

This study investigated the effects of spacing on Chinese university students' L2 vocabulary learning. Sixty-seven junior students of a Science and Engineering College in China learnt English words by two types of spacing schedules, massed versus distributed , and the results of vocabulary learning were measured by accuracy and reaction rate. Results showed that the massed practice might be more effective than the distributed practice, particularly in accuracy for long-term retention. Further, it was found that the advantage of the massed practice was more obvious for receptive than for productive vocabulary knowledge. Finally, several suggestions are put forward on the learning and teaching of L2 vocabulary. [ABSTRACT FROM AUTHOR]

This study used a novel method to explore different schedules of spacing in young EFL learners. In doing so, we taught young EFL learners English–Farsi word pairs using different spacing schedules (massed vs. spaced). In the massed condition, learners studied five-word pairs in session one and five-other word pairs one week later. In the spaced condition, the learners studied 10-word pairs in session one and restudied them one week later. To amplify the benefits of spacing, we incorporated tests (with corrective feedback) into different schedules of spacing. In other words, EFL learners were instructed to test each other on their knowledge of the vocabulary and to give each other feedback. One week and five weeks later learners’ recall was assessed. The results showed that spaced practice produced better long-term retention than massed practice. To summarize, this study used spacing and retrieval practice techniques (with corrective feedback) to offer a pedagogically powerful approach for learning vocabulary.

Inductive category learning takes place across time. As such, it is not surprising that the sequence in which information is studied has an impact in what is learned and how efficient learning is. In this paper we review research on different learning sequences and how this impacts learning. We analyze different aspects of interleaved (frequent alternation between categories during study) and blocked study (infrequent alternation between categories during study) that might explain how and when one sequence of study results in improved learning. While these different sequences of study differ in the amount of temporal spacing and temporal juxtaposition between items of different categories, these aspects do not seem to account for the majority of the results available in the literature. However, differences in the type of category being studied and the duration of the retention interval between study and test may play an important role. We conclude that there is no single aspect that is able to account for all the evidence available. Understanding learning as a process of sequential comparisons in time and how different sequences fundamentally alter the statistics of this experience offers a promising framework for understanding sequencing effects in category learning. We use this framework to present novel predictions and hypotheses for future research on sequencing effects in inductive category learning.

Background. Rehabilitation practices can benefit from learning theories that have the potential illuminate the mechanism of action of conventional treatments. This study sought to establish an empirical foundation for a theory of learning for naming rehabilitation that is centered on retrieval practice, retrieval effort, and spacing. Psychological research has shown that retrieval practice (the act of retrieval from long-term memory) confers powerful and persistent learning, particularly when retrieval is effortful. The spacing effect refers to the ubiquitous advantage to learning when repeated training opportunities for individual items are distributed over time, rather than massed. In our prior work [1], we found that retrieval practice improved common object naming in people with chronic aphasia (PWA). Building on this, the goals of the present study were to: (1) investigate the impact of retrieval practice in a new performance domain (proper noun naming) in PWA by comparing retrieval practice training to an “errorless” condition where presentation of the name for repetition averted the need for retrieval from long-term memory; (2) determine whether greater retrieval effort during retrieval practice is associated with greater retention of training benefits; (3) determine whether spacing confers longer-lasting learning than massing. Methods. Four PWA with naming impairment named and gave familiarity ratings to a corpus of 700 pictures of proper noun entities twice over two weeks. For each participant, we selected items the participant knew recognized but could not consistently name for assignment into the conditions, with a minimum of 36 (max=72) items per condition across participants. The design involved a 2-level factor of type of training (retrieval practice versus errorless learning, i.e., repetition) and a factor of spacing, which included a massed condition (lag 1) and three spaced conditions (lags 5, 15, and 30). Lag corresponded to the number of training trials for other items that intervened between three presentations of an item for retrieval practice or repetition training. On a repetition trial, the name was presented (seen/heard) and the participant repeated the name at picture onset. On a naming trial, only the picture was presented. All trials ended in feedback (i.e., the name was presented). Primary outcome was naming performance on a retention test administered 1-day following training, with a 1-week follow-up test administered to measure persistence of the effects. Results & Conclusions. Mixed regression analyses revealed that the naming condition was associated with superior performance over repetition, observed both at the retention test (p=.001) and follow-up (p=.01; Figure 1, left panel). Also, spaced training conferred superior benefits compared to massed, both at retention test (p

The testing effect is the enhanced retention of learned information by individuals who have studied and completed a test over the material relative to individuals who have only studied the material. Although numerous laboratory studies and simulated classroom studies have provided evidence of the testing effect, data from a natural class setting with motivated students are scant. The present two-class quasi-experiment explored the external validity of the testing effect in the Introductory Psychology classroom. The control class studied assigned chapters from the textbook whereas the quiz class studied chapters and completed daily quizzes on those readings. Subsequently, both classes completed exams over this textbook information. The quiz class scored significantly higher than the control class on these test questions about the textbook information; these differences were significant both when the test questions were the same as the quiz questions and when they were new, related questions from the textbook. These data suggest the use of daily quizzes to embed the testing effect into the Introductory Psychology classroom can improve student learning. [ABSTRACT FROM AUTHOR]

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Mental practice (MP) is a promising adjuvant to physical practice that involves many of the same mechanisms and takes on many of the same properties as physical practice. This study compared efficacy of a 'massed' MP regimen versus a 'distributed' MP regimen on upper extremity (UE) motor impairment and functional limitation. Twenty-seven chronic stroke survivors were administered the UE section of the Fugl-Meyer (FM) and Action Research Arm Test (ARAT), followed by standardized physical practice and MP regimens. One group was administered 'massed' MP (60 min of MP during a single daily session) and a second group administered distributed MP (20 min of MP occurring three times/day). After intervention, changes in FM and ARAT scores of subjects in the distributed condition were significantly higher than those of subjects in the massed condition (FM 3.65, 95 % CI 0.82-6.49, p value = 0.01; ARAT 3.95, 95 % CI 1.24-6.67, p value = 0.006). Likewise, at POST 3, subjects in the distributed group showed significantly higher change in ARAT scores (ARAT 4.90, 95 % CI 0.57-9.22, p value = 0.03); the change in FM scores at POST 3 was 3.18 points higher among subjects in the distributed condition, but only approached significance (95 % CI −1.27 to 7.63, p value = 0.15). Results suggest that a distributed MP schedule is more efficacious in bringing about paretic UE changes than a massed practice schedule, especially in terms of reducing UE functional limitation. [ABSTRACT FROM AUTHOR]

Background: Distributing a fixed amount of teaching hours over a longer time period (spaced approach) may result in better learning than delivering the same amount of teaching within a shorter time (massed approach). While a spaced approach may provide more opportunities to elaborate the learning content, a massed approach allows for more economical utilisation of teaching facilities and to optimise time resources of faculty. Favourable effects of spacing have been demonstrated for postgraduate surgery training and for spacing intervals of weeks to months. It is however unknown, whether a spacing effect can also be observed for shorter intervals and in undergraduate medical education. Therefore, we aimed to evaluate the effect of a short spacing intervention within an undergraduate intensive course in emergency medicine (EM) on students' procedural knowledge. Methods: An EM intensive course of 26 teaching hours was delivered over either 4.5 days, or 3.0 days. After the course students' procedural knowledge was assessed by a specifically developed video-case based key-feature test (KF-test). Results: Data sets of 156 students (81.7 %, 191 students eligible) were analysed, 54 from the spaced, and 102 from the massed version. In the KF-test students from the spaced version reached a mean of 14.8 (SD 2.0) out of 22 points, compared to 13.7 (SD 2.0) in the massed version (p = .002). Effect size was moderate (Cohen's d: 0.558). Conclusion: A significant spacing effect was observable even for a short spacing interval in undergraduate medical education. This effect was only moderate and may be weighed against planning needs of faculty and teaching resources. [ABSTRACT FROM AUTHOR]

Learning and memory is commonly attributed to the modification of synaptic strengths in neuronal networks. More recent experiments have also revealed a major role of structural plasticity including elimination and regeneration of synapses, growth and retraction of dendritic spines, and remodeling of axons and dendrites. Here we work out the idea that one likely function of structural plasticity is to increase "effectual connectivity" in order to improve the capacity of sparsely connected networks to store Hebbian cell assemblies that are supposed to represent memories. For this we define effectual connectivity as the fraction of synaptically linked neuron pairs within a cell assembly representing a memory. We show by theory and numerical simulation the close links between effectual connectivity and both information storage capacity of neural networks and effective connectivity as commonly employed in functional brain imaging and connectome analysis. Then, by applying our model to a recently proposed memory model, we can give improved estimates on the number of cell assemblies that can be stored in a cortical macrocolumn assuming realistic connectivity. Finally, we derive a simplified model of structural plasticity to enable large scale simulation of memory phenomena, and apply our model to link ongoing adult structural plasticity to recent behavioral data on the spacing effect of learning. [ABSTRACT FROM AUTHOR]

Historically, models of categorization have focused on how learners track frequencies and co-occurrence information to abstract relevant category features for generalization. The current study takes a different approach by examining how the temporal dynamics of categorization affect abstraction and generalization. In the learning phase of the experiment, all relevant category features were presented an equal number of times across category exemplars. However, the relevant features were presented on one of two learning schedules: massed or interleaved. At a series of immediate and delayed tests, learners were asked to generalize to novel exemplars that contained massed features, interleaved features, or all novel features. The results of this experiment revealed that, at an immediate test, learners more readily generalized based upon features presented on a massed schedule. Conversely, at a delayed test, learners more readily generalized based upon features presented on an interleaved schedule, until information was no longer readily retrievable from memory. These findings suggest that forgetting and retrieval processes engendered by the temporal dynamics of learning are used as a basis of abstraction, implicating forgetting as a central mechanism of generalization.

Inductive learning takes place when people learn a new concept or category by observing a variety of exemplars. Kornell and Bjork (2008) asked participants to learn new painting styles either by presenting different paintings of the same artist consecutively (massed presentation) or by mixing paintings of different artists (spaced presentation). In their second experiment, Kornell and Bjork showed with a final style recognition test, that spacing resulted in better inductive learning than massing. Also, by using this style recognition test, they ruled out the possibility that spacing merely resulted in a better memory for the labels of the newly learned painting styles. The findings from Kornell and Bjork’s second experiment are important because they show that the benefit of spaced learning generalizes to complex learning tasks and outcomes, and that it is not confined to rote memory learning. However, the findings from Kornell and Bjork’s second experiment have never been replicated. In the present study we performed an exact and high-powered replication of Kornell and Bjork’s second experiment with a Web-based sample. Such a replication contributes to establish the reliability of the original finding and hence to more conclusive evidence of the spacing effect in inductive learning. The findings from the present replication attempt revealed a medium-sized advantage of spacing over massing in inductive learning, which was comparable to the original effect in the experiment by Kornell and Bjork. Also, the 95% confidence intervals of the effect sizes from both experiments overlapped considerably. Hence, the findings from the present replication experiment and the original experiment clearly reinforce each other.

We assessed the effects of removing some constraints that characterise traditional experiments on the effects of spaced, rather than massed, study opportunities. In five experiments-using lists of to-be-remembered words-we examined the effects of how total study time was distributed across multiple repetitions of a given to-be-remembered word. Overall, within a given list, recall profited from study time being distributed (e.g., four 1-s presentations or two 2-s presentations vs one 4-s presentation). Among the implications of these findings is that if students choose to engage in massed studying (by virtue of constraints on their study time or a failure to appreciate the benefits of spaced study sessions), then studying the information twice but for half the time may produce memory benefits in a single study session.

This paper presents a numerical study using three-dimensional (3D) finite-element (FE) analyses for slopes that contain a weak thin layer and are reinforced with piles. The presence of a thin weak layer usually has a negative effect on slope stability. In the FE analysis, a strength reduction technique is employed using FE software. In the numerical model, an elastic-perfectly plastic with Mohr-Coulomb failure criterion is used for the soils. The pile is assumed to be an elastic member, without considering failure. Some of the effective factors, such as the optimal pile location and pile length, were verified beforehand using two-dimensional (2D) FE analysis. The spacing effect of the pile, S=D54:0 (S is oncenter spacing;D is diameter), is found to be comparable for the 3D model in relation to the 2D model. The appropriate length of the pile used in the 3D analysis is based on the length of piles typically used in engineering practice. It is concluded that proper stabilization can be provided if approximately half of the pile length extends below the weak layer and piles are installed in the middle portion of the slope. The analysis methods are based on a coupled analysis method; that is, both slope stability and pile response are considered simultaneously. Also, the 3DFEMis able to overcome the limitations of the 2D FE model that lacks proper consideration of the boundary effect, the soil movement between the piles, and the spacing between the piles. The effectiveness of the pile-stabilized slope depends on the strength of the soil contained in the interbedded layer. Slope stability analysis for a slope with piles was also performed, whereby three typical failure mechanisms were observed, from translational to rotational failure for the different Cu2=Cu1 ratios (Cu1 is the undrained shear strength of the slope soil, and Cu2 is the undrained shear strength of the soil in a thin layer). The presence of the stabilizing piles in such a slope can change the failure mechanisms and the depth of the slip surface. The restricted conditions applied to the pile head are also found to have similar effects in changing the failure mechanisms in a slope. Fixed-head piles are found to provide substantially more improvement to slope stability than free-head piles. However, fixed-head piles are not always recommended, depending on the Cu2=Cu1 ratio and the required factor of safety after being stabilized with piles. This paper also provides a realistic soil-pile interaction model that is subjected to lateral loading on an inclined slope. [ABSTRACT FROM AUTHOR]

Education ideally should induce learning that lasts for years and more. A wealth of research indicates that, to achieve long-lasting retention, information must be practiced and/or tested repeatedly, with repeated practice well distributed over time. In this paper we discuss the behavioral, neuroimaging and neurophysiological findings related to the effect of distributed practice and testing as well as the resulting theoretical accounts. Distributed practice and testing appear to be powerful learning tools. We consider implications of these learning principles for educational practice. [ABSTRACT FROM AUTHOR]