Gradual training reduces practice difficulty while preserving motor learning of a novel locomotor task

Motor learning strategies that increase practice difficulty and the size of movement errors are thought to facilitate motor learning. In contrast to this, gradual training minimizes movement errors and reduces practice difficulty by incrementally introducing task requirements, yet remains as effective as sudden training and its large movement errors for learning novel reaching tasks. While attractive as a locomotor rehabilitation strategy, it remains unknown whether the efficacy of gradual training extends to learning locomotor tasks and their unique requirements. The influence of gradual vs. sudden training on learning a locomotor task, asymmetric split belt treadmill walking, was examined by assessing whole body sagittal plane kinematics during 24 hour retention and transfer performance following either gradual or sudden training. Despite less difficult and less specific practice for the gradual cohort on day 1, gradual training resulted in equivalent motor learning of the novel locomotor task as sudden training when assessed by retention and transfer a day later. This suggests that large movement errors and increased practice difficulty may not be necessary for learning novel locomotor tasks. Further, gradual training may present a viable locomotor rehabilitation strategy avoiding large movement errors that could limit or impair improvements in locomotor performance.     

Obstacle avoidance in novel visual environments improved by variable practice training

Motor performance on simple tasks improves after training in variable practice. We asked if locomotor skill during an obstacle-avoidance task in a novel sensorimotor environment improved through training in variable practice on other complex tasks. 40 normal adults practiced gross motor skills while wearing either sham lenses, one of several visual distortion lens (constant practice), or three different visual distortion lenses (variable practice). Posttests on obstacle avoidance with novel lenses showed significantly better scores with variable practice and one of the constant groups vs sham lenses. Constant and variable practice groups did not differ. Thus, performance in a novel environment improves after training on similar type novelty, even when practice and test conditions differ. Constant practice was effective only if the subjects used the lens efficacious in training. Variable practice increases the likelihood of efficacious training when adaptive performance is required in a novel environment.     

二年级小学生“记”“忆”策略的微观发生研究

采用微观发生法,以33名小学二年级学生为被试,以记忆书面语词的分类材料为任务,对儿童记忆过程中"记"、"忆"策略的不同发展规律进行了5个期间的测查.结果发现:(1)分类记忆策略的发展既有突变过程也有渐变过程:分类记策略有生成缺陷,表现为训练后的突然变化;分类忆策略则是一个可以自发形成的渐变过程,如果加以适当的训练也会发生突然的增长.(2)在材料熟悉度较低的情况下,会使少量儿童产生分类记、忆策略使用缺陷现象.     

Walking on an Oscillating Treadmill: Strategies of Stride-Time Adaptation

Gains in mobility, balance, and gait quality have been observed in clinical populations after treadmill training. In our laboratory, we introduce healthy adults to treadmill training programs in an effort to boost their adaptive generalization skills. We hypothesized that some individuals are more naturally predisposed to gait adaptation than others. Stride-time data from 20 healthy adults were collected while they walked on a laterally oscillating treadmill for the first time. We predicted that the more plastic adapters would rapidly synchronize their stride frequencies to the treadmill's oscillation frequency. A treadmill mounted on a 6-degrees-of-freedom motion base platform was programmed to move laterally in a continuous, sinusoidal pattern for 20 min while participants walked at 1.1 m/s. Twenty-five percent of our participants showed a prolonged uninstructed entrained response. Those who did not entrain were still able to adapt to the novel locomotor challenge by applying various alternative strategies. Although entrainment was not required for adaptation, we report compelling evidence that the frequency of the support-surface motion influenced the adapted strategies of 80% of our participants.     

Memory training interventions require a tailor-made approach: Commentary on McDaniel and Bugg

Memory training for older adults often produces gains that are limited to the particular memory tasks encountered during training. We suggest that memory training programs may be misguided by an implicit "generalist" assumption-memory training on a couple of memory tasks will have a positive benefit on memory ability in general. One approach to increase memory-training benefits is to target training for the everyday memory tasks for which older adults struggle. Examples include training retrieval strategies, prospective memory strategies, and strategies for learning and remembering names. Another approach is to design training to foster transfer. Possible elements to improve transfer are increasing the variation that is experienced during the course of training at the level of stimuli and tasks, incorporating "homework" that guides the older adult to become attuned to situations in which the strategies can be applied, and providing older adults with a better understanding of how memory works. Finally, incorporating aerobic exercise into memory training programs may potentiate the acquisition and maintenance of the trained cognitive strategies.     

Enhancing the Cognitive Vitality of Older Adults

Aging is associated with decline in a multitude of cognitive processes and brain functions. However, a growing body of literature suggests that age-related decline in cognition can sometimes be reduced through experience, cognitive training, and other interventions such as fitness training. Research on cognitive training and expertise has suggested that age-related cognitive sparing is often quite narrow, being observed only on tasks and skills similar to those on which individuals have been trained. Furthermore, training and expertise benefits are often realized only after extensive practice with specific training strategies. Like cognitive training, fitness training has narrow effects on cognitive processes, but in the case of fitness training, the most substantial effects are observed for executive-control processes.     

Parkinson's disease differentially affects adaptation to gradual as compared to sudden visuomotor distortions

Patients with Parkinson’s disease (PD) have difficulties in movement adaptation to optimize performance in novel environmental contexts such as altered screen cursor-hand relationships. Prior studies have shown that the time course of the distortion differentially affects visuomotor adaptation to screen cursor rotations, suggesting separate mechanisms for gradual and sudden adaptation. Moreover, studies in human and non-human primates suggest that adaptation to sudden kinematic distortions may engage the basal ganglia, whereas adaptation to gradual kinematic distortions involves cerebellar structures. In the present studies, participants were patients with PD, who performed center-out pointing movements, using either a digitizer tablet and pen or a computer trackball, under normal or rotated screen cursor feedback conditions. The initial study tested patients with PD using a cross-over experimental design for adaptation to gradual as compared with sudden rotated hand-screen cursor relationships and revealed significant after-effects for the gradual adaptation task only. Consistent with these results, findings from a follow-up experiment using a trackball that required only small finger movements showed that patients with PD adapt better to gradual as against sudden perturbations, when compared to age-matched healthy controls. We conclude that Parkinson’s disease affects adaptation to sudden visuomotor distortions but spares adaptation to gradual distortions.     

Step by step: A microgenetic study of the development of strategy choice in infancy

To examine patterns of strategy choice and discovery during problem‐solving of a novel locomotor task, 13.5‐ and 18‐month‐old infants were placed at the top of a staircase and encouraged to descend. Spontaneous stair descent strategy choices were documented step by step and trial by trial to provide a microgenetic account of problem‐solving in action. Younger infants tended to begin each trial walking, were more likely to choose walking with each successive step, and were more likely to lose their balance and have to be rescued by an experimenter. Conversely, older infants tended to begin each trial scooting, were more likely to choose scooting with each successive step, and were more likely to use a handrail to augment balance on stairs. Documenting problem‐solving microgenetically across age groups revealed striking similarities between younger infants' strategy development and older children's behaviour on more traditionally cognitive tasks, including using alternative strategies, mapping prior experiences with strategies to a novel task, and strengthening new strategies. As cognitive resources are taxed during a challenging task, resources available for weighing alternatives or inhibiting a well‐used strategy are reduced. With increased motor experience, infants can more easily consider alternative strategies and maintain those solutions over the course of the trial.     

Crosswords to Computers: A Critical Review of Popular Approaches to Cognitive Enhancement

Cognitive enhancement strategies have gained recent popularity and have the potential to benefit clinical and non-clinical populations. As technology advances and the number of cognitively healthy adults seeking methods of improving or preserving cognitive functioning grows, the role of electronic (e.g., computer and video game based) cognitive training becomes more relevant and warrants greater scientific scrutiny. This paper serves as a critical review of empirical evaluations of publically available electronic cognitive training programs. Many studies have found that electronic training approaches result in significant improvements in trained cognitive tasks. Fewer studies have demonstrated improvements in untrained tasks within the trained cognitive domain, non-trained cognitive domains, or on measures of everyday function. Successful cognitive training programs will elicit effects that generalize to untrained, practical tasks for extended periods of time. Unfortunately, many studies of electronic cognitive training programs are hindered by methodological limitations such as lack of an adequate control group, long-term follow-up and ecologically valid outcome measures. Despite these limitations, evidence suggests that computerized cognitive training has the potential to positively impact one’s sense of social connectivity and self-efficacy.     

Discovery Learning and Transfer of Problem-Solving Skills

A framework for understanding the effects of discovery learning on the transfer of problem-solving skill is presented. A distinction is drawn between applying a learned strategy on a transfer problem versus having to generate a novel strategy to solve a transfer problem. The main premise of the framework is that requiring discovery of a strategy while in training encourages the activation or refinement of procedures that are useful for generating a novel strategy. In general, then, the primary benefit of discovery is that it should facilitate transfer to tasks requiring a novel strategy. Learning by discovery, however, may provide little benefit for tasks that can be completed only by applying the learned strategy. Two experiments provided support and further refinement of this hypothesis. Experiment 1 used a transfer problem that could be solved with the general strategy learned in training but required new move sequences to instantiate the strategy. The results indicated that, when transfer required new move sequences to implement a general strategy learned previously, discovery did not enhance transfer of that strategy. In experiment 2, some transfer problems required using a strategy other than that learned in training. As predicted, in this transfer situation, having to discover a strategy while in training produced better transfer than being provided with a strategy in training. Thus, discovering a strategy provided benefits when a new strategy had to be generated to solve a transfer problem but not when the learned strategy could be applied, albeit with new moves, to the transfer problem. Educational implications are discussed.     

基于认知加工过程的数学训练方案述评

数学训练方案（Modules for Math）是加拿大心理学家J.P.Das提出的促进数学学习的训练方案。该方案的理论基础是基于Luria神经三级网络的PASS（计划-注意-同时性加工-继时性加工）模型以及Vygotsky主张以言语内化方式进行自我学习的教育原则。数学训练方案包括模式转换;学习数轴;数一数;模仿、画路径和估算;数字记忆广度等五个训练模块,通过大约五十多个活动任务实现一般认知加工的促进,同时迁移到数学学习的课程中。数学训练方案今后将结合行为实验与认知神经影像学数据,证实训练的效果及变化。     

Prospective memory training in older adults and its relevance for successful aging

In research on cognitive plasticity, two training approaches have been established: (1) training of strategies to improve performance in a given task (e.g., encoding strategies to improve episodic memory performance) and (2) training of basic cognitive processes (e.g., working memory, inhibition) that underlie a range of more complex cognitive tasks (e.g., planning) to improve both the training target and the complex transfer tasks. Strategy training aims to compensate or circumvent limitations in underlying processes, while process training attempts to augment or to restore these processes. Although research on both approaches has produced some promising findings, results are still heterogeneous and the impact of most training regimes for everyday life is unknown. We, therefore, discuss recent proposals of training regimes aiming to improve prospective memory (i.e., forming and realizing delayed intentions) as this type of complex cognition is highly relevant for independent living. Furthermore, prospective memory is associated with working memory and executive functions and age-related decline is widely reported. We review initial evidence suggesting that both training regimes (i.e., strategy and/or process training) can successfully be applied to improve prospective memory. Conceptual and methodological implications of the findings for research on age-related prospective memory and for training research in general are discussed.     

任务结构相似性对工作记忆训练迁移效应的影响

研究发现,个体的工作记忆能力通过训练可以提高。但是,目前对于工作记忆训练的迁移效应,尚未有统一的结论。本文通过梳理相关研究,发现训练任务与评估迁移效应任务之间的结构相似性会对迁移效应产生影响。结构相似性即训练任务和未训练任务之间共享加工和加工程序,而这个共享加工和加工程序能通过发展相似的策略实现工作记忆训练的迁移。今后研究应该更加注意以往研究设计中的不足,针对不同群体的工作记忆训练效果的机制分别进行研究。     

Development of Numberline and Measurement Concepts

In a two-part study, children in Grades 1 through 3 were given a set of numberline estimation problems and a set of similar numberline estimation problems that were to be solved using specially designed rulers. The estimation tasks showed a complex pattern of change in accuracy and strategies over the three grade levels. This pattern indicated that children progressively altered their estimation strategies from strictly sequential ones to ones that incorporate elements of proportional reasoning. This shift was gradual and implemented school-learned numerical relationships in the solution of these novel tasks. There was no indication that, in the Piagetian sense, stage changes contributed to strategy development. However, the use of rulers with different spacings between the numbers indicated that children's acquisition of a principled concept of equal intervals required both the learned convention of equal intervals and the achievement of conservation of length.     

Working memory training improvements and gains in non-trained cognitive tasks in young and older adults

Previous studies on working memory training have indicated that transfer to non-trained tasks of other cognitive domains may be possible. The aim of this study is to compare working memory training and transfer effects between younger and older adults (n = 60). A novel approach to adaptive n-back training (12 sessions) was implemented by varying the working memory load and the presentation speed. All participants completed a neuropsychological battery of tests before and after the training. On average, younger training participants achieved difficulty level 12 after training, while older training participants only reached difficulty level 5. In younger participants, transfer to Verbal Fluency and Digit Symbol Substitution test was found. In older participants, we observed a transfer to Digit Span Forward, CERAD Delayed Recall, and Digit Symbol Substitution test. Results suggest that working memory training may be a beneficial intervention for maintaining and improving cognitive functioning in old age.     

Does working memory training promote the use of strategies on untrained working memory tasks?

Adaptive computerized training has been associated with significant enhancements in untrained working memory tasks, but the nature of the cognitive changes that underpin these improvements are not yet fully understood. Here, we investigate the possibility that training stimulates the use of memory-related strategies. In a randomized controlled trial, participants completed four tests of working memory before receiving adaptive working memory training, nonadaptive working memory training with low memory loads, or no training. Open-ended interviews about strategy use were conducted after the administration of untrained working memory tasks at two time points. Those in the adaptive and nonadaptive groups completed the assessments before (T1) and after (T2) 10 training sessions. The no-training group completed the same set of tasks at T1 and T2, without any training between assessment points. Adaptive training was associated with selective improvements in untrained tests of working memory, accompanied by a significant increase in the use of a grouping strategy for visuospatial short-term memory and verbal working memory tasks. These results indicate that training-related improvements in working memory may be mediated by implicit and spontaneous changes in the use of strategies to subsegment sequences of information into groups for recall when the tasks used at test overlap with those used during training.     

Effect of working memory training on working memory,arithmetic and following instructions

Mathematical ability is dependent on specific mathematical training but also associated with a range of cognitive factors, including working memory (WM) capacity. Previous studies have shown that WM training leads to improvement in non-trained WM tasks, but the results regarding transfer to mathematics are inconclusive. In the present study, 176 children with WM deficits, aged 7–15 years performed 5 weeks of WM training. During the training period, they were assessed five times with a test of complex WM (the Odd One Out), a test of remembering and following instructions and a test of arithmetic. The improvements were compared to the performance of a control group of 304 typically developing children aged 7–15 years who performed the same transfer tasks at the same time intervals, but without training. The training group improved significantly more than the control group on all three transfer tests (all p < 0.0001), after correction for baseline performance, age and sex. The effect size for mathematics was small and the effect sizes for the WM tasks were moderate to large. The transfer increased linearly with the amount of training time and correlated with the amount of improvement on the trained tasks. These results confirm previous findings of training-induced improvements in non-trained WM tasks including the ability to follow instructions, but extend previous findings by showing improvements also for arithmetic. This is encouraging regarding the potential role of cognitive training for education, but it is desirable to find paradigms that would enhance the effect of the training on mathematics. One of the future challenges for studying training effects is combining large sample sizes with high quality and compliance, to detect relevant but smaller effects of cognitive training.     

Longitudinal attentional engagement rescues mice from age-related cognitive declines and cognitive inflexibility

Learning, attentional, and perseverative deficits are characteristic of cognitive aging. In this study, genetically diverse CD-1 mice underwent longitudinal training in a task asserted to tax working memory capacity and its dependence on selective attention. Beginning at 3 mo of age, animals were trained for 12 d to perform in a dual radial-arm maze task that required the mice to remember and operate on two sets of overlapping guidance (spatial) cues. As previously reported, this training resulted in an immediate (at 4 mo of age) improvement in the animals' aggregate performance across a battery of five learning tasks. Subsequently, these animals received an additional 3 d of working memory training at 3-wk intervals for 15 mo (totaling 66 training sessions), and at 18 mo of age were assessed on a selective attention task, a second set of learning tasks, and variations of those tasks that required the animals to modify the previously learned response. Both attentional and learning abilities (on passive avoidance, active avoidance, and reinforced alternation tasks) were impaired in aged animals that had not received working memory training. Likewise, these aged animals exhibited consistent deficits when required to modify a previously instantiated learned response (in reinforced alternation, active avoidance, and spatial water maze). In contrast, these attentional, learning, and perseverative deficits were attenuated in aged animals that had undergone lifelong working memory exercise. These results suggest that general impairments of learning, attention, and cognitive flexibility may be mitigated by a cognitive exercise regimen that requires chronic attentional engagement.     

From specific examples to general knowledge in language learning

The extraction of general knowledge from individual episodes is critical if we are to learn new knowledge or abilities. Here we uncover some of the key cognitive mechanisms that characterise this process in the domain of language learning. In five experiments adult participants learned new morphological units embedded in fictitious words created by attaching new affixes (e.g., -afe) to familiar word stems (e.g., “sleepafe is a participant in a study about the effects of sleep”). Participants’ ability to generalise semantic knowledge about the affixes was tested using tasks requiring the comprehension and production of novel words containing a trained affix (e.g., sailafe). We manipulated the delay between training and test (Experiment 1), the number of unique exemplars provided for each affix during training (Experiment 2), and the consistency of the form-to-meaning mapping of the affixes (Experiments 3–5). In a task where speeded online language processing is required (semantic priming), generalisation was achieved only after a memory consolidation opportunity following training, and only if the training included a sufficient number of unique exemplars. Semantic inconsistency disrupted speeded generalisation unless consolidation was allowed to operate on one of the two affix-meanings before introducing inconsistencies. In contrast, in tasks that required slow, deliberate reasoning, generalisation could be achieved largely irrespective of the above constraints. These findings point to two different mechanisms of generalisation that have different cognitive demands and rely on different types of memory representations.     

One executive function never comes alone: monitoring and its relation to working memory,reasoning, and different executive functions

Monitoring is involved in many daily tasks and is described in several theoretical approaches of executive functioning. This study investigated the relative relationship of cognitive processes that are theoretically relevant to monitoring, such as concept formation, reasoning, working memory, and general cognitive control functions. Data from 699 participants who performed the Balanced Switching Task, aiming at capturing monitoring, were used. Subsamples also performed standard tasks assessing the processes assumed to be related to monitoring. Structural equation modeling revealed that general cognitive control processes are particularly relevant. They mediate the relationship between working memory, reasoning, and monitoring. Updating and maintaining information, as well as concluding from information which strategies can guide behavior toward predefined goals, is required for the ability to exert general cognitive control, which again may be relevant for implementing strategies in a goal-directed way. Together, these processes seem to be necessary to adequately monitor behavior in complex tasks.