Implicit and explicit processes in a second-language learning task

Abstract

Two experiments examined the learning of a set of Greek pronunciation rules through explicit and implicit modes of rule presentation. Experiment 1 compared the effectiveness of implicit and explicit modes of presentation in two modalities, visual and auditory. Subjects in the explicit or rule group were presented with the rule set, and those in the implicit or natural group were shown a set of Greek words, composed of letters from the rule set, linked to their pronunciations. Subjects learned the Greek words to criterion and were then given a series of tests which aimed to tap different types of knowledge. The results showed an advantage of explicit study of the rules. In addition, an interaction was found between mode of presentation and modality. Explicit instruction was more effective in the visual than in the auditory modality, whereas there was no modality effect for implicit instruction. Experiment 2 examined a possible reason for the advantage of the rule groups by comparing different combinations of explicit and implicit presentation in the study and learning phases. The results suggested that explicit presentation of the rules is only beneficial when it is followed by practice at applying them.     

Perceptual training methods compared: the relative efficacy of different approaches to enhancing sport-specific anticipation

The comparative efficacy of different perceptual training approaches for the improvement of anticipation was examined using a goalkeeping task from European handball that required the rapid prediction of shot direction. Novice participants (N = 60) were assigned equally to four different training groups and two different control groups (a placebo group and a group who undertook no training). The training groups received either (i) explicit rules to guide anticipation; (ii) direction as to the location of the key anticipatory cues provided either just verbally (verbal cueing) or supplemented with color highlighting (color cueing); or (iii) undertook a matching judgment task to encourage implicit learning. Performance of the groups was compared on an anticipation test administered before training, after the training intervention, under a condition involving evaluative stress, and after a 5-month retention period. The explicit learning, verbal cueing, and implicit learning conditions provided the greatest sustained improvements in performance whereas the group given color cueing performed no better than the control groups. Only the implicit learning group showed performance superior to the control groups under the stress situation. The verbal cueing, color cueing, and implicit learning groups formulated the lowest number of explicit rules related to the critical shoulder cue although the reported use of general cues and rules based on all cues did not differ between any of the groups. Anticipation can be improved through a variety of different perceptual training approaches with the relative efficacy of the different approaches being contingent upon both the time scale and conditions under which learning is assessed.     

Learning from implicit learning literature: Comment on Shea, Wulf, Whitacre, and Park (2001)

In their analysis of complex motor skill learning, Shea, Wulf, Whitacre, and Park (2001) have overlooked one of the most robust conclusions of the experimental studies on implicit learning conducted during the last decade--namely that participants usually learn things that are different from those that the experimenter expected them to learn. Weshow that the available literature on implicit learning strongly suggests that the improved performance in Shea et al.'s Experiments 1 and 2 (and similar earlier experiments, e.g., Wulf & Schmidt, 1997) was due to the exploitation of regularities in the target pattern different from those on which the postexperimental interview focused. This rules out the conclusions drawn from the failure of this interview to reveal any explicit knowledge about the task structure on the part of the participants. Similarly, because the information about the task structure provided to an instructed group of participants in Shea et al.'s Experiment 2 did not concern the regularities presumably exploited by the standard, so-called implicit, group, Shea et al.'s claim that explicit knowledge may be less effective than implicit knowledge is misleading.     

Implicit versus explicit learning processes in a probabilistic, continuous fine-motor catching task

We compared the influences of explicit instruction and uninstructed implicit learning of correlations among visual events, in a fine-motor task. The task required visual tracking of a small "ball" of light and "catching" it by means of joystick manipulation. A general pattern of improvement with practice for instructed and "noninstructed" conditions was found. Additionally, both instructed and noninstructed conditions evidenced use of the predictive relationships among stimulus events. The improvement in overall performance caused by explicit verbal instructions was less than the improvement seen with the implicit learning condition. Further, instructed and noninstructed conditions showed different patterns of joystick activity. These findings suggest a qualitatively different approach to visual information processing and task performance for the instructional conditions     

The implicit benefit of learning without errors

Two studies examined whether the number of errors made in learning a motor skill, golf putting, differentially influences the adoption of a selective (explicit) or unselective (implicit) learning mode. Errorful learners were expected to adopt an explicit, hypothesis-testing strategy to correct errors during learning, thereby accruing a pool of verbalizable rules and exhibiting performance breakdown under dual-task conditions, characteristic of a selective mode of learning. Reducing errors during learning was predicted to minimize the involvement of explicit hypothesis testing leading to the adoption of an unselective mode of learning, distinguished by few verbalizable rules and robust performance under secondary task loading. Both studies supported these predictions. The golf putting performance of errorless learners in both studies was unaffected by the imposition of a secondary task load, whereas the performance of errorful learners deteriorated. Reducing errors during learning limited the number of error-correcting hypotheses tested by the learner, thereby reducing the contribution of explicit processing to skill acquisition. It was concluded that the reduction of errors during learning encourages the use of implicit, unselective learning processes, which confer insusceptibility to performance breakdown under distraction.     

The effect of implicit and explicit practice in the development of decision making in volleyball serving

This experiment investigated the effect of explicit, implicit, and sequential learning (implicit-explicit) on the acquisition and retention of decision-making skill in volleyball. The participants were 60 female novices, ages 10 to 12 years. The experimental groups followed three different methods of training: (a) explicit practice for the development of declarative knowledge, (b) implicit practice for the development of the procedural knowledge, (c) sequential practice (implicit first and then explicit), and (d) control group that participated only in the measurements. A pre-test, a post-test, and a retention test measured the response time and accuracy of the decision-making skill. Analysis indicated that all experimental groups improved over time while the control group did not. The sequential group was faster and more accurate than the implicit group, and the latter was faster and more accurate than the explicit one. The sequential group outperformed implicit and explicit groups on both speed and accuracy of decision. It seems that both explicit and implicit processes, when they take place in sequence, interact positively, and this method improves speed and accuracy of decision making rather than when each mode of learning (implicit or explicit) occurs separately. If the role of working memory is reduced at the early stages of learning, the accumulation of declarative knowledge (explicit learning) may benefit from accumulation of procedural knowledge and enhance decision-making skill.     

The time course of implicit and explicit concept learning

The present experiment investigated the development of implicit and explicit knowledge during concept learning. According to Cleeremans and Jiménez (2002), the content of a representation can be conscious only when the representation is of a sufficiently good quality; on this theory, increasing explicit and decreasing implicit knowledge might be expected with training. The view that implicit knowledge arises from compilation of explicit knowledge makes the opposite prediction. The present research tested these possibilities using subjective measures based on confidence ratings. One group of participants was presented with blocks of category exemplars that activated prior knowledge, whereas another group was presented with blocks of categories that did not elicit any useful prior knowledge. The results showed that, irrespective of the knowledge group participants were allocated to, explicit knowledge increased over the course of learning, whereas implicit knowledge either stayed the same or decreased, consistent with Cleeremans and Jiménez's prediction.     

试析内隐学习的长时功效

内隐学习的长时功效是指 ,其发生是自动的 ,但是需要一定时间的练习积累 ;内隐学习的效果是抗干扰的 ,但是其进程仍然是动态发展的。长时功效的提出 ,促使人们在理论上反思内隐学习的特性、内隐学习和外显学习的关系、乃至整体的知识表征问题 ;在实践上则为内隐学习的合理诱发和充分利用提供了借鉴。     

Explicit Learning of a Dynamic System with a Non-salient Pattern

We examine the hypothesis that a specific goal leads to implicit learning, whereas a nonspecific goal leads to explicit learning, even though the pattern to be learnt is non-salient. Subjects learned a dynamic control task (Berry & Broadbent, 1984). One group of subjects had a specific control goal, the second group had a non-specific pattern-search goal, and the third group had both goals. On measures of learning (control performance, prediction, and general questions), the non-specific group learnt explicitly, outperforming the other two groups on all learning measures. The specific group performed next best on control performance and prediction questions but performed very poorly on general questions. The dual-goal group performed poorly on all measures. Non-specific subjects predicted well on both familiar and unfamiliar situations. Specific-goal subjects predicted well on familiar situations, regardless of whether their previous response had been correct or incorrect. Dual-goal subjects predicted well only on familiar correct situations. We conclude that the non-specific group learned through explicit hypothesis testing, the specific group learned through a mixture of explicit problem solving and implicit instance learning, and the dual-goal group learned instances. Results are discussed in terms of dual-space models of problem solving and hypothesis testing and in terms of implicit instance learning. We consider how the choice of learning goal affects the cognitive processes used during learning and suggest that having subjects learn the same information implicitly or explicitly is potentially useful for drawing clearer distinctions between implicit and explicit modes of learning.     

分布式群体在动态系统控制决策中的内隐学习

采用计算机网络模拟技术,考察分布式群体在动态系统控制决策过程中对系统规则的内隐学习效应及其迁移。结果表明,在决策者的显性规则知识量极少且没有增加的情况下,决策绩效随决策进程适应性提高。决策者所能报告的规则知识量与决策绩效的相关也不显著。同时,当决策任务目标转换时,决策的高绩效得以维持。这表明群体决策者能对动态系统规则进行内隐学习,且能正迁移到类似的决策情景中。研究进一步指出,群体决策行为的动态适应与内隐过程有关。     

Explicit Awareness does not Modulate Retrograde Interference Effects in Sequence Learning

Motor sequences are learned explicitly or implicitly based on conscious awareness of the sequence. Interference happens when two sequences are learned successively. Here, we aimed to determine whether implicit and explicit sequence learning are affected differently by retrograde interference. Young healthy volunteers participated in either a control or interference group and either an explicit or implicit learning condition. We used a modified serial reaction time task to induce sequence learning and control awareness. Results showed that the overall amount of sequence learning was greater in the explicit condition compared to implicit. However, sequence learning was equally susceptible to retrograde interference under either condition. We conclude that although susceptible to interference, explicit awareness improves overall sequence learning compared to implicit conditions.     

How does prior knowledge affect implicit and explicit concept learning?

Two experiments investigated the effect of prior knowledge on implicit and explicit learning. Implicit as opposed to explicit learning is sometimes characterized as unselective or purely statistical. During training, one group of participants was presented with category exemplars whose features could be tied together by integrative knowledge, whereas another group saw category exemplars with unrelated feature combinations. Half of the participants in each group learned these categories under a secondary-task condition (meant to discourage explicit learning), and the remaining half performed the categorization task under a single-task condition (meant to favour explicit learning). In a test phase, participants classified only the individual features of the training exemplars. Secondary- as opposed to single-task conditions impaired explicit but not implicit knowledge (as determined by subjective measures). Importantly, prior knowledge resulted in increased amounts of both implicit and explicit knowledge.     

The emergence of explicit knowledge during the early phase of learning in sequential reaction time tasks

Five experiments investigated the formation of explicit knowledge of a repeating sequence in a sequential reaction time task. Reliable explicit knowledge was obtained even though various conditions prevented the selective improvement of RTs (Exps. 1–4). This knowledge emerged early during training. Participants were able to recognize segments of the sequence (Exps. 3 and 4) or correctly assess the probabilities of transition of the target between successive locations (Exp. 5) after only two blocks of training trials. These findings rule out an interpretation of sequence learning that posits that explicit knowledge emerges from implicit knowledge during the course of training. Although these findings are compatible with a framework centered around the notion of dissociation between implicit and explicit knowledge, they are also consonant with a questioning of the usefulness of the concept of implicit knowledge.     

Psychometric intelligence dissociates implicit and explicit learning

The hypothesis that performance on implicit learning tasks is unrelated to psychometric intelligence was examined in a sample of 605 German pupils. Performance in artificial grammar learning, process control, and serial learning did not correlate with various measures of intelligence when participants were given standard implicit instructions. Under an explicit rule discovery instruction, however, a significant relationship between performance on the learning tasks and intelligence appeared. This finding provides support for Reber's hypothesis that implicit learning, in contrast to explicit learning, is independent of intelligence, and confirms thereby the distinction between the 2 modes of learning. However, because there were virtually no correlations among the 3 learning tasks, the assumption of a unitary ability of implicit learning was not supported.     

Passing thoughts on the evolutionary stability of implicit motor behaviour: performance retention under physiological fatigue

Heuristics of evolutionary biology (e.g., survival of the fittest) dictate that phylogenetically older processes are inherently more stable and resilient to disruption than younger processes. On the grounds that non-declarative behaviour emerged long before declarative behaviour, Reber (1992) argues that implicit (non-declarative) learning is supported by neural processes that are evolutionarily older than those supporting explicit learning. Reber suggested that implicit learning thus leads to performance that is more robust than explicit learning. Applying this evolutionary framework to motor performance, we examined whether implicit motor learning, relative to explicit motor learning, conferred motor output that was resilient to physiological fatigue and durable over time. In Part One of the study a fatigued state was induced by a double Wingate Anaerobic test protocol. Fatigue had no affect on performance of participants in the implicit condition; whereas, performance of participants in the explicit condition deteriorated significantly. In Part Two of the study a convenience sample of participants was recalled following a one-year hiatus. In both the implicit and the explicit condition retention of performance was seen and, contrary to the findings in Part One, so was resilience to fatigue. The resilient performance in the explicit condition after one year may have resulted from forgetting (the decay of declarative knowledge) or from consolidation of declarative knowledge as implicit memories. In either case, implicit processes were left to more effectively support motor performance.     

The role of working memory capacity in implicit and explicit sequence learning of children: Differentiating movement speed and accuracy

This study investigated the role of working memory capacity on implicit and explicit motor sequence learning in young children. To this end, a task was utilized that required a gross motor response (flexing the elbow) and that could differentiate between movement speed (i.e., reaction time and movement time) and movement accuracy. Children aged 7–9 years practiced a serial reaction time task that involved the production of a fixed sequence of elbow flexions of prescribed magnitude across two consecutive days. Children in the explicit group were informed about the presence of the sequence and were shown this sequence, while children in the implicit group were not made aware of the sequence. Additionally, children's verbal and visuospatial working memory capacity was assessed. Results of day 1 regarding movement speed revealed no evidence of sequence learning for either group, but movement accuracy results suggested that sequence learning occurred for the implicit group. For both groups, only improvements in movement accuracy were consolidated on day 2, indicating both general and sequence specific learning. Working memory capacity did not correlate with learning in either of the groups. Children in the explicit group accumulated more sequence knowledge compared to children in the implicit group, but this knowledge did not translate to more or better sequence learning. The minimal differences found between the implicit and explicit condition and the absence of a role for working memory capacity add to the increasing evidence that the observed differences between implicit and explicit sequence learning in adults may be less distinct in children.     

Learning New Letter-like Writing Patterns Explicitly and Implicitly in Children and Adults

A handwriting task was used to test the assumption that explicit learning is dependent on age and working memory, while implicit learning is not. The effect of age was examined by testing both, typically developing children (5–12 years old, n = 81) and adults (n = 27) in a counterbalanced within-subjects design. Participants were asked to repeatedly write letter-like patterns on a digitizer with a non-inking pen. Reproduction of the pattern was better after explicit learning compared to implicit learning. Age had positive effects on both explicit and implicit learning; working memory did not affect learning in either conditions. These results show that it may be more effective to learn writing new letter-like patterns explicitly and that an explicit teaching method is preferred in mainstream primary education.     

幼儿对具体图片与抽象图片内隐记忆的实验研究

本研究选择３—６岁幼儿为被试,采用具体图片与抽象图片两种材料,分别交叉使用内隐学习与外显学习两种方式,探讨不同年龄幼儿内隐记忆与外显记忆的效果及特点。实验结果表明：幼儿期幼儿确实存在内隐学习,幼儿对抽象材料的内隐记忆效果优于外显记忆效果;幼儿内隐记忆与外显记忆两种效果均随年龄增长而逐步发展。