Differences in the types of musical regularity learnt in incidental- and intentional-learning conditions

Several studies have found learning of biconditional grammars only under intentional rule-search conditions (e.g., Johnstone & Shanks, 2001). Memorization of strings merely led to the learning of chunks. We used a musical grammar, a diatonic inversion, that is a type of biconditional grammar. Participants either were required to memorize a set of grammatical tunes (incidental learning), or were asked to search for the underlying rule whilst being given feedback about their performance (intentional learning). The results showed that participants in the incidental-learning condition did not learn the inversion rule and merely acquired explicit knowledge about chunks. However, participants in the intentional-learning condition learnt both the inversion rule and chunks.     

Differences in the types of musical regularity learnt in incidental- and intentional-learning conditions

Several studies have found learning of biconditional grammars only under intentional rule-search conditions (e.g., Johnstone & Shanks, 2001). Memorization of strings merely led to the learning of chunks. We used a musical grammar, a diatonic inversion, that is a type of biconditional grammar. Participants either were required to memorize a set of grammatical tunes (incidental learning), or were asked to search for the underlying rule whilst being given feedback about their performance (intentional learning). The results showed that participants in the incidental-learning condition did not learn the inversion rule and merely acquired explicit knowledge about chunks. However, participants in the intentional-learning condition learnt both the inversion rule and chunks.     

Visual statistical learning produces implicit and explicit knowledge about temporal order information and scene chunks: Evidence from direct and indirect measures

We examined whether visual statistical learning (VSL) produced implicit and/or explicit knowledge about temporal order information and scene chunks, using a rapid serial visual presentation target detection task and a two-alternative forced-choice (2AFC) familiarity test as indirect and direct measures of VSL, respectively. In the familiarization phase, participants viewed a visual stream of natural scenes consisting of four triplets (i.e., three images that always appeared in the same order). In the subsequent target detection task, participants were required to detect target items embedded in a stream of 12 images or 12 words representing each natural scene. In the final 2AFC familiarity test, participants observed two test sequences (statistically related triplets vs. unrelated foils) and decided whether the first or second sequence was more familiar based on the familiarization phase. In both test phases, we included the same (forward) and reverse (backward) order of scenes as presented during the familiarization phase to examine whether the expression of VSL was based on temporal order of scenes or scene chunks. The results of the target detection task showed a learning effect for both temporal order in the forward condition and chunks in the backward condition, irrespective of whether stimuli were images or words; in contrast, we did not observe a learning effect in the backward condition for scene images in the familiarity test. Our findings are compatible with a learning mechanism that has both implicit and explicit components based on temporal order information and scene chunks.     

先前知识经验对远距离水平映射规则内隐学习的限制

先前研究发现远距离规则能够被内隐地习得和迁移,表明内隐学习获得的知识是底层的抽象规则,那么这一抽象规则的习得和迁移是否会受到先前知识经验的限制?研究采用汉语声调的远距离水平映射规则为材料,通过创设不符合平仄知识经验的任意声调水平映射规则,在控制组块和重复结构等表面特征的条件下,探讨先前知识经验是否限制了远距离水平映射规则的内隐学习和迁移。结果发现相对于符合平仄知识经验的汉语声调水平映射规则,被试不能够内隐地习得和迁移任意声调的水平映射规则,表明先前知识经验在远距离水平映射规则内隐学习过程中发挥着重要作用。     

Implicit learning of semantic preferences of English words by Chinese learners

The aim of the present study was to explore whether Chinese learners could implicitly learn the semantic preferences of novel English words. In training, participants learned four novel verbs and were exposed to a set of verb-noun phrases that included these new words. What the participants were not told was that the use of the verbs depended on the concreteness of the nouns (i.e., the semantic preference rule). In testing, participants were required to choose between two possible verbs (one of which violated the semantic preference rule) for nouns that never occurred in training. The results showed that participants acquired unconscious knowledge of semantic preferences under incidental learning conditions, as measured by verbal reports and structural knowledge attributions. Our results provide further evidence for implicit learning of semantic preferences, suggesting that implicit learning is an important mechanism in the acquisition of L2 collocations.     

人工语法范式下的无意识知识探析

人工语法范式不仅是内隐学习领域广泛运用的范式,同时也是研究无意识知识的主要方法。文章通过对人工语法范式组成材料中的刺激频率、组块等方面进行深入探讨,不仅使人们对无意识知识有了更全面的认识,而且也有利于对内隐学习获得规则知识的假设提出更确定的回答;并通过对无意识知识的神经机制研究以及考察镜射规则学习过程的脑神经激活状况,获得了规则学习对应更为准确的脑神经活动,推动了人工语法范式下无意识知识的深入研究。     

Implicit learning of a recursive rule in an artificial grammar

Participants performed an artificial grammar learning task, in which the standard finite state grammar (J. Verb. Learn. Verb. Behavior 6 (1967) 855) was extended with a recursive rule generating self-embedded sequences. We studied the learnability of such a rule in two experiments. The results verify the general hypothesis that recursivity can be learned in an artificial grammar learning task. However this learning seems to be rather based on recognising chunks than on abstract rule induction. First, performance was better for strings with more than one level of self-embedding in the sequence, uncovering more clearly the self-embedding pattern. Second, the infinite repeatability of the recursive rule application was not spontaneously induced from the training, but it was when an additional cue about this possibility was given. Finally, participants were able to verbalise their knowledge of the fragments making up the sequences-especially in the crucial front and back positions-, whereas knowledge of the underlying structure, to the extent it was acquired, was not articulatable. The results are discussed in relation to previous studies on the implicit learnability of complex and abstract rules.     

Unconscious structural knowledge of tonal symmetry: Tang poetry redefines limits of implicit learning

The study aims to help characterize the sort of structures about which people can acquire unconscious knowledge. It is already well established that people can implicitly learn n-grams (chunks) and also repetition patterns. We explore the acquisition of unconscious structural knowledge of symmetry. Chinese Tang poetry uses a specific sort of mirror symmetry, an inversion rule with respect to the tones of characters in successive lines of verse. We show, using artificial poetry to control both n-gram structure and repetition patterns, that people can implicitly learn to discriminate inversions from non-inversions, presenting a challenge to existing models of implicit learning.     

汉语声调远距离规则的内隐学习及其迁移效应

内隐学习研究领域的一个重要问题是内隐学习获得的知识究竟是什么,即内隐学习获得的知识究竟是底层的抽象规则还是表面的特征.研究以汉语声调的远距离水平映射这一远距离规则为材料,通过对表面特征和底层规则之间的分离操作,在控制组块和重复结构等表面特征的条件下,探讨声调远距离规则的习得和迁移,结果发现被试能够内隐地习得和迁移汉语平仄声调的水平映射规则,证实了内隐学习确实能够获得底层的抽象规则,为内隐学习的抽象性问题提供了新的证据.     

Implicit learning of complex information in amnesia

Implicit learning abilities of nine amnesic patients were explored by using an artificial grammar learning task in which the test strings were constructed in such a way that grammaticality judgments could not be based on a simple knowledge of bigrams and trigrams (chunks). Results show that amnesic patients and controls performed at the same level during the classification task, whereas amnesic patients performed worse than controls in an explicit generation task. Moreover, there was no correlation between the implicit and explicit measures. These results are compatible with the existence of two kinds of representation intervening in artificial grammar learning. The first one based on processes leading to fragment-specific knowledge (the chunks, which can be accessed explicitly), and the second based on the learning of simple associations and more complex conditional relations between elements.     

内隐序列学习中转移组块的数量和位置效应

表征质量理论对意识增长持渐进观点,忽视新异刺激对意识的突变式影响;新异刺激理论强调意识突变,忽视新异刺激本身的表征质量增长。本研究采用经典确定性内隐序列学习范式,将转移组块作为新异刺激,操控其数量和位置,探究新异刺激如何通过表征质量来影响内隐学习和意识。结果表明：（1）数量效应显著,即两个转移组块更能促进内隐学习量,说明新异刺激本身需要足够的表征质量才能发挥“意外事件”的作用。（2）在位置效应上,两个转移组块且靠前的设置更能提高受控意识,表明第一个新异刺激必须出现在原序列初级表征质量阶段,才能使被试对新异刺激和原序列进行对比,加之第二个新异刺激的与之呼应,促进原序列意识增加。     

远距离规则的内隐学习使用了何种记忆存储器：来自神经网络模拟的证据

关于远距离规则的知识是如何被内隐学习的,研究尚未得出结论。该研究通过采用和人类被试相同的实验材料和程序,考察了简单循环网络模型（SRN）对两种汉语声调远距离规则——倒映和逆行规则的内隐学习。结果发现：1.在广泛的参数范围上,SRN能够学会倒映和逆行规则,表明模型的记忆缓冲器可以模拟人类远距离规则的内隐学习;2.SRN对倒映规则的学习比对逆行规则的学习更好,表明在功能上远距离规则的内隐学习可能优先使用了先进先出的记忆存储器及信息加工模式。该研究为探究远距离规则内隐学习的机制提供了新的证据和视角。     

Striatal activity in concept learning

Striatal learning systems have been implicated in learning relationships between visual stimuli and outcomes. In the present study, the activity of the striatum during visual concept learning in humans was examined by using functional magnetic resonance imaging (fMRI). Participants performed three concept-learning tasks and a baseline task. The participants were trained to criterion before fMRI scanning on two tasks, verbal and implicit. In the verbal task, classification could be performed on the basis of a simple verbal rule, but in the implicit task, there was no simple verbal rule. The novel-implicit learning task, in which an implicit structure was used, was not encountered by the participants before scanning. Across all three concept-learning tasks, there was significant activation in the striatum, in comparison with the baseline task. The striatum was recruited similarly in classification when the participants had different levels of expertise (novel-implicit vs. verbal and implicit) and were able to verbalize their learning to different degrees (verbal vs. implicit and novel-implicit). There was left lateral occipital activation when learning was implicit (implicit and novel-implicit), but not when learning was easily verbalized (verbal).     

Implicit learning of conjunctive rule sets: An alternative to artificial grammars

A single experiment is reported that investigated implicit learning using a conjunctive rule set applied to natural words. Participants memorized a training list consisting of words that were either rare-concrete and common-abstract or common-concrete and rare-abstract. At test, they were told of the rule set, but not told what it was. Instead, they were shown all four word types and asked to classify words as rule-consistent words or not. Participants classified the items above chance, but were unable to verbalize the rules, even when shown a list that included the categories that made up the conjunctive rule and asked to select them. Most participants identified familiarity as the reason for classifying the items as they did. An analysis of the materials demonstrated that conscious micro-rules (i.e., chunk knowledge) could not have driven performance. We propose that such materials offer an alternative to artificial grammar for studies of implicit learning.     

Performing the unexplainable: Implicit task performance reveals individually reliable sequence learning without explicit knowledge

Memory-impaired patients express intact implicit perceptual-motor sequence learning, but it has been difficult to obtain a similarly clear dissociation in healthy participants. When explicit memory is intact, participants acquire some explicit knowledge and performance improvements from implicit learning may be subtle. Therefore, it is difficult to determine whether performance exceeds what could be expected on the basis of the concomitant explicit knowledge. Using a challenging new sequence-learning task, robust implicit learning was found in healthy participants with virtually no associated explicit knowledge. Participants trained on a repeating sequence that was selected randomly from a set of five. On a performance test of all five sequences, performance was best on the trained sequence, and two-thirds of the participants exhibited individually reliable improvement (by chi-square analysis). Participants could not reliably indicate which sequence had been trained by either recognition or recall. Only by expressing their knowledge via performance were participants able to indicate which sequence they had learned.     

Implicit learning in rule induction and problem solving

Using the Chinese Ring Puzzle (Kotovsky & Simon, ; P. J. Reber & Kotovsky, ), we studied the effect on rule discovery of having to plan actions or not in order to reach a goal state. This was done by asking participants to predict legal moves as in implicit learning tasks (Experiment 1) and by asking participants to make legal moves as in problem-solving tasks (Experiment 2). Our hypothesis was that having a specific goal state to reach has a dual effect on rule discovery. The first effect is positive and related to feedback from moves done in order to attain the goal: generalising the results of action and associating them to the conditions in which they were obtained allows discovery of the rule and learning it. The second effect is negative. In attempting to reach a specific goal, participants first tend to reduce the distance that separates the current state from the goal state (hill climbing) and so neglect the kind of exploration that facilitates rule and procedure discovery because this would seem to be a detour from the goal. Results show that having to plan actions improved performance in implicit learning tasks (Experiment 1), yet it impaired performance in problem-solving tasks (Experiment 2). Although implicit learning and problem solving are based on rule discovery, and entail noticing regularities in the material, in both cases, rule discovery processes appear to be task-dependent.     

Prior familiarity with components enhances unconscious learning of relations

The influence of prior familiarity with components on the implicit learning of relations was examined using artificial grammar learning. Prior to training on grammar strings, participants were familiarised with either the novel symbols used to construct the strings or with irrelevant geometric shapes. Participants familiarised with the relevant symbols showed greater accuracy when judging the correctness of new grammar strings. Familiarity with elemental components did not increase conscious awareness of the basis for discriminations (structural knowledge) but increased accuracy even in its absence. The subjective familiarity of test strings predicted grammaticality judgments. However, prior exposure to relevant symbols did not increase overall test string familiarity or reliance on familiarity when making grammaticality judgments. Familiarity with the symbols increased the learning of relations between them (bigrams and trigrams) thus resulting in greater familiarity for grammatical versus ungrammatical strings. The results have important implications for models of implicit learning.     

Abstractionist and processing accounts of implicit learning

Five experiments evaluated the contributions of rule, exemplar, fragment, and episodic knowledge in artificial grammar learning using memorization versus hypothesis-testing training tasks. Strings of letters were generated from a biconditional grammar that allows different sources of responding to be unconfounded. There was no evidence that memorization led to passive abstraction of rules or encoding of whole training exemplars. Memorizers instead used explicit fragment knowledge to identify the grammatical status of test items, although this led to chance performance. Successful hypothesis-testers classified at near-perfect levels by processing training and test stimuli according to their rule structure. The results support the episodic-processing account of implicit and explicit learning.     

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.     

Contextual interference in implicit and explicit motor learning

The purposes of this study were to examine the contextual interference effect in implicit learning and to compare implicit and explicit learning. Thirty-two participants performed a pursuit-tracking task for 60 acquisition and ten retention trials. The middle segment of target pathways had only two patterns whereas other segments had random patterns. A combination of awareness and practice order for the middle segment created four acquisition conditions: implicit-blocked, implicit-serial, explicit-blocked and explicit-serial. A questionnaire and a recognition test revealed that implicit groups were unaware of the repetition. Results showed no contextual interference effect in either implicit or explicit learning. Acquisition and retention performances were better for the middle segment than the other segments regardless of awareness. No difference between the implicit and explicit groups was found, suggesting that the implicit learning condition led to learning equivalent to the explicit learning condition.