Dissociations of grammaticality and specific similarity effects in artificial grammar learning.

Three artificial grammar learning experiments investigated the memory processes underlying classification judgments. In Experiment 1, effects of grammaticality, specific item similarity, and chunk frequency were analogous between classification and recognition tasks. In Experiments 2A and 2B, instructions to exclude "old" and "similar" test items, under conditions that limited the role of conscious recollection, dissociated grammaticality and similarity effects in classification. Dividing attention at test also produced a dissociation in Experiment 3. It is concluded that a dual-process model of classification, whereby the grammaticality and specific similarity effects are based mostly on automatic and intentional memory processes, respectively, is consistent with the results, whereas a unitary mechanism account is not. This conclusion is further supported by evidence indicating that chunk frequency had both implicit and explicit influences on classification judgments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Indirect effects of synthetic grammar learning in an identification task.

Two experiments investigated the effects of incidental learning of an artificial grammar on an indirect measure. Ss memorized consonant strings and later identified these in a perceptual clarification procedure. The competitive chunking model by E. Servan-Schreiber and J. R. Anderson (see record 1990-27513-001) predicted faster identifications of grammatical as opposed to nongrammatical strings. Both experiments confirmed this prediction. Exp 2 further investigated whether faster identification induces a feeling of familiarity, which should increase the probability of subjects responding "grammatical" to a string. Faster identifications were indeed related to "old" responses in a recognition judgment. However, there was no systematic relation between speed of identification and grammaticality judgments, which is inconsistent with the prediction of the competitive chunking model that familiarity exclusively mediates grammaticality judgments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Synthetic grammar learning: Implicit rule abstraction or explicit fragmentary knowledge?

3 experiments were designed to demonstrate that classifying new letter strings as grammatical (i.e., conforming to a set of rules called a synthetic grammar) or ungrammatical may proceed from fragmentary conscious knowledge of the bigrams constituting the grammatical strings displayed in the study phase, rather than from an unconscious structured representation of the grammar, as A. S. Reber (see record 1989-38920-001) contended. In Experiment 1, grammaticality judgments of subjects initially studying grammatical letter strings did not differ from judgments by subjects learning from a list of the bigrams making up these strings. In Experiment 2, judgments about nongrammatical strings composed of valid bigrams placed in invalid locations were extremely poor, although better than chance. In Experiment 3 the explicit knowledge of bigrams as assessed by a recognition procedure appeared sufficient to account for observed performance on a standard test of grammaticality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A case of syntactical learning and judgment: How conscious and how abstract?

Examined 2 possible bases for grammatical judgments following syntactical learning: unconscious representations of a formal grammar, as in A. S. Reber's (see record 1976-21811-001) hypothesis of implicit learning, and conscious rules within information grammars. 50 undergraduates inspected strings generated by a finite-state grammar, viewed either one at a time or all at a time, with implicit or explicit learning instructions. 15 undergraduates served as controls. In a transfer test, Ss and controls judged the grammaticality of grammatical and nongrammatical strings and reported the bases for their judgments. Concurrent with previous results, Ss correctly classified a significant number of novel strings, indicating the operation of grammatical abstraction. However, reported rules predicted those grammatical judgments without significant residual. Ss acquired correlated grammars—personal sets of conscious rules, each of limited scope and many of imperfect validity. The rules embodied abstractions, consciously represented novelty that could account for abstraction embodied in judgments. It is argued that a better explanation of these results credits grammatical judgments to conscious rules within informal grammars rather than to unconscious representations of a formal grammar. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Artificial grammar learning depends on implicit acquisition of both abstract and exemplar-specific information.

The contributions of exemplar-specific and abstract knowledge to artificial grammar learning were examined in amnesic patients and controls. In Experiment 1, grammatical rule adherence and chunk strength exerted separate effects on grammaticality judgments. Amnesic patients exhibited intact classification performance, demonstrating the same pattern of results as controls. In Experiment 2, amnesic patients exhibited impaired declarative memory for chunks. In Experiment 3, both amnesic patients and controls exhibited transfer when tested with a letter set different than the one used for training, although performance was better when the same letter sets were used at training and test. The results suggest that individuals learn both abstract information about training items and exemplar-specific information about chunk strength and that both types of learning occur independently of declarative memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Names and words without meaning: Incidental postmorbid semantic learning in a person with extensive bilateral medial temporal damage.

The authors describe a densely amnesic man who has acquired explicit semantic knowledge of famous names and vocabulary words that entered popular culture after the onset of his amnesia. This new semantic knowledge was temporally graded and existed over and above the implicit memory he demonstrated in reading speed and accuracy, familiarity ratings, and his ability to make correct guesses on unfamiliar items. However, his postmorbid knowledge was limited to verbal labels denoting famous people and words; he possessed virtually no explicit knowledge of the meaning of these words or the identities of these individuals, although there was some evidence that some of this information had been acquired at an implicit level. Findings are discussed in the context of a neural network model (J. L. McClelland, B. L. McNaughton, & R. C. O'Reilly, 1995) of semantic acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of similarity in artificial grammar learning.

The authors examine the role of similarity in artificial grammar learning (AGL; A. S. Reber, 1989). A standard finite-state language was used to create stimuli that were arrangements of embedded geometric shapes (Experiment 1), connected lines (Experiment 2), and sequences of shapes (Experiment 3). Main effects for well-known predictors from the literature (grammaticality, associative global and anchor chunk strength, novel global and anchor chunk strength, length of items, and edit distance) were observed, thus replicating previous work. However, the authors extend previous research by using a widely known similarity-based exemplar model of categorization (the generalized context model; R. M. Nosofsky, 1989) to fit grammaticality judgments, by nested regression analyses. The results suggest that any explanation of AGL that is based on the existing theories is incomplete without a similarity process as well. Also, the results provide a foundation for further interpreting AGL in the wider context of categorization research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Impaired implicit learning in schizophrenia.

Schizophrenia patients consistently show deficits on tasks of explicit learning and memory. In contrast, their performance on implicit processing tasks often appears to be relatively intact, although most studies have focused on implicit learning of motor skills. This study evaluated implicit learning in 59 medicated schizophrenia outpatients and 43 controls using 2 different cognitive skill tasks. Participants completed a probabilistic classification task to assess procedural habit learning and an artificial grammar task to assess incidental learning of complex rule-based knowledge, as well as an explicit verbal learning and memory task. In addition to performing worse than controls on the explicit learning task, patients showed worse overall performance on the probabilistic classification task, which involves gradual learning through trial-by-trial performance feedback. However, patients and controls showed similar levels of learning on the artificial grammar task, suggesting a preserved ability to acquire complex rule-based knowledge in the absence of performance feedback. Discussion focuses on possible explanations for schizophrenia patients' poor probabilistic classification task performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Distinguishing Age Differences in Knowledge, Strategy Use, and Confidence During Strategic Skill Acquisition.

The authors examined how age differences in strategy selection are related to associative learning deficits and metacognitive variables, including memory ability confidence. In Experiment 1, increases in memory reliance for performance of the noun-pair lookup task were compared with increases in noun-pair memory ability. In Experiment 2, memory reliance was assessed for noun pairs memorized prior to the task. In each experiment, older adults manifested a substantial delay in transition to a retrieval-based strategy despite comparable noun-pair knowledge. In Experiment 3, young and older adults reported comparable confidence ratings for the accuracy of each memory probe response. However, older adults reported lower confidence in their general ability to use the memory retrieval strategy, which correlated with avoidance of the retrieval strategy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

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. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Qualitative differences between implicit and explicit sequence learning.

Four experiments investigate the differences between implicit and explicit sequence learning concerning their resilience to structural and superficial task changes. A superficial change that embedded the SRT task in the context of a selection task, while maintaining the sequence, did selectively hinder the expression of implicit learning. In contrast, a manipulation that maintained the task surface, but decreased the sequence validity, affected the expression of learning specifically when it was explicit. These results are discussed in the context of a dynamic framework (Cleeremans & Jime'nez, 2002), which assumes that implicit knowledge is specially affected by contextual factors and that, as knowledge becomes explicit, it allows for the development of relevant metaknowledge that modulates the expression of explicit knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Context, feedback, and the calibration and resolution of confidence in perceptual judgments

The effects of variations in the global task difficulty context on judgmental confidence and confidence calibration were investigated in two experiments requiring perceptual comparisons. In Experiment 1, target judgments of moderate difficulty were embedded in a larger set of more difficult (hard context) or less difficult (easy context) judgments. Decisional response time on the target items was longer in the hard context condition, but there was no effect of difficulty context on target judgment confidence, accuracy, over/underconfidence, calibration, or resolution. In Experiment 2, each subject was exposed to three levels of local judgment difficulty. The global contextual difficulty manipulation involved varying the frequency with which the hard and easy judgments appeared, and the presence or absence of trial-by-trial response feedback was manipulated between subjects. As in Experiment 1, contextual difficulty affected decisional response times but not mean confidence ratings or accuracy. However, we found that providing feedback on a globally difficult task makes calibration worse. Also, resolution (the ability to differentiate correct from incorrect judgments) was found to be superior for easy judgments in a difficult context and for difficult judgments in an easy context. We discuss the implication of these findings for research on confidence and confidence calibration.     

The information acquired during artificial grammar learning.

In an artificial grammar learning task, amnesic patients classified test items as well as normal Ss did. Item similarity did not affect grammaticality judgments when similar and nonsimilar test items were balanced for the frequency with which bigrams and trigrams (chunks) that appeared in the training set also appeared in the test items. Amnesic Ss performed like normal Ss. Results suggest that concrete information about letter chunks can influence grammaticality judgments and that this information is acquired implicitly. The similarity of whole test items to training items does not appear to affect grammaticality judgments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the relationship between recognition familiarity and perceptual fluency: evidence for distinct mnemonic processes

Fluent reprocessing of perceptual aspects of recently experienced stimuli is thought to support repetition priming effects on implicit perceptual memory tests. Although behavioral and neuropsychological dissociations demonstrate that separable mnemonic processes and neural substrates mediate implicit and explicit test performance, dual-process theories of memory posit that explicit recognition memory judgments may be based on familiarity derived from the same perceptual fluency that yields perceptual priming. Here we consider the relationship between familiarity-based recognition memory and implicit perceptual memory. A select review of the literature demonstrates that the fluency supporting implicit perceptual memory is functionally and anatomically distinct from that supporting recognition memory. In contrast to perceptual fluency, recognition familiarity is more sensitive to conceptual than to perceptual processing, and does not depend on modality-specific sensory cortices. Alternative possible relationships between familiarity in explicit memory and fluency in implicit memory are discussed.     

Visual Feature Learning in Artificial Grammar Classification.

The Artificial Grammar Learning task has been used extensively to assess individuals' implicit learning capabilities. Previous work suggests that participants implicitly acquire rule-based knowledge as well as exemplar-specific knowledge in this task. This study investigated whether exemplar-specific knowledge acquired in this task is based on the visual features of the exemplars. When a change in the font and case occurred between study and test, there was no effect on sensitivity to grammatical rules in classification judgments. However, such a change did virtually eliminate sensitivity to training frequencies of letter bigrams and trigrams (chunk strength) in classification judgments. Performance of a secondary task during study eliminated this font sensitivity and generally reduced the contribution of chunk strength knowledge. The results are consistent with the idea that perceptual fluency makes a contribution to artificial grammar judgments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Encoding fluency is a cue used for judgments about learning.

The authors used paired-associate learning to investigate the hypothesis that the speed of generating an interactive image (encoding fluency) influenced 2 metacognitive judgments: judgments of learning (JOLs) and quality of encoding ratings (QUEs). Results from Experiments 1 and 2 indicated that latency of a keypress indicating successful image formation was negatively related to both JOLs and QUEs even though latency was unrelated to recall. Experiment 3 demonstrated that when concrete and abstract items were mixed in a single list, latency was related to concreteness, judgments, and recall. However, item concreteness and fluency influenced judgments independently of one another. These outcomes suggest an important role of encoding fluency in the formation of metacognitive judgments about learning and future recall. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Savings in relearning: II. On the formation of behavior-based trait associations and inferences.

Five experiments based on Carlston and Skowronski's (1994) relearning paradigm suggest that people spontaneously derive trait knowledge about actors from behaviors but that this knowledge may reflect either explicit trait inference processes or implicit actor–trait associations. Experiments 1 and 2 found that inference-instructed and control Ss showed equivalent savings in subsequent efforts to learn actor–trait pairs but not when instructed Ss initially inferred the wrong trait. Experiment 3 showed that savings were equivalent for stimuli from different sources, and Experiment 4 showed that savings effects persisted even when the target was only incidentally associated with a stimulus behavior. Finally, Experiment 5 suggests that after several days, even explicit trait inferences can become inaccessible to intentional retrieval, although the earlier experiments show that they continue to exert an implicit effect on learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Artificial grammar learning depends on implicit acquisition of both abstract and exemplar-specific information": Correction.

Reports an error in the original article by B. J. Knowlton and L. R. Squire (Journal of Experimental Psychology: Learning, Memory, and Cognition, Vol 22[1], 169–181). The Appendix on page 181 contains several errors. The corrected Appendix is provided. (The following abstract of this article originally appeared in record 1996-02680-010). The contributions of exemplar-specific and abstract knowledge to artificial grammar learning were examined in amnesic patients and controls. In Experiment 1, grammatical rule adherence and chunk strength exerted separate effects in grammaticality judgments. Amnesic patients exhibited intact classification performance, demonstrating the same pattern of results as controls. In Experiment 2, amnesic patients exhibited impaired declarative memory for chunks. In Experiment 3, both amnesic patients and controls exhibited transfer when tested with a letter set different than the one used for training, although performance was better when the same letter sets were used at the training and test. The results suggest that individuals learn both abstract information about training items and exemplar-specific information about chunk strength and that both types of learning occur independently of declarative memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

What is learned from artificial grammars? Transfer tests of simple association.

Ss were trained on letter pairs or letter strings in an artificial grammar learning paradigm to determine the extent to which implicit learning is driven by simple associative knowledge. Learning on strings resulted in sensitivity to violations of grammaticality and in transfer to a changed letter set. Learning on letter pairs resulted in less sensitivity and no transfer. Discrepancies in performance were later reduced, but not eliminated, by equating the task demands of the conditions during learning. A direct test of associative knowledge showed that training on letter pairs resulted in knowledge of legal bigrams, but this knowledge was only weakly related to violation sensitivity. The experiments demonstrate that knowledge of isolated associations is sufficient to support some learning, but this knowledge cannot explain the more abstract knowledge that results from learning on complete exemplars. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Automaticity of Visual Statistical Learning.

The visual environment contains massive amounts of information involving the relations between objects in space and time, and recent studies of visual statistical learning (VSL) have suggested that this information can be automatically extracted by the visual system. The experiments reported in this article explore the automaticity of VSL in several ways, using both explicit familiarity and implicit response-time measures. The results demonstrate that (a) the input to VSL is gated by selective attention, (b) VSL is nevertheless an implicit process because it operates during a cover task and without awareness of the underlying statistical patterns, and (c) VSL constructs abstracted representations that are then invariant to changes in extraneous surface features. These results fuel the conclusion that VSL both is and is not automatic: It requires attention to select the relevant population of stimuli, but the resulting learning then occurs without intent or awareness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)