Article

Characteristics of Dissociable Human Learning Systems

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  • Pacific Science & Engineering, San Diego, United States
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Abstract

A number of ways of taxonomizing human learning have been proposed. We examine the evidence for one such proposal, namely, that there exist independent explicit and implicit learning systems. This combines two further distinctions, (1) between learning that takes place with versus without concurrent awareness, and (2) between learning that involves the encoding of instances (or fragments) versus the induction of abstract rules or hypotheses. Implicit learning is assumed to involve unconscious rule learning. We examine the evidence for implicit learning derived from subliminal learning, conditioning, artificial grammar learning, instrumental learning, and reaction times in sequence learning. We conclude that unconscious learning has not been satisfactorily established in any of these areas. The assumption that learning in some of these tasks (e.g., artificial grammar learning) is predominantly based on rule abstraction is questionable. When subjects cannot report the “implicitly learned” rules that govern stimulus selection, this is often because their knowledge consists of instances or fragments of the training stimuli rather than rules. In contrast to the distinction between conscious and unconscious learning, the distinction between instance and rule learning is a sound and meaningful way of taxonomizing human learning. We discuss various computational models of these two forms of learning.

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... For example, it was found that participants could transfer grammatical knowledge about memorised strings to novel instances (Mathews, 1990;Cleeremans, 1993;Knowlton and Squire, 1996), even novel instances in different modalities (Altmann et al., 1995;Dienes et al., 1999). However, this "abstractionist" view has been questioned by considerable research (Perruchet and Pacteau, 1990;Brooks and Vokey, 1991;Vokey and Brooks, 1992;Shanks and St John, 1994). For example, it was demonstrated that the transfer effect in AGL was based on the similarity between novel strings and the "whole exemplar" stored in memory during training or explicitly memorised fragments or chunks of materials (Dulany et al., 1984;Mathews et al., 1989;Perruchet and Pacteau, 1990). ...
... However, these findings seem inconsistent to some previous studies that suggested that abstract structure could be acquired only in explicit learning conditions (Shanks and St John, 1994;Dominey and Jeannerod, 1997;Gomez, 1997;Dominey et al., 1998;Boyer et al., 2005). For example, Dominey et al. (1998) demonstrated that surface structures can be acquired by either implicit or explicit learners, but learning abstract structures could occur only for explicit learners. ...
... Moreover, the present findings also helped account for the inconsistent findings about abstract learning and consciousness. Although more recent studies have provided new evidence that abstract learning can occur unconsciously (Dienes et al., 2012;Kemeny and Meier, 2016;Huang et al., 2017;Ling et al., 2018), other studies supported that abstract knowledge can only be acquired consciously (Shanks and St John, 1994;Dominey et al., 1998;Boyer et al., 2005;Cleeremans and Destrebecqz, 2005). According to our findings, this might be because the former studies used relatively simple abstract structures while the latter studies used more complex structures. ...
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Although many studies have provided evidence that abstract knowledge can be acquired in artificial grammar learning, it remains unclear how abstract knowledge can be attained in sequence learning. To address this issue, we proposed a dual simple recurrent network (DSRN) model that includes a surface SRN encoding and predicting the surface properties of stimuli and an abstract SRN encoding and predicting the abstract properties of stimuli. The results of Simulations 1 and 2 showed that the DSRN model can account for learning effects in the serial reaction time (SRT) task under different conditions, and the manipulation of the contribution weight of each SRN accounted for the contribution of conscious and unconscious processes in inclusion and exclusion tests in previous studies. The results of human performance in Simulation 3 provided further evidence that people can implicitly learn both chunking and abstract knowledge in sequence learning, and the results of Simulation 3 confirmed that the DSRN model can account for how people implicitly acquire the two types of knowledge in sequence learning. These findings extend the learning ability of the SRN model and help understand how different types of knowledge can be acquired implicitly in sequence learning.
... En este sentido, la primera aclaración sobre los procesos implícitos es que, si bien la evidencia proveniente de las áreas de memoria y aprendizaje apoya su existencia, esta no confirma que sean procesos inconscientes, por lo que además de impreciso es irrelevante caracterizarlos de este modo (Newell & Shanks, 2014;Shanks & St. John, 1994). Debido a esto, por ejemplo, es incorrecto sostener que los procedimientos de primado ampliamente usados en memoria puedan medir procesos inconscientes, dado que su ejecución demanda atención focalizada y, por lo tanto, procesos controlados y conscientes (Banse & Greenwald, 2007). ...
... Por último, el criterio de confiabilidad indica que debe evitarse que la medida directa se contamine por variables que no estén relacionadas con el comportamiento determinante de la medida indirecta; no obstante, el reporte verbal se ve afectado por variables como la deseabilidad social o la aquiescencia (Shanks, 2005;Shanks & St. John, 1994). ...
... No obstante, teniendo en cuenta las limitaciones del reporte verbal como indicador de consciencia, las pruebas directas deben tener en cuenta los criterios de relevancia, sensibilidad, inmediatez y confiabilidad. De no cumplirse estos criterios, las interpretaciones de las disociaciones pueden verse comprometidas (Newell & Shanks, 2014;Shanks, 2005Shanks, , 2017Shanks & St John, 1994). ...
Article
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La investigación en cognición implícita ha aumentado de manera vertiginosa durante las últimas décadas, principalmente por el uso generalizado de procedimientos experimentales conocidos como medidas implícitas. A diferencia de los cuestionarios de autoinforme, estas metodologías impiden que sesgos como la deseabilidad social afecten las respuestas de los participantes, lo que permite abordar temas sensibles. Sin embargo, las medidas implícitas difieren en aspectos como las instrucciones, los materiales o los indicadores conductuales analizados. Debido a esto, hay controversia sobre la naturaleza de los procesos que están siendo medidos, las características que se les atribuyen y, por ende, la posibilidad de hacer comparaciones entre los estudios que emplean diferentes medidas implícitas. Basándose en un modelo de procesamiento dual, este trabajo propone que las medidas implícitas pueden entenderse como indicadores de procesos automáticos. A partir de dicha propuesta, se discuten los requisitos que las medidas implícitas deben cumplir y algunos desafíos para la investigación en automaticidad.
... The second theoretical approach, controlled application of conscious knowledge, is supported by researchers who argue that consciousness is needed for representations to arise even if they are these representations are supported by mechanisms which are themselves unconscious (Dulany, 1997;Perruchet & Vinter, 2002;Shanks & John, 1994). The third theoretical approach, controlled application of unconscious knowledge, is held by authors who view implicitness of learning as existing on a spectrum between completely conscious and completely unconscious (Mangan, 2003; M. C. Price & Norman, 2008). ...
... As there are multiple domains of explicit cognition, such as processing speed, intelligence, memory, and learning, so too are there multiple domains of implicit cognition. Differences and dissociations between implicit and explicit processing have been explored in many different areas of investigation, such as perception (Reingold & Merikle, 1988), memory (Kinoshita, 2001), learning (Shanks & John, 1994), and conditioning (Clark & Squire, 1998). The focus of the current thesis was on implicit learning and memory and the level of commonality that is shared between the different task outcomes -these task outcomes being operationalised representations of different implicit processes. ...
... If the first factor represented a common implicit ability, then it is likely that the second factor represented an ability similar to competitive-chunking, which is suggested to be the underlying strategy by which high-chunk items are learned (Orbán et al., 2008). The unattended condition of the VSL task loaded on neither the first nor second factor; this was expected based on the intended explicit nature of the processes involved in this condition (Turk-Browne et al., 2005), and adds some strength to the claim that the first factor was indeed a representation of a common implicit ability based on the dissociable nature of the two cognitive types (Jin, 2014;Shanks & John, 1994). Similar to the unattended arm of the VSL, the priming scores loaded strongly on neither factor, although it was slightly stronger than the former outcome on the first factor. ...
Thesis
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Is there is a common implicit ability analogous to I.Q. (i.e., a latent factor determined by strong inter correlations of psychometric measures)? Based on my Ph.D. research, there is just enough evidence to argue both ways.
... These latter findings suggest a collaborative process between implicit and explicit memory systems during offline learning that is dependent on sleep. However, these results were obtained using implicit and explicit measures that are not comparable (cf. the study by Shanks & St. John, 1994). In particular, the generation task used to assess explicit knowledge does not necessarily tap the same knowledge base used to evaluate implicit memory, which is based on RT. ...
... Our experimental design was based on the criteria proposed by Newell and Shanks (2014) and Shanks and St. John (1994) to evaluate the awareness of sequential knowledge. According to these criteria, explicit measures need to be: 1) reliable and resistant to the influence of social desirability, 2) presented as concurrently as possible to the implicit task, 3) relevant, that is, directly related to performance in the implicit task, 4) sensitive, that is, presented in conditions similar or identical to the settings in which implicit learning took place, and 5) activated by cues similar to those used in the implicit task. ...
... These results are consistent with the previous ideas of Fischer et al. (2006), who found that cooperation between implicit and explicit memory occurs during sleep. Our study confirms and extends those results using an experimental SRTT in which these two measures are made comparable according to the criteria suggested by Shanks and St. John (1994) and Newell and Shanks (2014). ...
Article
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This laboratory study explores whether sleep has different effects on explicit (recognition-based) and implicit (priming-based) memory. Eighty-nine healthy participants were randomly assigned to one of two experimental conditions: sleep or wake. All participants were previously exposed to an incidental learning session involving a 12-element deterministic second-order conditional sequence embedded in a serial reaction time task. The participants' explicit and implicit knowledge was assessed both immediately after the learning session (pretest) and after 12 h (posttest). For the sleep group, participants had a night of normal sleep between pretest and posttest, whereas the wake group spent 12 h awake during the day. The measures involved an explicit recognition test and an implicit priming reaction-time test with old fragments from a previously learned sequence and new fragments of a different control sequence. The sleep group showed statistically significant improvement between the pretest and the posttest in the explicit memory measure, whereas the wake group did not. In the implicit task, both groups improved similarly after a 12-h retention interval. These results suggest that throughout sleep, implicitly acquired information is processed offline to yield an explicit representation of knowledge incidentally acquired the night before.
... A frequently debated issue in the statistical learning literature is the role of awareness in learning (Cleeremans, Destrebecqz, & Boyer, 1998;Frensch & Rünger, 2003;Shanks, 2005;Shanks & St John, 1994). Interestingly, the learning effects observed in the colour-word contingency learning procedure seem to be by nature primarily implicit. ...
... It is also less likely that participants learned the regularities explicitly, but only in a fragmentary way. In the colour-word contingency learning task, the regularities are already simple (word-colour pairings), unlike, for example, in sequence learning where it is possible that only part of a sequence has been learned (Shanks & St John, 1994). In any case, it is clear that awareness in the colour-word contingency learning task is not substantial. ...
Article
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In this article, I review research on incidental learning of simple stimulus-response regularities. The article summarizes work with the colour-word contingency learning paradigm and related simple learning procedures. In the colour-word contingency learning paradigm participants are presented with a coloured neutral word on each trial and are asked to ignore the word and respond to the print colour (e.g., similar to a Stroop procedure). Distracting words are typically colour-unrelated neutral stimuli. However, each distracting word is presented most often in one target colour (e.g., "move" most often in blue, "sent" most often in green, etc.). Learning of these contingencies is indicated by faster and more accurate responses to high contingency trials (in which the word is presented with its frequent colour) relative to low contingency trials. This procedure has proven useful for investigations in incidental learning. The present manuscript summarizes the existing work with this (and related) learning procedures and highlights emerging directions.
... The use of retrospective verbal reporting is not without problems, however. It has been suggested that it may not be the most appropriate way to detect implicit knowledge, on the basis of what Shanks and St. John (1994) call the Sensitivity and Information criteria. By sensitivity, they mean that a measure of awareness needs to be sensitive enough to detect as much conscious knowledge as possible. ...
... Retrospective verbal reports, which we used to measure rule awareness in our study, have been criticised for potentially not being sensitive enough to conscious knowledge. Specifically, the concern is that there may be underreporting of conscious knowledge, if participants are not confident or unable to accurately report the content of their knowledge (Rebuschat, 2013;Shanks and St. John, 1994). To address this point, we tried to make our questionnaire as sensitive as possible by including multiple indirect questions aimed at probing participants' knowledge of the rule, by asking participants to provide a translation of the novel prepositions as well as providing their impressions on preposition usage (Appendix A). ...
Thesis
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Language proficiency largely relies on implicit knowledge, which is unconscious and operates independently of voluntary control. Implicit learning is a process of incidental learning which results in the acquisition of implicit knowledge. We know that adult learners can acquire knowledge of novel L2 linguistic rules through implicit learning, as evidenced by their performance on receptive tasks. However, it is unclear whether implicit learning processes can also support the development of L2 production skills. The central question of this dissertation was whether it would be possible for learners to acquire implicit knowledge of a new rule through implicit learning and use it directly in spoken production. Our second question concerns the relationship between production and comprehension: we asked whether implicit knowledge acquired through a production task would also lead to improved performance in comprehension. To address these questions, we trained participants on a semiartificial language based on a rule naturally found in Czech: specifically, the usage rule for a pair of spatial prepositions (v and na) which alternate depending on the distinction between open and enclosed spaces. Training was carried out using a novel methodology based on elicited oral imitation, which was also used to test productive knowledge. Participants were also tested on comprehension, using both reaction time and recognition memory paradigms. Our findings suggest that it is possible to acquire implicit productive knowledge through a production-based task, and to generalise it to new instances in spoken production. The results of our experiments also show that learning outcomes were sensitive to the specific procedure used to train participants, which appeared to interact with individual differences in working memory. Finally, we found limited evidence that implicit knowledge acquired through production could be transferred to comprehension, supporting a skill-specific account of implicit knowledge.
... This approach, also adopted in the Pessiglione et al study, can be rectified in two ways. One is to ensure that the methods to assess awareness are relevant and sensitive (Berry & Dienes, 1993;Shanks, 2017;Shanks & St. John, 1994). This could be achieved by, for instance, a closer similarity between the awareness test and the measure of interest. ...
... If instrumental learning does indeed require conscious access to proceed, the earlier results supporting unconscious instrumental learning may have resulted from transient moments of awareness during the learning task contributing to the unconscious knowledge. Those may have been undetected due to lack of immediate, sensitive measures (Berry & Dienes, 1993;Newell & Shanks, 2013;Shanks & St. John, 1994), such as trial-by-trial awareness checks. In the two experiments reported here, it was evident that most participants were aware of the nature of the stimuli on at least some of the trials, and that there are individual differences in those proportions. ...
Article
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Instrumental conditioning is a crucial substrate of adaptive behaviour, allowing individuals to selectively interact with the stimuli in their environment to maximise benefit and minimise harm. The extent to which complex forms of learning, such as instrumental conditioning, are possible without conscious awareness is a topic of considerable importance and ongoing debate. In light of recent theoretical and empirical contributions casting doubt on the early demonstrations of unconscious instrumental conditioning, we revisit the question of its feasibility in two modes of conditioning. In Experiment 1, we used trace conditioning, following a prominent paradigm (Pessiglione et al., 2008) and enhancing its sensitivity. Success in this task requires participants to learn to approach reward-predictive stimuli and avoid punishment-predictive stimuli through monetary reinforcement. All stimuli were rendered unconscious using forward-backward masking. In Experiment 2, we used delay conditioning to shorten the stimulus-outcome delay, retaining the structure of the original task but presenting the stimuli under continuous flash suppression to allow for an overlap of the stimulus, action, and outcome, as well as replacing monetary reinforcement with primary appetitive reinforcement. In both experiments, we found evidence for absence of unconscious instrumental conditioning, showing that participants were unable to learn to adjust their behaviour to approach positive stimuli and avoid negative ones. This result is consistent with evidence that unconscious stimuli fail to bring about long-term behavioural adaptations, and provides empirical evidence to support theoretical proposals that consciousness might be necessary for adaptive behaviour, where selective action is required.
... The results of verbal reports can be used to group participants dichotomously as being "aware" or "unaware" of the underlying rule system (e.g., Williams, 2005) or along a continuum based on the amount of information they are able to report (Brooks & Kempe, 2013). Several researchers (e.g., Shanks & St. John, 1994) have challenged the interpretation of a lack of verbalization in retrospective verbal reports as indicative of implicit knowledge. For instance, participants may choose to withhold information for a number of different reasons, such as lacking the meta-language needed to describe linguistic rules or regularities (Hamrick & Sachs, 2018). ...
... In other words, when using guess, intuition, memory, or rule as the possible attributions, guess and intuition would reflect no or a relatively low level of awareness, whereas memory or rule might reflect a higher level of awareness. Although direct and indirect tests have been argued to be more sensitive than retrospective verbal reports in disentangling implicit and explicit knowledge (Shanks & St. John, 1994), these tests are not without their limitations. To illustrate, untimed GJTs are argued to be reflective of explicit knowledge, and timed GJTs are argued to be reflective of implicit knowledge (Ellis et al., 2009). ...
... Neither of these theories specifically account for implicit processes important for motor skill learning, and research on the benefits of interleaving has largely ignored the interplay between implicit and explicit learning (Bjork & Kroll, 2015;Shanks & St. John, 1994). In light of this, an alternate theory has emerged that proposes that high CI and increased task switching overloads an individual's working memory capacity, preventing them from gaining explicit task-relevant knowledge (Rendell et al., 2011) and enabling greater implicit learning. ...
... To assess whether subjects had acquired explicit knowledge of the sequences, a free-recall questionnaire based on past research was administered after the second session (Robertson et al., 2004;Willingham & Goedert-Eschmann, 1999). Though free recall may also reflect a degree of implicit memory, that is also true of most explicit awareness tests (Shanks & St. John, 1994). Though there is no consensus on the best way to measure awareness in this task (Robertson, 2007), free recall, rather than recognition, was assessed as it can be argued that it is the most appropriate measure of explicit memory (Frensch & Rünger, 2003). ...
Article
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Compared to blocked practice, interleaved practice of different tasks leads to superior long-term retention despite poorer initial acquisition performance. This phenomenon, the contextual interference effect, is well documented in various domains but it is not yet clear if it persists in the absence of explicit knowledge in terms of fine motor sequence learning. Additionally, while there is some evidence that interleaved practice leads to improved transfer of learning to similar actions, transfer of implicit motor sequence learning has not been explored. The present studies used a serial reaction time task where participants practiced three different eight-item sequences that were either interleaved or blocked on Day 1 (training) and Day 2 (testing). In Experiment 1, the retention of the three training sequences was tested on Day 2 and in Experiment 2, three novel sequences were performed on Day 2 to measure transfer. We assessed whether subjects were aware of the sequences to determine whether the benefit of interleaved practice extends to implicitly learned sequences. Even for participants who reported no awareness of the sequences, interleaving led to a benefit for both retention and transfer compared to participants who practiced blocked sequences. Those who trained with blocked sequences were left unprepared for interleaved sequences at test, while those who trained with interleaved sequences were unaffected by testing condition, revealing that learning resulting from blocked practice may be less flexible and more vulnerable to testing conditions. These results indicate that the benefit of interleaved practice extends to implicit motor sequence learning and transfer.
... One possible reason for the differing results concerning offline consolidation across studies might be an uncontrolled explicit component in the implicit SRTT (Moisello et al., 2009;Shanks & Johnstone, 1999;Shanks & St John, 1994;Wilkinson & Shanks, 2004). It is common practice to assess the level of explicit awareness of the sequence with a questionnaire and to exclude data from participants who correctly recalled a number of consecutive elements of the sequence above a fixed cutoff (Brown, Robertson, & Press, 2009;Press et al., 2005;Robertson et al., 2004;Sami et al., 2014;Willingham & Goedert-Eschmann, 1999). ...
... However, this approach can be problematic because the remaining participants potentially form a heterogeneous group. In particular, it could include participants that had explicit knowledge just below the cutoff, participants in whom the memory of the sequence faded by the end of the experiment, or participants with intermediate levels of awareness between implicit and explicit learning, i.e. fringe consciousness (Norman, Price, & Duff, 2006;Shanks & St John, 1994;Wilkinson & Jahanshahi, 2007). Furthermore, in some studies using the SRTT, participants who became aware of the sequence were not separated from those who did not (Martini, Furtner, & Sachse, 2013;Nissen & Bullemer, 1987;Willingham & Goedert-Eschmann, 1999). ...
Article
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The serial reaction time task (SRTT) has been widely used to induce learning of a repeated motor sequence without the participants’ awareness. The task has also been of major influence for defining current concepts of offline consolidation after motor learning. The present study intended to replicate previous findings in a larger population of 53 healthy individuals. We were unable to reproduce previous results of online and offline implicit motor learning with the SRTT. Trials with a repeated sequence rapidly induced shorter reaction times compared to random trials, but this improvement was lost in a post-test obtained a few minutes after the training block. Furthermore, no offline consolidation was observed as there was no change in sequence specific reaction time gain between the post-test immediately after training and a re-test obtained 8 hours after training. Online or offline learning remained absent when we modulated the number of sequence repetitions, the error levels, and the structure of random sequences. We conclude that the SRTT induces a rapid and temporary adaptation to the sequence rather than learning, since the repeated motor sequence does not seem to be encoded in memory.
... According to the earlier Reber's view, people can abstract general structures across grammatical exemplars and apply them in the test phase (Reber, 1969;Reber & Lewis, 1977). However, several researchers suggested an alternative explanation of classification performance by which it processed similar to implicit memory: participants categorize items as grammatical or ungrammatical based on their similarity to specific training items (Shanks & St. John, 1994;Perruchet & Pacteau, 1990) or on specific fragments of them (Vokey & Brooks, 1992). This similarity-based approach fits more with fluency effects. ...
Article
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The heuristic of information processing fluency plays an important role in making judgments. Some sources of processing fluency can be relevant or irrelevant to the content of a judgment. In this study, we aim to check whether individuals can distinguish different sources of fluency or fluency has a general effect on judgments. We used an artificial grammar learning paradigm (AGL) and tested the effects of different fluency sources (grammaticality and perceptual noise) on the judgment of grammaticality or of subjective ease of reading. It was found that both grammaticality and perceptual noise affected grammaticality judgements: the grammatical and the less noisy strings were evaluated more often as grammatical. However, only the perceptual noise affected judgments of subjective ease of reading. The results obtained provide evidence that fluency may contribute to the effects of implicit learning. It is possible that the processing fluency heuristic is the additional factor of judgement in the lack of explicit knowledge. Perhaps, perceptual noise provided almost complete explicit information for judgment of ease of reading; hence there was no need for additional heuristics. Another possible explanation is that perceptual fluency sources affect the early stages of information processing in a mandatory manner, unlike the conceptual ones. Overall, results are better explained by the non-specificity fluency hypothesis supporting the impossibility to distinguish between different fluency sources.
... It is important to emphasize that procedural (implicit) learning tasks are not process pure (e.g., Cleeremans, Destrebecqz, & Boyer, 1998;Reber, 1989;Shanks & St. John, 1994). For example, performance on artificial grammar and serial reaction time tasks may reflect conscious learning of fragmentary chunks of information (Buchner, Steffens, Erdfelder, & Rothkegel, 1997;Perruchet & Pacteau, 1990). ...
Article
Impaired procedural learning has been suggested as a possible cause of developmental dyslexia (DD) and developmental language disorder (DLD). We evaluate this theory by performing a series of meta-analyses on evidence from the six procedural learning tasks that have most commonly been used to test this theory: the serial reaction time, Hebb learning, artificial grammar and statistical learning, weather prediction, and contextual cuing tasks. Studies using serial reaction time and Hebb learning tasks yielded small group deficits in comparisons between language impaired and typically developing controls (g = -.30 and -.32, respectively). However, a meta-analysis of correlational studies showed that the serial reaction time task was not a reliable correlate of language-related ability in unselected samples (r = .03). Larger group deficits were, however, found in studies using artificial grammar and statistical learning tasks (g = -.48) and the weather prediction task (g = -.63). Possible reasons for the discrepancy in results from different tasks that all purportedly measure procedural learning are highlighted. We conclude that current data do not provide an adequate test of the theory that a generalized procedural learning deficit is a causal risk factor for developmental dyslexia or developmental language disorder. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
... The utility of using questionnaires to establish awareness and varying the introduction of cursor rotations to manipulate participants' awareness of the visuomotor distortion have been shown to be problematic. Verbal reports tend to underestimate participants' awareness, possibly due to differences in retrieval contexts between motor and verbal responses [36]. As well, verbal reports may not exhaustively establish a participant's level of awareness, given the insensitivity of verbal assessment methods to establish knowledge held with low confidence [37][38][39][40]. ...
Article
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Reaching with a visuomotor distortion in a virtual environment leads to reach adaptation in the trained hand, and in the untrained hand. In the current study we asked if reach adaptation in the untrained (right) hand is due to transfer of explicit adaptation (EA; strategic changes in reaches) and/or implicit adaptation (IA; unconscious changes in reaches) from the trained (left) hand, and if this transfer changes depending on instructions provided. We further asked if EA and IA are retained in both the trained and untrained hands. Participants (n = 60) were divided into 3 groups (Instructed (provided with instructions on how to counteract the visuomotor distortion), Non-Instructed (no instructions provided), and Control (EA not assessed)). EA and IA were assessed in both the trained and untrained hands immediately following rotated reach training with a 40° visuomotor distortion, and again 24 hours later by having participants reach in the absence of cursor feedback. Participants were to reach (1) so that the cursor landed on the target (EA + IA), and (2) so that their hand landed on the target (IA). Results revealed that, while initial EA observed in the trained hand was greater for the Instructed versus Non-Instructed group, the full extent of EA transferred between hands for both groups and was retained across days. IA observed in the trained hand was greatest in the Non-Instructed group. However, IA did not significantly transfer between hands for any of the three groups. Limited retention of IA was observed in the trained hand. Together, these results suggest that while initial EA and IA in the trained hand are dependent on instructions provided, transfer and retention of visuomotor adaptation to a large visuomotor distortion are driven almost exclusively by EA.
... Second, participants were asked to describe strategies without any strings being physically present, necessitating reliance on prior memories (which may not have been equally encoded across participants). These features collectively undermine our task's sensitivity and informational relevance as we could not estimate whether evaluative strategies varied across individual strings(Shanks & John, 1994). At best, our awareness levels represent differences in extant knowledge of global evaluative strategies. ...
... Implicit learning seems to function like a sponge, soaking up regularities in the environment uncritically. A problem with defining implicit learning is that it is defined by negatives, no awareness of the fact that learning took place nor of the resulting knowledge, and a negative can be hard to prove (Shanks & St John, 1994), see the General Discussion for more. Nevertheless, for the experiments in the current thesis we used the most common characterizations of implicit learning: no awareness of what is to be learned and no awareness of the resulting knowledge. ...
Thesis
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Predictability is increasingly recognized as an important principle in perception and motor learning. The pursuit of increased predictability seems to one of the main goals that the human system pursues. Therefore, providing predictability in one of the most challenging situations that humans face, namely multitasking, a promising line of research. In this thesis the impact of predictability was systematically investigated in five experiments. In the first four experiments predictability was achieved by implementing a repeating pattern in one task, or both tasks. Participants acquired knowledge of these patterns either explicitly or implicitly in several training sessions, under single-task or dual-task conditions. We tested whether this increased predictability helped dual-task performance after the training sessions. The results suggest that predictability is helpful for dual-task performance, although the benefits are confined to the predictable task itself. In a fifth experiment we focused on providing between task predictability, which led to a large performance improvement in both tasks, prompting the discussion about what constitutes a task, in the sense of when can two tasks be perceived as a single task comprising both, a theoretical problem we tried to tackle in one of the articles. Explanations for the findings, theoretical implications, methodological issues and suggestions for future research are given in the general discussion
... Note that the hypothesis that L2 promotes deliberation is not always supported; for example, recent evidence demonstrates that deliberate reasoning not only is not always facilitated in L2 but is sometimes even hindered (Białek et al. 2020;Hadjichristidis, Geipel, and Keysar 2019a). Applied to learning and EC, the dual-processes theories suggest that the implicit system is able to learn without awareness (Gawronski and Bodenhausen 2006;Shanks and St John 1994). Although more recent models would rather support the idea that various processes are at task during EC (Kruglanski and Gigerenzer 2011;Mitchell, De Houwer, and Lovibond 2009), our results are in line with the argument that L2 promotes explicit over implicit processes, since EC was sensitive to explicit memory of the US in L2 but not in L1. ...
Article
Our preferences and evaluations are often affected by contextual factors. One unavoidable context is language. We used an evaluative conditioning (EC) paradigm (pairing neutral stimuli with emotional or neutral stimuli) to investigate whether our evaluations are equally conditioned in a first (L1) and a second language (L2). An EC effect was observed in both languages, however, if in L1 it occurred independently of recollection of the pairing of the stimuli, in second language memory seemed to play a larger role. These results were confirmed using a more implicit measure (memory confusion paradigm). Overall, the results suggest that conditioning occurs both in L1 and L2 but is weaker and more sensitive to memory of the emotional stimuli in L2. The study is the first demonstration that EC is modulated by language and converges with recent findings showing that linguistic context can modulate our behaviours.
... However, Hama and Leow trained and tested participants on auditory items, while Rebuschat et al. did so with written items (for a recent overview, see Kim & Godfroid, 2019). It is well known that modality makes a difference in memory recall (Shanks & St. John, 1994), and there is recent evidence suggesting that modality also plays a key role in implicit learning (Frost, Armstrong, Siegelman, & Christiansen, 2015). However, there is a scarcity of studies that directly investigate how input modality might affect the learning of a novel language in adulthood. ...
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There is conflicting empirical evidence regarding the role of awareness in second language learning. Possible explanations for the contradictory results include the modality in the exposure and assessment phases of previous experiments. Our study investigated the acquisition of a novel determiner system under incidental exposure conditions and examined the effect of modality in both exposure and assessment phases. Animacy served as a hidden regularity in the determiners which were embedded in sentences and presented to Chinese speakers of English either in auditory or visual mode. Learning was assessed by a two-alternative forced-choice test either auditorily or in writing. Implicit and explicit knowledge were measured using retrospective verbal reports and source judgements. Bayesian analysis provided moderate evidence for above chance level learning. Significant learning effects were observed regardless of whether participants based their accuracy judgements on explicit or implicit knowledge. Bayesian analysis showed moderate evidence for above chance learning effects for aware participants. Generalized linear mixed-effects modelling revealed a small-size significant benefit of the auditory exposure modality over the written modality but indicated no significant effect of the modality of assessment or awareness. Our research underscores the importance of considering the role of modality of exposure in incidental L2 learning contexts.
... Transfer-appropriate processing. The differential power of the two tests to reveal evidence of explicit contextual facilitation may be best understood within the transfer-appropriate processing (TAP) framework [23][24][25] . According to this framework, the 'success' of the single memory system in facilitating conscious performance critically depends on the match of information required in the search and conscious-awareness tasks. ...
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Visual search is facilitated when observers encounter targets in repeated display arrangements. This ‘contextual-cueing’ (CC) effect is attributed to incidental learning of spatial distractor-target relations. Prior work has typically used only one recognition measure (administered after the search task) to establish whether CC is based on implicit or explicit memory of repeated displays, with the outcome depending on the diagnostic accuracy of the test. The present study compared two explicit memory tests to tackle this issue: yes/no recognition of a given search display as repeated versus generation of the quadrant in which the target (which was replaced by a distractor) had been located during the search task, thus closely matching the processes involved in performing the search. While repeated displays elicited a CC effect in the search task, both tests revealed above-chance knowledge of repeated displays, though explicit-memory accuracy and its correlation with contextual facilitation in the search task were more pronounced for the generation task. These findings argue in favor of a one-system, explicit-memory account of CC. Further, they demonstrate the superiority of the generation task for revealing the explicitness of CC, likely because both the search and the memory task involve overlapping processes (in line with ‘transfer-appropriate processing’).
... Efforts to understand the scope and importance of unconscious mental processes form a prominent part of current research in psychology and cognitive neuroscience, and show no sign of abating despite decades of controversy (e.g., Eriksen, 1960;Hassin, 2013;Hedger, Gray, Garner, & Adams, 2016;Holender, 1986;LeDoux, Michel, & Lau, 2020;Shanks & St. John, 1994). At their heart, many of the disagreements stem from alternative viewpoints about the inferences that can validly be drawn from particular experimental methods and data-analysis techniques. ...
Article
As a method to investigate the scope of unconscious mental processes, researchers frequently obtain concurrent measures of task performance and stimulus awareness across participants. Even though both measures might be significantly greater than zero, the correlation between them might not, encouraging the inference that an unconscious process drives task performance. We highlight the pitfalls of this null-correlation approach and provide a mini-tutorial on ways to avoid them. As reference, we use a recent study by Salvador et al. (2018) reporting a non-significant correlation between the extent to which memory was suppressed by a Think/No-Think cue and an index of cue awareness. In the Null Hypothesis Significance Testing (NHST) framework, it is inappropriate to interpret failure to reject the null hypothesis (i.e., correlation = 0) as evidence for the null. Furthermore, psychological measures are often unreliable, which can dramatically attenuate the size of observed correlations. A Bayesian approach can circumvent both problems and compare the extent to which the data provide evidence for the null versus the alternative hypothesis (i.e., correlation > 0), while considering the usually low reliabilities of the variables. Applied to Salvador et al.'s data, this approach indicates no to moderate support for the claimed unconscious nature of participants' memory-suppression performance—depending on the model of the alternative hypothesis. Hence, more reliable data are needed. When analyzing correlational data, we recommend researchers to employ the Bayesian methods developed here (and made freely available as R scripts), rather than standard NHST methods, to take account of unreliability.
... For relying on introspective report not only restricts the range of subjects available to study, it also requires us to use a very untrustworthy tool in conducting our studies. There is no need to belabor the point: the evidence and arguments showing that we are all too often mistaken or unaware of the processes responsible for our behavior are overwhelming (see, e.g., Shanks & St. John, 1994). ...
... Each of these awareness assessments come with their own limitations. Post-experiment questionnaires have been criticized, as reports of awareness are assessed in different contexts (i.e., verbal reports versus a motor task) and may be held with low selfconfidence (Eriksen, 1960;Nisbett & Wilson, 1977;Shanks & St. John, 1994). Furthermore, the post-experiment questionnaire, drawing task and orientation task rely on memory, as they are completed at the end of reach training, when participants experience small target errors that may go unnoticed. ...
Article
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It is well documented that reaches are adapted when reaching with a visuomotor distortion (i.e., rotated cursor feedback). Less clear is the influence of awareness on visuomotor adaptation, where awareness encompasses knowledge of the changes in one’s reaches and the visuomotor distortion itself. In the current experiment, we asked if awareness governs the magnitude of implicit (i.e., unconscious) visuomotor adaptation achieved, independent of how the distortion is introduced (i.e., abruptly vs. gradually introduced visuomotor distortion), and hence initial errors experienced. Participants were divided into two groups that differed with respect to how the visuomotor distortion was introduced (i.e., Abrupt vs. Gradual Groups) and reached in a virtual environment where a cursor on the screen misrepresented the position of their hand. Participants completed three blocks of 150 reach training trials in the following order: aligned cursor feedback (baseline), rotated cursor feedback (adaptation) and aligned cursor feedback (washout). For the Abrupt Group, the cursor was immediately rotated 45° clockwise (CW) relative to hand motion in the adaptation block, whereas in the Gradual Group, the 45° cursor rotation was gradually introduced over adaptation trials. Following reach training, participants’ awareness of changes in their reaches and the visuomotor distortion were established based on a drawing task, where participants drew the path their hand took to get the cursor on target, as well as a post-experiment questionnaire. Participants were subsequently divided into the following 3 groups: Abrupt-Aware (n = 16), Gradual-Aware (n = 11) and Gradual-Unaware (n = 14). Results revealed that errors differed for the Gradual-Unaware Group at the end of adaptation training compared to the Gradual-Aware Group and at the start of the washout block compared to the Abrupt-Aware Group. Errors in the two aware groups did not differ from each other. These results suggest that awareness may lead to reduced implicit adaptation, regardless of the size of initial errors experienced.
... For instance, the already mentioned neural workspace theory (Dehaene and Naccache, 2001) postulates that, due to its inherent properties, the neurocognitive module that governs automatic unconscious representations cannot be accessed and modified by conscious representations. In contrast, the cognitive models supporting a single memory system or a number of closely integrated systems predict that explicit knowledge may enhance implicit representations in a direct way (e.g., Cleeremans and Jiménez, 2002;Logan, 1988;Shanks and St. John, 1994). In the latter framework, implicit and explicit learning are predicted to unite to boost the formation of integrated knowledge that is both implicit and explicit (see Sanchez and Reber, 2013 for a discussion). ...
Article
The interface issue concerning the nature of interactions between explicit and implicit linguistic knowledge in second language acquisition (SLA) has been a focus of widespread academic interest for almost four decades. However, despite intense debate at the theoretical level and emerging methodologically rigorous studies related to the topic, the issue remains unresolved. With this overview paper, we hope to offer a contribution to the pending theoretical and methodological topics related to the interface in acquiring L2 syntax. First, the paper discusses the definitions and operationalization criteria of implicit and explicit knowledge, as well as their interface. Then, we review the methods and findings of representative studies on domain-general learning and second language acquisition that have explored the interactions between implicit and explicit learning systems. Specifically, we identify the types of interactions that are tenable according to the literature in cognitive psychology and seek evidence for those interactions in the results of published state-of-the-art research. Finally, we compile methodological recommendations for further SLA studies exploring the interface. Following other scholars, throughout the discussion, we argue that bringing the field closer to resolving the interface issue requires an interdisciplinary approach that combines insights and methods from linguistic, psychological and neurocognitive research traditions. Termporary access to the FULL TEXT via a Share Link: https://authors.elsevier.com/a/1eZdQ5YrUxXAh
... Critically, even setting aside the more general issue of whether lack of awareness can be inferred from lack of retrospective memory (see below), the validity of the conclusions regarding unaware EC in the surveillance task hinges on the specificity and sensitivity of the measures used to exclude participants deemed as contingency aware (Lovibond & Shanks, 2002;Newell & Shanks, 2014;Shanks & St. John, 1994). That is, the measure used to establish contingency awareness should (a) identify all participants that were contingency aware as contingency aware and (b) not erroneously identify any participants that were contingency unaware as contingency aware. ...
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Moran et al. (2021) report a multi-lab registered replication of Olson and Fazio’s (2001) surveillance task. The surveillance task is an incidental learning procedure over the course of which participants observe pairings of conditioned stimuli (CSs) and unconditioned stimuli (USs) while engaging in a distracting secondary task. Unaware evaluative conditioning (EC) effects are inferred if participants who fail to report the CS–US contingencies on a post-hoc measure show preference for the CSpos over the CSneg. Moran et al. claimed to establish such effects relying on the criteria used by Olson and Fazio to exclude contingency aware participants from analyses. Here we reexamine Moran et al.’s data using more fine-grained analytic strategies. We show that the contingency awareness measures used by Olson and Fazio and, by extension, Moran et al. lack adequate reliability and validity. Moreover, even assuming valid awareness measures, Bayesian analyses did not provide unambiguous evidence for unaware EC effects under any exclusion criterion and provided decisive evidence against such effects in most models. Finally, a separate analysis that distinguished between fully aware, partially aware, and fully unaware participants shows that evidence for unaware EC is due to the inclusion of partially aware participants in the purportedly unaware subsample. These reanalyses suggest that unaware EC as indexed by the surveillance task has yet to be convincingly demonstrated. We discuss the conceptual, theoretical, and applied implications of these findings with regard to the potential for unaware attitude formation.
... The divergence between the reproduction and recognition tasks in the present experiments might be taken as evidence that the two tasks tap different underlying knowledge representations, one unconscious (often termed "implicit") and the other conscious, declarative, or "explicit" (Batterink et al., 2015)-for a critical review of this dichotomy, see Shanks and St. John (1994). Following Franco et al. (2015), however, a different-though potentially complementary-explanation points rather to the retrieval processes recruited by the two tasks (see also Shanks & Perruchet, 2002). ...
Article
Statistical learning plays an important role in acquiring the structure of cultural communication signals such as speech and music, which are both perceived and reproduced. However, statistical learning is typically investigated through passive exposure to structured signals, followed by offline explicit recognition tasks assessing the degree of learning. Such experimental approaches fail to capture statistical learning as it takes place and require post hoc conscious reflection on what is thought to be an implicit process of knowledge acquisition. To better understand the process of statistical learning in active contexts while addressing these shortcomings, we introduce a novel, processing-based measure of statistical learning based on the position of errors in sequence reproduction. Across five experiments, we employed this new technique to assess statistical learning using artificial pure-tone or environmental-sound languages with controlled statistical properties in passive exposure, active reproduction, and explicit recognition tasks. The new error position measure provided a robust, online indicator of statistical learning during reproduction, with little carryover from prior statistical learning via passive exposure and no correlation with recognition-based estimates of statistical learning. Error position effects extended consistently across auditory domains, including sequences of pure tones and environmental sounds. Whereas recall performance showed significant variability across experiments, and little evidence of being improved by statistical learning, the error position effect was highly consistent for all participant groups, including musicians and nonmusicians. We discuss the implications of these results for understanding psychological mechanisms underlying statistical learning and compare the evidence provided by different experimental measures. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
... Outcome-based measurements of L2 learners' attention such as marking are insufficient to show whether and to what extent L2 learners pay attention to form versus meaning. Innovating the measurement of attention, Leow et al. (2008) and Morgan-Short et al. (2012) adopted think-aloud protocols as an online (real-time) technique to explore these matters; at the same time, think-alouds cannot provide a full account of attentional processes, as learners cannot verbalize every aspect of their attentional behavior (on nonveridicality, see Bowles, 2010;Godfroid, 2020;Rebuschat, 2013;Shanks & St. John, 1994). Think-alouds also have the in-built assumption that processing form and meaning, and the form-meaning relationship, is a conscious process (or else it won't be reflected in the think-aloud protocol). ...
Article
Motivated by a series of interconnected studies on simultaneous attention to form and meaning, we revisit L2 learners' real-time processing of text by using eye-tracking as an unobtrusive method to provide concurrent data on attention allocation. Seventy-five L2 Spanish learners were instructed to attend to an assigned form in a reading passage and to press a button when they noticed it. After reading the passage, the learners answered 10 multiple-choice comprehension questions. The participants' responses to the comprehension questions and their reading behaviors reflected in eye-movement data suggest that attention to grammatical form may hinder L2 learners' simultaneous attention to form and meaning. However, individual differences in global text processing contributed to the differences in the participants' text-comprehension scores over and above the task instruction to attend to form: Slower L2 readers who read the passage more carefully showed better text comprehension.
... In this task, a target stimulus appears at one of four locations on a computer screen across 350 trials and the task was to press a button as fast as possible to indicate each location; the target followed a repeating sequence and the task permits learning of this sequence to be measured. A large literature exists on this form of perceptual-motor learning [44]. ...
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Research on goal priming asks whether the subtle activation of an achievement goal can improve task performance. Studies in this domain employ a range of priming methods, such as surreptitiously displaying a photograph of an athlete winning a race, and a range of dependent variables including measures of creativity and workplace performance. Chen, Latham, Piccolo and Itzchakov (Chen et al. 2021 J. Appl. Psychol. 70 , 216–253) recently undertook a meta-analysis of this research and reported positive overall effects in both laboratory and field studies, with field studies yielding a moderate-to-large effect that was significantly larger than that obtained in laboratory experiments. We highlight a number of issues with Chen et al .'s selection of field studies and then report a new meta-analysis ( k = 13, N = 683) that corrects these. The new meta-analysis reveals suggestive evidence of publication bias and low power in goal priming field studies. We conclude that the available evidence falls short of demonstrating goal priming effects in the workplace, and offer proposals for how future research can provide stronger tests.
... This is in line with previous work suggesting that verbal responses may not reveal all of subjects' knowledge, especially when knowledge is held with low confidence or is retrieved in a different context (Eriksen, 1960;Nisbett & Wilson, 1977;Shanks, Rowland, Rowland, & Ranger, 2005). Conversely, it has been suggested that prediction tasks-such as reporting-during sequence-learning, concept-learning and grammar-learning are based on feelings of familiarity and, therefore, lead to an overestimation of awareness (Cleeremans & Elman, 1993;Shanks & John, 1994). Accordingly, explicit re-aiming as measured by report may be overestimating the actual explicit re-aiming as a result of feelings of familiarity. ...
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Visuomotor rotations are frequently used to study the different processes underlying motor adaptation. Explicit aiming strategies and implicit recalibration are two of these processes. Various methods, which differ in their underlying assumptions, have been used to dissociate the two processes. Direct methods, such as verbal reports, assume explicit knowledge to be verbalizable, where indirect methods, such as the exclusion, assume that explicit knowledge is controllable. The goal of this study was thus to directly compare verbal reporting with exclusion in two different conditions: during consistent reporting and during intermittent reporting. Our results show that our two conditions lead to a dissociation between the measures. In the consistent reporting group, all measures showed similar results. However, in the intermittent reporting group, verbal reporting showed more explicit re‐aiming and less implicit adaptation than exclusion. Curiously, when exclusion was measured again, after the end of learning, the differences were no longer apparent. We suspect this may reflect selective decay in implicit adaptation, as has been reported previously. All told, our results clearly indicate that methods of measurement can affect the amount of explicit re‐aiming and implicit adaptation that is measured. Since it has been previously shown that both explicit re‐aiming and implicit adaptation have multiple components, discrepancies between these different methods may arise because different measures reflect different components.
... It is possible that participants were unaware of the way in which they altered their kinematics during performance and thus underreported their technique changes. Furthermore, it has been argued that the assessment of declarative knowledge via self-report should consist of a qualitative analysis of the information produced by the participants, rather than by a simple Likert scale as used in this study (Shanks & John, 1994). It is also possible that participants did not use many different paddle solutions, but instead chose to alter their technique by leveraging the degrees of freedom made available by the human motor apparatus (Bernstein, 1996). ...
Article
Implicit motor learning paradigms aim to minimize verbal-analytical engagement in motor performance. Some paradigms do this by decreasing working memory activity during practice, which reduces explicit processes associated with the search for motor solutions (e.g., hypothesis testing). Here we designed a mentally demanding motor task to fatigue working memory prior to motor practice and then tested whether it reduced hypothesis testing. Fifty-nine participants were randomly assigned to complete the mentally demanding motor task (cognitive fatigue group) or to complete an undemanding motor task (nonfatigued control group). Feelings of fatigue, working memory functions, electroencephalography (EEG) Fz power, and vagal control were assessed pre- and posttask to quantify the effect of the mentally demanding motor task on cognitive fatigue. Thereafter, an adapted shuffleboard task was completed to determine the impact on hypothesis testing. Hypothesis testing was assessed by self-report, technique changes, and equipment-use solutions. Additionally, verbal-analytical engagement in motor performance was (indirectly) gauged with EEG T7-Fz connectivity and T7 power measures. Participants in the cognitive fatigue group reported more fatigue and displayed moderated working memory functions and Fz theta power. During practice of the shuffleboard task, participants also displayed more technique changes and higher verbal-analytical engagement in motor planning (EEG T7-Fz connectivity), compared with participants in the control group. The mentally demanding motor task suppressed working memory functions, but resulted in more, rather than less, hypothesis testing during shuffleboard practice. The implications are discussed in the context of implicit motor learning theory. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
Article
Evaluative conditioning (EC) refers to a change in liking of a conditioned stimulus (CS) subsequent to its repeated pairing with a valent stimulus (US). Two studies that bring new light on the highly debated question of the role of awareness in EC were conducted. We developed an innovative method motivated by higher order and integration theories of consciousness to distinguish between the role of conscious and unconscious knowledge about the pairings. On each trial of the awareness test, participants had to indicate the valence of the US associated with a given CS and to make a 'structural knowledge attribution' by reporting the basis of their response. Valence identification accuracy was used to evaluate knowledge while the knowledge attribution was used to measure the conscious status of knowledge. Memory attribution indicated conscious knowledge about the pairings while feeling-based and random attributions indicated unconscious knowledge. A meta-analysis of the two studies revealed that valence identification accuracy was above chance level for memory and feeling-based attributions but not for the random attribution. EC was found in the three attributions. While EC effect size was medium for the memory attribution it was small for feeling-based and random attributions. Moreover, Experiment 2 included a delayed test. EC was still present 24 h after the conditioning took place. The results obtained for memory and feeling-based attributions suggest that both conscious and unconscious knowledge may underlie EC. The results obtained for random attribution suggest that EC may also occur without any knowledge of US valence.
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Una vez presentados los resultados previos obtenidos y tras establecer la justificación y los objetivos de la tesis (capítulo 1), se presentan tres capítulos teóricos, donde se realiza un primer acercamiento desde una perspectiva amplia al estudio de las emociones (capítulo 2), pasando por una revisión histórica de los estudios sobre el Condicionami ... ento Evaluativo (capítulo 3) para terminar concretando el campo de estudio del Condicionamiento Evaluativo y presentando las similitudes y diferencias con respecto al Condicionamiento Evaluativo (capítulo 3). Tras este abordaje teórico, se presentan tres capítulos en donde mediante una metodología experimental se explora alguna de las características distintivas entre el Condicionamiento Evaluativo y el Condicionamiento Clásico, así en el primer experimento se explora la influencia del nivel de familiaridad de los estímulos en el nivel de condicionamiento (capítulo 5), en el segundo experimento se analiza la relevancia de la contingencia estadística en el Condicionamiento Evaluativo (capítulos 6), por su parte, en el tercer experimento, se analiza la influencia del tipo de presentación de las parejas EC-El en el nivel de condicionamiento alcanzado (capítulo 7). A continuación se pasa a emplear una metodología de encuesta para comprobar la validez interna de un cuestionario que evalúa el nivel de estabilidad emocional de los participantes (capítulo 8). Por último se realiza un experimento donde se exploran los efectos diferenciales de las presentaciones supra o subliminal de los Els durante la fase de condicionamiento siendo evaluado mediante medidas de tipo cognitivo, conductuales y fisiológicas (capítulo 9)|
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This study investigated the implicit learning of two artificial systems. Two finite-state grammars were implemented with the same tone set (leading to short melodies) and played by the same timbre in exposure and test phases. The grammars were presented in separate exposure phases, and potentially acquired knowledge was tested with two experimental tasks: a grammar categorization task (Experiment 1) and a grammatical error detection task (Experiment 2). Results showed that participants were able to categorize new items as belonging to one or the other grammar (Experiment 1) and detect grammatical errors in new sequences of each grammar (Experiment 2). Our findings suggest the capacity of intra-modal learning of regularities in the auditory modality and based on stimuli that share the same perceptual properties.
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In the IoT and WSN era, large number of connected objects and sensing devices are dedicated to collect, transfer, and generate a huge amount of data for a wide variety of fields and applications. To effectively run these complex networks of connected objects, there are several challenges like topology changes, link failures, memory constraints, interoperability, network congestion, coverage, scalability, network management, security, and privacy to name a few. Thus, to overcome these challenges and exploiting them to support this technological outbreak would be one of the most crucial tasks of modern world. In the recent years, the development of Artificial Intelligence (AI) led to the emergence of Machine Learning (ML) which has become the key enabler to figure out solutions and learning models in an attempt to enhance the QoS parameters of IoT and WSNs. By learning from past experiences, ML techniques aim to resolve issues in the WSN and IoT's fields by building algorithmic models. In this paper, we are going to highlight the most fundamental concepts of ML categories and Algorithms. We start by providing a thorough overview of the WSN and IoT's technologies. We also discuss the vital role of ML techniques in driving up the evolution of these technologies. Then, as the key contribution of this paper, a new taxonomy of ML algorithms is provided. We also summarize the major applications and research challenges that leveraged ML techniques in the WSN and IoT. Eventually, we analyze the critical issues and list some future research directions.
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A persistent metaphor in decision-making research casts people as intuitive statisticians. Popular explanations based on this metaphor assume that the way in which people represent the environment is specified and fixed a priori. A major flaw in this account is that it is not clear how people know what aspects of an environment are important, how to interpret those aspects, and how to make decisions based on them. We suggest a theoretical reorientation away from assuming people’s representations towards a focus on explaining how people themselves specify what is important to represent. This perspective casts decision makers as intuitive scientists able to flexibly construct, modify, and replace the representations of the decision problems they face.
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In recent years artificial neural networks achieved performance close to or better than humans in several domains: tasks that were previously human prerogatives, such as language processing, have witnessed remarkable improvements in state of the art models. One advantage of this technological boost is to facilitate comparison between different neural networks and human performance, in order to deepen our understanding of human cognition. Here, we investigate which neural network architecture (feedforward vs. recurrent) matches human behavior in artificial grammar learning, a crucial aspect of language acquisition. Prior experimental studies proved that artificial grammars can be learnt by human subjects after little exposure and often without explicit knowledge of the underlying rules. We tested four grammars with different complexity levels both in humans and in feedforward and recurrent networks. Our results show that both architectures can “learn” (via error back-propagation) the grammars after the same number of training sequences as humans do, but recurrent networks perform closer to humans than feedforward ones, irrespective of the grammar complexity level. Moreover, similar to visual processing, in which feedforward and recurrent architectures have been related to unconscious and conscious processes, the difference in performance between architectures over ten regular grammars shows that simpler and more explicit grammars are better learnt by recurrent architectures, supporting the hypothesis that explicit learning is best modeled by recurrent networks, whereas feedforward networks supposedly capture the dynamics involved in implicit learning.
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In der deutschen Literatur wird das Thema Intuition noch nicht differenziert in seinen wichtigen Facetten betrachtet. Bislang wird Intuition vornehmlich auf Basis der Arbeiten von Prof. Gigerenzer, als Erfahrungsintuition bzw. heuristische Entscheidungen auf Basis sog. Daumenregeln beschrieben. Amerikanische Forschungsarbeiten werden bislang weniger berücksichtigt. Häufig wird unter Intuition das sog., unbegründete Bauchgefühl untersucht (Prof. Klein). Diese Arbeiten gehen sogar soweit, dass antitipatorische Entscheidungen einbezogen werden (Dr. Radin). Daher soll in dieser Studie die Intuition dreigeteilt untersucht werden, um auch die wirklich unbewussten, intuitiven Entscheidungen einzubeziehen. Dieser Ansatz ist besonders innovativ, weil zum Thema Intuition bisher nur Studien auf Basis von Einzeltheorien im Vergleich zur Rationalität vorliegen. In diesem Forschungsprojekt sollen vier wichtige, unterschiedliche Entscheidungsgrundlagen (RHIBA) erstmals zusammenhängend im Vergleich erforscht werden: (R) Rationale, kognitive Entscheidungsfindung, (H) Heuristische Entscheidungen („Faustregeln“), (I) Intuitive Entscheidungen bzw. das sog. Bauchgefühl oder (P) die unbegründete Entscheidung (A) Antizipation) RHIA. Das Fehlen einer solchen zusammenhängenden Untersuchung mag in der Komplexität des Versuchsaufbaus liegen. Für die Forschung und insbesondere die Entwicklung von Anwendungsfeldern wäre das Gelingen eines solchen Prototypens von entscheidender Bedeutung.
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Sequence learning in serial reaction time tasks (SRTT) is an established, lab-based experimental paradigm to study acquisition and transfer of skill based on the detection of predictable stimulus and motor response sequences. Sequence learning has been mainly studied in key presses using visual target stimuli and is demonstrated by better performance in predictable sequences than in random sequences. In this study, we investigated sequence learning in the context of more complex locomotor responses. To this end, we developed a novel goal-directed stepping SRTT with auditory target stimuli in order to subsequently assess the effect of aging on sequence learning in this task, expecting that age-related performance reductions in postural control might disturb the acquisition of the sequence. We used pressure-sensitive floor mats to characterise performance across ten blocks of trials. In Experiment 1, 22 young adults demonstrated successful acquisition of the sequence in terms of the time to step on the target mat and percent error and thus validated our new paradigm. In Experiment 2, in order to contrast performance improvements in the stepping SRTT between 27 young and 22 old adults, motion capture of the feet was combined with the floor mat system to delineate individual movement phases during stepping onto a target mat. The latencies of several postural events as well as other movement parameters of a step were assessed. We observed significant learning effects in the latency of step initiation, the time to step on the target mat, and motion parameters such as stepping amplitude and peak stepping velocity, as well as in percent error. The data showed general age-related slowing but no significant performance differences in procedural locomotor sequence learning between young and old adults. The older adults also had comparable conscious representations of the sequence of stimuli as the young adults. We conclude that sequence learning occurred in this locomotor learning task that is much more complex than typical finger-tapping sequence learning tasks, and that healthy older adults showed similar learning effects compared to young adults, suggesting intact locomotor sequence learning capabilities despite general slowing and normal age-related decline in sensorimotor function.
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Measurement of consciousness is one of the key methodological problems of cognitive experiments. The choice of method is often made without reference to a specific theory or the explication of the underlying assumptions about the nature of the phenomenon being measured. It is suggested that the lack of theoretical justification of the employed methods leads to unconstructive criticism and disagreement among researchers. We discussed the most common awareness measures in research on learning, memory, perception, and the underlying assumptions about the nature of consciousness and their relationship to theories of consciousness. The degree of theoretical justification of consciousness measures was assessed in a sample of 179 experimental articles. It was shown that in only a quarter of cases, the researchers linked the methods with corresponding assumptions about the nature of consciousness. In the rest of the cases, the choice of method was not theoretically justified.
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Studies on unconscious mental processes typically require that participants are unaware of some information (e.g., a visual stimulus). An important methodological question in this field of research is how to deal with data from participants who become aware of the critical stimulus according to some measure of awareness. While it has previously been argued that the post hoc selection of participants dependent on an awareness measure may often result in regression-to-the-mean artifacts (Shanks, 2017), a recent article ( Sklar et al., 2021 ) challenged this conclusion claiming that the consideration of this statistical artifact might lead to unjustified rejections of true unconscious influences. In this reply, we explain this pervasive statistical problem with a basic and concrete example, show that Sklar et al. fundamentally mischaracterize it, and then refute the argument that the influence of the artifact has previously been overestimated. We conclude that, without safeguards, the method of post hoc data selection should never be employed in studies on unconscious processing.
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Animal studies using selective serotonin reuptake inhibitors (SSRIs) and learning paradigms demonstrated that serotonin is important for flexibility in executive functions and learning. SSRIs might facilitate relearning through neuroplastic processes and thus exert their clinical effects in psychiatric diseases where cognitive functioning is affected. However, translation of these mechanisms to humans is missing. In this randomized placebo-controlled trial, we assessed functional brain activation during learning and memory retrieval in healthy volunteers performing associative learning tasks aiming to translate facilitated relearning by SSRIs. To this extent, seventy-six participants underwent three MRI scanning sessions: (1) at baseline, (2) after three weeks of daily associative learning and subsequent retrieval (face-matching or Chinese character–noun matching) and (3) after three weeks of relearning under escitalopram (10mg/day) or placebo. Associative learning and retrieval tasks were performed during each fMRI session. Statistical modelling was done using a repeated-measures ANOVA, to test for content-by-treatment-by-time interaction effects. During the learning task, a significant substance-by-time interaction was found in the right insula showing a greater deactivation in the SSRI cohort after 21 days of relearning compared to the learning phase. In the retrieval task, there was a significant content-by-time interaction in the left angular gyrus (AG) with an increased activation in face-matching compared to Chinese-character matching for both learning and relearning phases. A further substance-by-time interaction was found in task performance after 21 days of relearning, indicating a greater decrease of performance in the placebo group. Our findings that escitalopram modulate insula activation demonstrates successful translation of relearning as a mechanism of SSRIs in human. Furthermore, we show that the left AG is an active component of correct memory retrieval, which coincides with previous literature. We extend the function of this region by demonstrating its activation is not only stimulus dependent but also time constrained. Finally, we were able to show that escitalopram aids in relearning, irrespective of content.
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50 days' free access to ours article. Anyone clicking on this link before June 12, 2021 will be taken directly to the final version of this article on ScienceDirect, which they are welcome to read or download. No sign up, registration or fees are required. https://authors.elsevier.com/a/1cyTMcBxf2h7h #---------------------------------------------------------##---------------------------------------------## Although the practice schedule and variation in incidental context have be en investigated together, it is not clear wh ether just variation in incidental context can be neficiate motor learning. Therefore, the present stud y aime d to investigate the effect of context variability on motor learning. We hypothesized the practice in a variable incidental context would enable learners to be more resistant to the effects of the contextual ch anges wh en compared to a constant incidental context practice. Twenty-four participants were assigned to one of the two groups: constant incidental context (G_CC) or variable incidental context (G_VC). During practice, the G_CC practiced a sequence keypressing task in one color and a position showed on the compu ter screen. The G_VC practiced the same sequence in four different combinations of color and position. Twenty four hours, the same contexts practiced on practice (SAM E) was perform ed and imme diately after, a new sequential moveme nt in new color and new position (SWITCH) was perform ed. The results indicated that the G_VC showed be tter performa nc e than the G_CC on the SWITCH condition, ma inly in me asures related to planning/selection process. The results were explained by degree of similarity am ong processing events engaged du ring different mome nts and by developme nt of a filter of informa tion based on attentional selection.
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The Process Dissociation Procedure (PDP) and Verbal Report Framework (VRF) reveal that both explicit (conscious) and implicit (unconscious) processes contribute to visuomotor adaptation. We looked to determine whether these two assessment methods establish similar processes underlying visuomotor adaptation by comparing the magnitude of explicit and implicit adaptation over time between the two assessments and to post-experiment assessments of awareness of the visuomotor distortion. Three groups of participants (PDP, VRF, VRF No-Cursor) completed three blocks of reach training in a virtual environment with a cursor rotated 40° clockwise relative to hand motion. Explicit and implicit adaptations were assessed immediately following each block, and again 5 min later. The VRF No-Cursor group completed the same assessment trials as the VRF group, but no visual feedback was presented during explicit and implicit assessment. Finally, participants completed a post-experiment questionnaire and a drawing task to assess their awareness of the visuomotor rotation and changes in reaches at the end of the experiment, respectively. We found that all groups adapted their reaches to the rotation. Averaged across participants, the magnitude and retention of explicit and implicit adaptations were similar between the PDP group and VRF group, with the VRF group demonstrating greater implicit adaptation than the VRF No-Cursor group. Furthermore, the magnitude of explicit adaptation established in the VRF group was not related to participant’s post-experiment awareness of the visuomotor distortion nor how they had changed their reaches, as observed in the PDP group and VRF No-Cursor group. Together, these results indicate that, explicit adaptation established via typical VRF methods does not reflect one’s awareness of the visuomotor distortion at the end of the experiment, and hence the established processes underlying visuomotor adaptation are dependent on method of assessment (i.e., PDP versus VRF).
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The article addresses the problem of unconscious gaining of abstract knowledge. Participants solved circular 5-letter anagram arranged by the same invariant scheme. The learned schematic invariant is not perceptive, contrary to the usual invariant acquisition technique in other studies. The possibility of implicit learning of a solution scheme is discussed. Efficiency of anagram solving is compared between the groups with constant or changed solution scheme during the test stage. The change of the solution scheme leads to a decrease of efficiency, i.e. to the lower number of the solved anagrams. The results support the possibility of gaining unconscious abstract knowledge concerning the scheme without any perceptual invariant component. Possible use of a similar stimulus material in studies of interaction between visual and verbal components of working memory is briefly discussed.
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The demonstration that unconscious learning supports instrumental behaviors (i.e., choosing the stimuli that lead to rewards) is central for the tenet that unconscious cognition sustains human adaptation. Recent studies, using reliable subliminal conditioning paradigms, have found evidence against unconscious knowledge sustaining accurate instrumental responses. The present preregistered study proposes an alternative paradigm, in which unconscious processing is stimulated not by subliminally exposing the predictive (conditioned) stimuli, but by employing predictive regularities that are complex and difficult to detect consciously. Participants (N = 211) were exposed to letter strings that, unknown to them, were built from two complex artificial grammars: a “rewarded’’ or a “non-rewarded” grammar. On each trial, participants memorized a string, and subsequently had to discriminate the memorized string from a distractor. Correct discriminations were rewarded only when the identified string followed the rewarded grammar, but not when it followed the non-rewarded grammar. In a subsequent test phase, participants were presented with new strings from the rewarded and from the unrewarded grammar. Their task was now to directly choose the strings from the rewarded grammar, in order to collect more rewards. A trial-by-trial awareness measure revealed that participants accurately choose novel strings from the rewarded grammar when they had no conscious knowledge of the grammar. The awareness measure also showed that participants were accurate only when the unconsciously learned grammar led to conscious judgments. The present study provides an alternative to subliminal conditioning paradigms and shows that unconscious knowledge can guide instrumental responses.
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People can behave in a biased manner without being aware that their behavior is biased, an idea commonly referred to as implicit bias. Research on implicit bias has been heavily influenced by implicit measures, in that implicit bias is often equated with bias on implicit measures. Drawing on a definition of implicit bias as an unconscious effect of social category cues on behavioral responses, the current article argues that the widespread equation of implicit bias and bias on implicit measures is problematic on conceptual and empirical grounds. A clear separation of the two constructs will: (1) resolve ambiguities arising from the multiple meanings implied by current terminological conventions; (2) stimulate new research by uncovering important questions that have been largely ignored; (3) provide a better foundation for theories of implicit bias through greater conceptual precision; and (4) highlight the broader significance of implicit bias in a manner that is not directly evident from bias on implicit measures.
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Abstract Research examining the relation between explicit and implicit forms of memory has generated a great deal of evidence concerning the issue of multiple memory systems. This article focuses on an extensively studied implicit memory phenomenon, known as direct or repetition priming, and examines the hypothesis that priming effects on various tasks reflect the operation of a perceptual representation system (PRS)-a class of cortically based subsystems that operate at a presemantic level and support non conscious expressions of memory. Three PRS subsystems are examined: visual word form, structural description, and auditory word form. Pertinent cognitive, neuropsychological, and neurobiological evidence is reviewed, alternative classificatory schemes are discussed, and important conceptual and terminological issues are considered.
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College students' presses on a telegraph key were occasionally reinforced by light onsets in the presence of which button presses (consummatory responses) produced points later exchangeable for money. One student's key presses were reinforced according to a variable-ratio schedule; key presses of another student in a separate room were reinforced according to a variable-interval schedule yoked to the interreinforcement intervals produced by the first student. Instructions described the operation of the reinforcement button, but did not mention the telegraph key; instead, key pressing was established by shaping. Performances were comparable to those of infrahuman organisms: variable-ratio key-pressing rates were higher than yoked variable-interval rates. With some yoked pairs, schedule effects occurred so rapidly that rate reversals produced by schedule reversals were demonstrable within one session. But sensitivity to these contingencies was not reliably obtained with other pairs for whom an experimenter demonstrated key pressing or for whom the reinforcer included automatic point deliveries instead of points produced by button presses. A second experiment with uninstructed responding demonstrated sensitivity to fixed-interval contingencies. These findings clarify prior failures to demonstrate human sensitivity to schedule contingencies: human responding is maximally sensitive to these contingencies when instructions are minimized and the reinforcer requires a consummatory response.
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The criteria by which incidentally acquired knowledge of an artificial grammar (A. S. Reber, 1967) could be unconscious was explored in 5 experiments. Participants trained on an artificial grammar lacked metaknowledge of their knowledge: Participants classified substantially above chance even when they believed that they were literally guessing, and, under some conditions, participants' confidence in incorrect decisions was just as great as their confidence in correct decisions. However, participants had a large degree of strategic control over their knowledge: Participants trained on 2 grammars could decide which grammar to apply in a test phase, and there was no detectable tendency for participants to apply the other grammar. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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Our experiments asked whether implicit learning occurs for novel nonverbal associations. We presented subjects with color names printed in incongruent colors; subjects were asked to name the color in which the word was printed. In Experiment 1, each of 7 color words were associated with the same incongruent color across 6 blocks of trials, and then the color-word associations were abruptly changed. Both control subjects and patients with amnesia reduced their color-naming times across the first 6 trial blocks, and naming times increased when the color-word associations were changed. In Experiment 2, similar results were obtained when neutral words were associated with colors. In Experiment 3, we found that naming times were not disrupted when an irrelevant dimension (typecase) was changed. Finally, in Experiment 4, we found that the effect persisted across a 5-min delay. These studies provide evidence that implicit learning occurs for nonverbal associations and is independent of the brain structures damaged in amnesia.
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Language depends on a normally functioning left hemisphere. This central fact of human cerebral dominance was well established by 19th century aphasiologists and has been repeatedly confirmed by subsequent investiga­ tions. Predominance, however, does not imply exclusivity. As demonstrated by the commissurotomy patients studied by Eran Zaidel and associates, the right hemisphere is also capable of subserving some linguistic functions. The question, then, is not whether the right hemisphere can process language, but how and when it does so. This volume focuses on the right hemisphere's contribution to one important aspect oflanguage, lexical semantics. Although the right hemisphere may well be involved in other linguistic functions, such as prosody, the greatest evidence for right hemisphere language competence has been obtained for the processing of word meanings. In addition, cognitive psychology and psycho­ linguistics have provided us with well-developed models of the lexicon and lexical access to guide our inquiry. Finally, there are techniques available for studying lateralized lexical processing in the normal as well as in the brain­ injured hemispheres. For these reasons, a focus on the lexicon is likely to yield the greatest number of insights about right-hemisphere language processing.
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30 students rated the relative grammaticality of isolated sentences twice, with sentences presented repeatedly between the two judgments. Subjects were asked to adopt either a differentiation or an enrichment strategy during a repetition phase. The former strategy involved differentiation by structurally analyzing the sentences, while the latter involved enrichment by supplying situational contexts for the sentences. Analysis showed an interaction between a strategy adopted and the time of judgments such that the subjects instructed to adopt a differentiation strategy tended to use a more stringent criterion on judgments after than before repetition, whereas the subjects asked to adopt an enrichment strategy showed a slight tendency to use a more lenient criterion. These findings indicated that these two types of mental processes are involved in part in the change in criterion for judgments of grammaticality as shown in previous studies.
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Comparisons of the relative sensitivity of direct and indirect tasks can provide definitive evidence for unconscious memory when the direct and indirect tasks are matched on all characteristics except instructions. To demonstrate unconscious memory in normal adults, subjects first viewed pairs of words and named one cued word in each pair. During the subsequent assessment of memory, new words and either previously cued words (Experiment 1) or previously uncued words (Experiments 2A and 2B) were presented against a background mask. The subjects judged whether a word was old or new (direct task) or whether the contrast between a word and the mask was high or low (indirect task). For cued words, the direct task was more sensitive than the indirect task. However, for uncued words, the indirect task was initially more sensitive than the direct task, even though the direct task exhibited hypermnesia so that it became more sensitive than the indirect task across trial blocks. The greater initial sensitivity of the indirect task implicates unconscious processes underlying memory for the uncued words. These results indicate that unconscious processes in normal adults can be revealed through comparisons of comparable direct and indirect measures.
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The authors propose a rule-plus-exception model (RULEX) of classification learning. According to RULEX, people learn to classify objects by forming simple logical rules and remembering occasional exceptions to those rules. Because the learning process in RULEX is stochastic. the model predicts that individual Ss will vary greatly in the particular rules that are formed and the exceptions that are stored. Averaged classification data are presumed to represent mixtures of these highly idiosyncratic rules and exceptions. RULEX accounts for numerous fundamental classification phenomena, including prototype and specific exemplar effects, sensitivity to correlational information, difficulty of learning linearly separable versus nonlinearly separable categories, selective attention effects, and difficulty of learning concepts with rules of differing complexity. RULEX also predicts distributions of generalization patterns observed at the individual subject level.
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Both the specific similarity of test items to study items and the grammaticality of test items were found to be major determinants of performance under task conditions common in the literature. Results bearing on the issue of how item-specific effects are coordinated with knowledge pooled across items are: (a) Better item memory resulted in smaller rather than larger effects of specific similarity on judgments of grammaticality, suggesting that items can be too well differentiated to support transfer to new items. (b) Variation in the effect of specific similarity did not result in compensatory variation in grammaticality, suggesting that any scheme that tightly links the effects of the two variables is insufficient. (c) Differential reliance on the 2 knowledge resources was not under good instructional control, which poses a problem for accounts that use functional task analyses to coordinate functionally different memories.
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Feelings of familiarity are not direct products of memory. Although prior experience of a stimulus can produce a feeling of familiarity, that feeling can also be aroused in the absence of prior experience if perceptual processing of the stimulus is fluent (e.g., Whittlesea, Jacoby, & Girard, 1990). This suggests that feelings of familiarity arise through an unconscious inference about the source of processing fluency. The present experiments extend that conclusion. First, they show that a wide variety of feelings about the past are controlled by a fluency heuristic, including feelings about the meaning, pleasantness, duration, and recency of past events. Second, they demonstrate that the attribution process does not rely only on perceptual fluency, but can be influenced even more by the fluency of conceptual processing. Third, they show that although the fluency heuristic itself is simple, people's use of it is highly sophisticated and makes them robustly sensitive to the actual historical status of current events.
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It is often assumed that there is more than one kind of learning-or more than one memory system-each of which is specialized for a different function. Yet, the criteria by which the varieties of learning and memory should be distinguished are seldom clear. Learning and memory phenomena can differ from one another across species or situations (and thus be specialized) in a number of different ways. What is needed is a consistent theoretical approach to the whole range of learning phenomena, and one is explored here. Parallels and contrasts in the study of sensory systems illustrate one way to integrate the study of general mechanisms with an appreciation of species-specific adaptations.
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'Summary.-11 field-dependent and 14 field-independent students rated the relative grarnmaticality of sentences three times, with sentences presented repeatedly during the first and second judgments. AU the subjects received negative reinforcement after the second judgments. Analyses showed that field-independent subjects tended to adopt a more stringent criterion on judgments after than before repetition, whereas no change in criterion was found for field-dependent subjects. Negative reinforcement showed only a tendency to lead field-dependent subjects toward greater change to a more lenient criterion than field-independent subjects. Change in judgments of grammaticality are reliably associated with the cognitive style of subjects, field dependence or field independence. Previous studies have shown that the mental state of subjects influences linguistic intuition in judging grammaticality of sentences (Nagata, 1988, 1989b, 1989~). For example, Nagata (1988) found that a judgment criterion for isolated sentences became more stringent after than before a repetition treatment. This finding was interpreted as suggesting that during repetition subjects had been engaged more in differentiac~n~ than in enriching the syntactic and/or semantic properties of the sentences. Subsequent studies support ths view (Nagata, 1987a, 1987b, 1989b, 1989~). In this study field dependence-independence is examined as a possible variable influencing judgments of grammaticality. Previous evidence suggests that field-independent people with developed cognitive restructuring skills show an impersonal orientation, while field-dependent people with less cognitive structuring skills show developed interpersonal competencies (Witkin & Goodenough, 1977, 1981; Witlun, Goodenough, & Oltman, 1979). For example, studies using an incidental learning paradigm have indicated that field-dependent people have better recall of social words than fieldindependent people (Fitzgibbons, Goldberger, & Eagle, 1965; Eagle, Goldberger, & Breitman, 1969; Fitzgibbons & Goldberger, 1971; Ruble & Nakamura, 1972). Goldberger and Bendich (1972) noted that fielddependent subjects incorporate more social words in free association from previously given incidental words. It is quite plausible then that fielddependent and field-independent people may adopt differing cognitive strategies when judging the grammaticality of sentences. Specifically, since fielddependent people are likely to be more sensitive to social cues in the 'Dee gratitude is due Professor S. Oba €or his advice in carrying out this study and D. D. stein%erg for his reading of an earlier version of this paper. 'School of Health Sciences, Shikata, Okayama 700, Japan.
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Psychologists are invited to discuss whether "consciousness is what psychologists actually examine." In making the latter claim, Anthony J. Marcel (1988) does not mean that consciousness is all of what psychologists actually examine. But Marcel's giving this reason for discussion in the way that he does implies clearly that consciousness is a substantial part of what psychologists have been examining all along. By consciousness, Marcel means phenomenal experience and includes reports based on direct acquaintance with phenomenal experience (though such reports are usually objects of secondary, methodological interest). In support of Marcel's thesis, I argue that the very common reports that psychologists collect in studies of perception, and so on, actually report phenomenal experiences of particular kinds. For example, how can you know and report what you are now perceiving unless you have direct acquaintance with the phenomenal experiences that are now involved in your perceiving what you are perceiving? Also, I argue that Gibson's (1979) account for the visual guidance of locomotion (an account that one might well expect to be free of reference to phenomenal experience) is driven back, for strong theoretical reasons, to direct acquaintance with phenomenal experience. If Gibson's account is correct, then much more behavior than reporting behavior depends on acquaintance with phenomenal experience. I also discuss the claim that one can visually guide one's behavior by means of a nonconscious process that selects what to do based on nonconscious visual representations.
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The author reviews two current conflicting theories of what a picture is: (1) that it consists of a sheaf of light rays coming to a station point or perceiver, each corresponding to a spot of color on the picture surface and hence that the picture can stand for a real object or scene insofar as the rays from the picture are the same as the rays from the real object; (2) that it consists of a set of symbols, more or less like words, and the perceiver must learn to 'read' it. According to the first theory, a child can perceive an object in a picture as soon as it can perceive a real object; according to the second one, the child must learn to 'read' the picture much as it learns to read written speech. He points out the fallacies of both theories, shows that they cannot be combined and suggests a new theory based on the radical assumption that light can convey information about the world and, hence, that the phenomenal world does not have to be constructed by the mind (or the brain) out of meaningless data. This theory makes it possible to distinguish between the pictorially mediated perception of the features of a world and the direct perception of the features of the surroundings and yet to understand that there is common information for the features they have in common. His theory accounts for the difference between verbal and visual thinking. Visual thinking is freer and less stereotyped than verbal thinking; there is no vocabulary of picturing as there is of saying. As every artist knows, there are thoughts that can be visualized without being verbalized. /// L'auteur passe en revue deux théories courantes et opposées sur la nature de l'image: (1) l'image est formée d'un faisceau de rayons lumineux convergeant vers un point précis: le spectateur; chaque rayon correspond à une tache de couleur sur la surface de l'image et par conséquent celle-ci peut être considérée comme un objet réel ou une scène dans la mesure où les rayons provenant de l'image sont semblables aux rayons provenant de l'objet réel; (2) l'image est formée par un ensemble de symboles qui sont à peu près comme les mots et le spectateur doit apprendre à la 'lire'. Selon la première théorie, un enfant peut percevoir un objet dans une image dès qu'il peut percevoir l'objet réel; selon la seconde, l'enfant doit apprendre à 'lire' l'image de la même façon qu'il doit apprendre à lire le discours écrit. Il met en évidence ce qu'il y a de faux dans ces deux théories, montre qu'elles ne peuvent se combiner et suggère une nouvelle théorie basée sur l'hypothèse hardie que la lumière peut véhiculer de l'information et que par conséquent l'esprit (ou le cerveau) n'a pas besoin de construire le monde des apparences à partir de données dépourvues de signification. Cette théorie rend possible la distinction entre la perception du monde médiatisée par l'image et la perception directe de ce qui nous entoure tout en nous permettant de comprendre qu'une information semblable rende compte de leurs particularités communes. Cette théorie précise la différence entre la pensée verbale et la pensée en images. La pensée en images est plus libre et moins stéréotypée que la pensée verbale; il n'y a pas de vocabulaire de l'image comme il y a un vocabulaire de la parole. Les artistes savent bien qu'il y a des pensées qu'on peut imaginer sans les formuler.
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The tremendous advances in electronic data processing are likely to result in revolutionary changes in the theories and practices of taxonomy. The process of classification is being removed from speculations regarding the origin of the taxa being classified. A natural classification is one whose taxa share the largest number of properties and which is most useful for a wide range of purposes. The principles of numerical taxonomy are stated briefly and illustrated by means of diagrammatic examples. The relative roles of the taxonomist and computer are discussed and estimates given of computer time and costs involved in numerical taxonomic work. The numerical taxonomic work done in botany so far is discussed and the paper concludes with a brief mention of several problems of numerical taxonomy with regard to botanical work. These are: scarcity of characters, correlations between cytogenetic work and phenetic similarities, and problems raised by hybridization.
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Paired associates were presented to 25 surgical patients following the induction of anesthesia by thiopental, vecuronium, and isoflurane. Postoperative testing (immediately or after two weeks) showed no free recall for the list; nor was there significant cued recall or recognition, compared to a matched control list. However, a free-association task showed a significant priming effect on both immediate and delayed trials. At least under some conditions, adequate surgical anesthesia appears to abolish explicit, but not implicit, memory for intraoperative events.
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Classical conditioning experiments are reviewed in which the dependent variables are subjective responses, typically involving the evaluation of stimulus materials. These experiments suggest that classical conditioning produces a positive or negative change in the evaluation of previously neutral stimuli. We re-interpret these studies as well as presenting data of our own to support the view that apparently disparate conditioning techniques have an underlying common mechanism — the elicitation and transfer of an evaluative response.We postulate that a subjective evaluative response, rather than implicit or explicit behaviour acts, carries the mechanism of conditioning. This leaves free the actual repertoire of responses (adaptive or maladaptive) in which the subject engages, and also suggests a way through the complex problem of how behaviour can be generalized outside clinical and laboratory situations. Subjective evauations are differentiated from states of pleasure (and hence from hedonism), attitude, emotions and approach—avoidance behaviour.The experiments reviewed are selected from the verbal, attitude and evaluative response conditioning literature, and they are used to shift attention from a model of classical conditioning in which the emphasis is on a specific motor or autonomic response as “the” UCR to one which substitutes a process of unmediated appraisal which we have called the evaluative response. The relevance of this formulation to behaviour theory and to behaviour therapy is discussed in relation to cognitively oriented models.
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Abstract Some important empirical findings and theoretical positions that interest contemporary students of learning and memory are discussed in the context of Luria's (1979) memory coherence perspective. This approach assumes that an important challenge to memory function is remaining closed to the influence of associations that are extraneous to the demands of the task at hand. We argue that the ability to support configural associations between representations of the joint occurrence or conjunction of two or more stimulus elements and a target memory is an important feature of a closed system but that an open system can support only elemental associations with the target. Successful performance in many tasks used to study memory can be achieved by elemental associations, but other tasks require the formation of and retrieval by configural associations. From this perspective, the pattern of spared and impaired performance often seen in animals and people with brain damage to the hippocampal system or in amnesic people of various etiologies results because their memory systems are open and can support only elemental associations.
An evaluation of exemplar-based models of generalization was provided for ill-defined categories in a category abstraction paradigm. 72 undergraduates initially classified 35 high-level distortions into 3 categories, defined by 5, 10, and 20 different patterns, followed by a transfer test administered immediately and after 1 wk. The transfer patterns included old, new, prototype, and unrelated exemplars of which the new patterns were at 1 of 5 levels of similarity to a particular training (old) stimulus. In both experiments, increases in category size and old–new similarity facilitated transfer performance. However, the effectiveness of old–new similarity was strongly attenuated by increases in category size and delay of the transfer test. It is concluded that examplar-based generalization may be effective only under conditions of minimal category experience and immediacy of test; with continued category experience, performance on the prototype determines classification accuracy. (22 ref)
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The present experiment investigated effects of reinforcer value on sensitivity to operant force contingencies in humans. Subjects were exposed to non-salient, non-verbal operant contingencies with feedback stimuli of either low or high motivational value. Subjects who received feedback stimuli with back-up reinforcers of high motivational value demonstrated reliable adjustment to the arranged force contingencies, whereas force changes in subjects receiving low motivational feedback stimuli were unreliable. In accordance with standard animal findings, these results indicate that reinforcer value may affect operant conditioning in humans, but its effects are hypothesized to be confined to conditioning that is not mediated verbally.
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Four experiments in which subjects learned to control two versions of a complex simulated process control task show that verbalizable knowledge of procedures used to perform these tasks is very limited and is acquired late in learning. Individual learning curves associated with these tasks showed sudden improvements in performance, which were not accompanied by a similar increase in verbalizable knowledge. It was also found that verbal instructions consisting of exemplar memorization, strategies for rule induction, simple heuristics, and experts' instructions were all effective in enhancing novice subjects' performance. A theoretical framework is proposed in which subjects draw on two separate but interacting knowledge structures to perform these tasks. One knowledge structure is based on memory for past experiences (close analogies), and the other is based on one's current mental model of the task. Implicit sets of competing rules that control response selection are derived from both sources of knowledge. It is suggested that dissociations between task performance and verbalizing occur because memory-based processing tends to have more control over response selection because of its greater specificity, whereas a mental model tends to be the preferred mode for verbal reporting because of its greater accessibility.
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Three experiments examine the effects of two different forms of explanation on assisted performance on a complex search task. The task involves determining which of a set of factories is responsible for polluting a river by testing the river for the presence or absence of various pollutants. All subjects receive computer suggestions as to which pollutants they should test for. In addition, some subjects receive an explanation of the principle according to which the advice program works. Two forms of explanation are compared. Experiment 1 shows that subjects who are allowed to ask “why” each computer recommendation is made perform significantly better than those who are provided with a block text of explanation at the start of each trial. Experiment 2 shows that the latter type of explanation is not completely ineffective, however. Subjects who are required to verbalize following the single explanation perform significantly better than do subjects who are required to verbalize but who have not received any form of explanation. Finally, Experiment 3 shows that subjects who receive the multiple “why” explanations or the explanation/verbalization combination maintain a superior performance level on subsequent unaided trials.
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Three experiments explore the relationship between performance on a cognitive task and the explicit or reportable knowledge associated with that performance (assessed here by written post-task questionnaire). They examine how this relationship is affected by task experience, verbal instruction and concurrent verbalization. It is shown that practice significantly improves ability to control semi-complex computer-implemented systems but has no effect on the ability to answer related questions. In contrast, verbal instruction significantly improves ability to answer questions but has no effect on control performance. Verbal instruction combined with concurrent verbalization does lead to a significant improvement in control scores. Verbalization alone, however, has no effect on task performance or question answering.
Article
Recent attempts to teach apes rudimentary grammatical skills have produced negative results. The basic obstacle appears to be at the level of the individual symbol which, for apes, functions only as a demand. Evidence is lacking that apes can use symbols as names, that is, as a means of simply transmitting information. Even though non-human animals lack linguistic competence, much evidence has recently accumulated that a variety of animals can represent particular features of their environment. What then is the non-verbal nature of animal representations? This question will be discussed with reference to the following findings of studies of serial learning by pigeons. While learning to produce a particular sequence of four elements (colours), pigeons also acquire knowledge about the relation between non-adjacent elements and about the ordinal position of a particular element. Learning to produce a particular sequence also facilitates the discrimination of that sequence from other sequences.
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When memory is required, sentence reading time patterns are U-shaped over the phrases, with prolonged pauses at phrase boundaries. Qualitative hypotheses suggest why subjects engage in higher-level coding at phrase boundaries. Quantitative models account for how long subjects pause there. A two-process additive model accounts well for the data and better than nine other models. Beyond a base reading and motor time, the model includes an organization process for words in the current phrase and a contextual integration process for all preceding words in the sentence. This model is similar to serial processing models previously proposed for coding word lists, and an analysis of past research reveals coding similarities for sentences and word lists when memory demands are high.
Article
The process dissociation procedure (PDP) was introduced as a general-purpose tool for quantifying the extent to which performance on various cognitive tasks is mediated by consciously controlled versus automatic processes. In this paper, we consider several aspects that limit the procedure's domain of application. We suggest that the PDP is inappropriate for studying performance of implicit versus explicit memory tests because its focus on conscious versus automatic processes is different from the distinction between intentional versus non-intentional remembering that is targeted by implicit and explicit memory tests. We point out that the complexity of the instructions that are required for the procedure makes it unsuitable for use with special populations, such as amnesic patients. An examination of two core assumptions of the procedure (invariance of recollection and invariance of familiarity) revealed evidence suggesting that these assumptions are violated in many circumstances. In a final section, we introduce a more general model for quantifying consciously controlled versus automatic retrieval processes and show that the original PDP formulation is a special case that is obtained by making simplifying but probably unjustified assumptions. We hope that this paper will stimulate the development of more advanced and alternative investigative methods for dissociating processes.
Article
According to Martin and Levey (1987) evaluative conditioning is different from signal learning, i.e. the acquisition of knowledge about predictive relations between environmental events. The hypothesis was tested that evaluative conditioning, unlike signal learning, does not require awareness of the CS-US contingency. In three pilot experiments it was demonstrated that pairing neutral stimuli with either liked or disliked stimuli is sufficient to change neutral stimuli into a positive or negative direction. As indicated by postconditioning recognition questionnaires, this evaluative shift did not require and was not even influenced by contingency awareness. These findings were replicated and corroborated in an experiment, using a concurrent awareness assessment procedure and more fine-grained evaluative response measurements. The relevance of this conditioning without contingency awareness is discussed in the context of recent information processing models of Pavlovian conditioning.
Article
Baeyens, Eelen, and van den Bergh (1989) make the following two claims: (1) the changes in evaluative judgements reported by Martin and Levey (1978) represent a reliable form of conditioning; and (2) that for such conditioning to occur it is not necessary that the subject should be aware of the contingencies between the stimuli. We argue that neither of these claims is supported by the evidence. We present the results of an experiment which challenge the first claim, and we discuss theoretical and methodological reasons why the second claim is difficult to substantiate. We then discuss the role of cognition in Pavlovian conditioning, and argue that there are major conceptual difficulties implicit in cognitive theories of conditioning. Finally, we claim that there is little reason to believe that the transfer of affect from one stimulus to another in a conditioning experiment is cognitively mediated.
Article
In studies on hidden-covariation detection (HCD), it is demonstrated that humans may be influenced by covariations between stimuli, without acquiring any conscious or “explicit” knowledge about the crucial relations (e.g. Lewicki, Hill, & Sasaki, 1989). Even though not considered to be of any consequence, in the majority of studies the crucial X-Y covariation is embedded in a propositional structure of the type “X is a Y”. In the experiments reported here, however, the possibility of HCD was studied in a situation implying mere spatio-temporal co-occurrence between two nonverbal stimuli X and Y. Also, we investigated whether high imagery ability facilitates performance on an evaluative HCD task. While performing an attention-consuming distraction task, good and poor imagers were first exposed to a covariation between the line thickness (thick/thin) of a geometric figure and the valence (positive/negative) of a subsequently presented slide. In the test phase, subjects were required to express their subjective evaluation of a series of stimuli which differed in line thickness. In a series of three experiments, it was demonstrated that (a) even though none of the subjects was evidenced to have acquired any explicit knowledge about the X-Y covariation, (b) poor imagers’ evaluations of the test stimuli were clearly influenced by the hidden acquisition covariation, whereas contrary to expectations, good imagers only evidenced a non-significant tendency for HCD; (c) moreover, the HCD effect in poor imagers manifested itself in the form of an evaluative contrast, mirroring the acquisition contingency. The data further suggested that (d) the evaluative contrast phenomenon is a performance rather than a learning issue. Finally, it is argued that their may exist a fundamental conceptual similarity between the HCD paradigm used in this study and the standard Pavlovian or Evaluative Conditioning paradigm.
Article
Several studies (e.g., Nissen & Bullemer, 1987) claimed that reaction times to a repeating sequence may improve although subjects are not aware of the repeating sequence. Perruchet and Amorim (1992) pointed out that the measure of awareness involved in these studies was inadequate (e.g., subjects were not even explicitly asked to retrieve the repeating sequence), and they showed that the dissociation in normal subjects no longer held when awareness was assessed by recall or recognition tests. In this reply, we show that Cohen and Curran's (1993) criticisms of the validity of Perruchet and Amorim's tests and of the theoretical implications of their results are either without foundation or unfalsifiable. We also show that the new experiment by Willingham, Greeley, and Bardone (1993) does not demonstrate dissociation. Both comments further illustrate the widespread uncritical acceptance of dissociation, which probably originates from, but is not theoretically justified by, evidence available for dissociation in amnesic patients.
Article
Fifty-five patients were assigned randomly to receive either a total i.v. anaesthetic based on a two-stage infusion of etomidate plus increments offentanyl or a regimen based on inhaled nitrous oxide with i.v. fentanyl increments. Using the isolated forearm technique, 44% of the nitrous oxide group were found to be wakeful at some time during surgery, whereas only 7% of the etomidate group were wakeful. There was one case of awareness in the nitrous oxide group.
Article
Three replications of a double-blind experiment tested subliminal audiotape products that were claimed to improve memory or to increase self-esteem. Conditions of use adhered to manufacturers' recommendations, and subjects (N = 237) were limited to persons who desired the effects offered by the tapes. Actual content and labeled content of tapes were independently varied, so that some subjects who believed they were using memory tapes were actually using self-esteem tapes, and vice versa. After a month of use, neither the memory nor the self-esteem tapes produced their claimed effects. Nevertheless, a general improvement for all subjects in both memory and self-esteem (a nonspecific placebo effect) was observed, and more than a third of the subjects had the illusion of improvement specific to the domain named on the tape's label.
Article
Investigated the effects of changing various aspects of simple artificial languages during a learning task. Changes in the syntactic structure of the stimulus items seriously interfered with Ss' (3 male undergraduates) memory performance on a transfer task. Changes in the explicit symbols used to make up the stimulus items produced little or no interference. It was argued that Ss learn artificial languages by learning the abstract structure of the "sentences" in the language rather than by learning to string together explicit symbols.
Article
Tests for implicit memory seem to be rather insensitive to the amount of attention given to stimuli during study. In the experiment reported here, the effect of a complete absence of attention during presentation of stimulus material on implicit memory performance was studied. Surgical patients were auditorily presented with exemplars of word categories during general anaesthesia. At the earliest convenient time after surgery, they were requested to generate category exemplars. Although none of the patients expressed any conscious recollection of events during the surgical episode, experimental patients generated significantly more critical exemplars than a control group. Apparently, information presented during anaesthesia can influence post-operative performance in an implicit memory task. Repetition priming seems possible even in the absence of attentional processing at the time of encoding. It is argued that the nature of the unattended encoding process can best be described as the automatic activation and strengthening of pre-existing memory representations.
Article
This study examined implicit memory for words presented during sleep. Ten experimental subjects were presented with word pairs including a homophone and a close associate (e.g., “tortoise-hare”) and with category-instance pairs (e.g., “bird-cardinal”) during REM or Stage 2 sleep and tested immediately afterward. Twelve control subjects underwent the same procedure while awake. Unlike the controls, subjects in the sleeping condition showed no learning effects on the implicit memory tasks. Recall and recognition were observed in a few cases, but only when presentation was immediately followed by arousal.