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1.
We present and test an instance model of associative learning. The model, Minerva-AL, treats associative learning as cued recall. Memory preserves the events of individual trials in separate traces. A probe presented to memory contacts all traces in parallel and retrieves a weighted sum of the traces, a structure called the echo. Learning of a cue–outcome relationship is measured by the cue’s ability to retrieve a target outcome. The theory predicts a number of associative learning phenomena, including acquisition, extinction, reacquisition, conditioned inhibition, external inhibition, latent inhibition, discrimination, generalization, blocking, overshadowing, overexpectation, superconditioning, recovery from blocking, recovery from overshadowing, recovery from overexpectation, backward blocking, backward conditioned inhibition, and second-order retrospective revaluation. We argue that associative learning is consistent with an instance-based approach to learning and memory.  相似文献   

2.
Associative learning theories assume that cue interaction and, specifically, retrospective revaluation occur only when the target cue is previously trained in compound with the to-be-revalued cue. However, there are recent demonstrations of retrospective revaluation in the absence of compound training (e.g., Matute &; Pineño, 1998a, 1998b). Nevertheless, it seems reasonable to assume that cue interaction should be stronger when the cues are trained together than when they are trained apart. In two experiments with humans, we directly compared compound and elemental training of cues. The results showed that retrospective revaluation in the elemental condition can be as strong as and, sometimes, stronger than that in the compound condition. This suggests that within-compound associations are not necessary for retrospective revaluation to occur and that these effects can possibly be best understood in the framework of general interference theory.  相似文献   

3.
When retrospective revaluation phenomena (e.g., unovershadowing: AB+, then A?, then test B) were discovered, simple elemental models were at a disadvantage because they could not explain such phenomena. Extensions of these models and novel models appealed to within-compound associations to accommodate these new data. Here, we present an elemental, neural network model of conditioning that explains retrospective revaluation apart from within-compound associations. In the model, previously paired stimuli (say, A and B, after AB+) come to activate similar ensembles of neurons, so that revaluation of one stimulus (A?) has the opposite effect on the other stimulus (B) through changes (decreases) in the strength of the inhibitory connections between neurons activated by B. The ventral striatum is discussed as a possible home for the structure and function of the present model.  相似文献   

4.
Although it is thought that within-compound associations are necessary for the occurrence of both backward blocking and unovershadowing, it is not known whether this variable plays a similar role in mediating the two phenomena. Similarly, the roles of within-compound associations in forward blocking and in reduced overshadowing have not been tested independently. The present experiments evaluated how the strength of within-compound associations affects backward blocking, unovershadowing, forward blocking, and reduced overshadowing. Using an allergy task, the strength of within-compound associations was varied by taking advantage of the participants’ prior knowledge of common and uncommon food pairings. Backward blocking and unovershadowing effects were present only when highly memorable compound cues were used. Moreover, the magnitudes of both retrospective revaluation effects were affected by the strength of within-compound associations. Forward blocking and reduced overshadowing effects were independent of within-compound associations. These results have important theoretical implications for causal learning research.  相似文献   

5.
Dickinson and Burke (1996) proposed a modified version of Wagner’s (1981) SOP associative theory to explain retrospective revaluation of human causal judgments. In this modified SOP (MSOP), excitatory learning occurs when cue and outcome representations are either both directly activated or both associatively activated. By contrast, inhibitory learning occurs when one representation is directly activated while the other is associatively activated. Finite node simulations of MSOP yielded simple acquisition, overshadowing, blocking, and inhibitory learning under forward contingencies. Importantly, retrospective revaluation was predicted in the form of unovershadowing and backward inhibitory learning. However, MSOP did not yield backward blocking. These predictions are evaluated against the relevant empirical evidence and contrasted with the predictions of other associative theories that have been applied to retrospective revaluation of human causal and predictive learning.  相似文献   

6.
Previous research has demonstrated that discrete cues presented during extinction of a conditioned response (extinction cues) subsequently reduce spontaneous recovery and the renewal effect. In order to assess whether an extinction cue’s effect is due to conditioned inhibition, the effect of pairing an extinction cue with food on the cue’s capacity to modulate spontaneous recovery was investigated in an appetitive conditioning experiment with rats. Conditioned inhibitors paired with the unconditioned stimulus lose their potential to inhibit responding. The food-paired extinction cue did not lose its potential to reduce spontaneous recovery. In fact, it reduced spontaneous recovery more than did an extinction cue that was not paired with food. The results indicate that extinction cues attenuate postextinction recovery of conditioned responding through a mechanism other than conditioned inhibition. The cue’s action appears to be similar to that of serial negative occasion setters. Theories of spontaneous recovery and the relationship of extinction cues to other modulatory stimuli are discussed.  相似文献   

7.
In the present experiments, we examined the role of within-compound associations in the interaction of the overshadowing procedure with conditioned stimulus (CS) duration, using a conditioned suppression procedure with rats. In Experiment 1, we found that, with elemental reinforced training, conditioned suppression to the target stimulus decreased as CS duration increased (i.e., the CS duration effect), whereas, with compound reinforced training (i.e., the overshadowing procedure), conditioned suppression to the target stimulus increased as CS duration increased. In subsequent experiments, we replicated these findings with sensory preconditioning and demonstrated that extinction of the overshadowing stimulus results in retrospective revaluation with short CSs and in mediated extinction with long CSs. These results highlight the role of the duration of the stimulus in behavioral control. Moreover, these results illuminate one cause (the CS duration) of whether retrospective revaluation or mediated extinction will be observed.  相似文献   

8.
Rats were trained in a triangular water maze in which a compound of geometric and landmark cues indicated the position of a submerged platform. Rats that then underwent revaluation of the geometric cues in the absence of the landmarks subsequently failed to discriminate between the landmarks. In contrast, those animals that received geometry training consistent with their previous experience of the geometry–landmark compound continued to discriminate the landmark cues. The experiment showed that within-compound associations had formed between the geometry and landmarks, and that representations of absent geometric cues could be evoked via presentation of the landmark cues alone. We argue that these evoked representations of the absent geometry cues can counteract any overshadowing of the landmark by geometry cues, and may sometimes result in potentiation. The results of this study do not support theories of cue-competition failure based on independent cue processing, but remain readily explicable by appeal to an account based on within-compound associations.  相似文献   

9.
It is said that “absence makes the heart grow fonder.” But, when and why does an absent event become salient to the heart or to the brain? An absent event may become salient when its nonoccurrence is surprising. Van Hamme and Wasserman (1994) found that a nonpresented but expected stimulus can actually change its associative status—and in the opposite direction from a presented stimulus. Associative models like that of Rescorla and Wagner (1972) focus only on presented cues; so, they cannot explain this result. However, absent cues can be permitted to change their value by assigning different learning parameters to present and absent cues. Van Hamme and Wasserman revised the Rescorla-Wagner model so that the α parameter is positive for present cues, but negative for absent cues; now, changes in the associative strength of absent cues move in the opposite direction as presented ones. This revised Rescorla-Wagner model can thus explain such otherwise vexing empirical findings as backward blocking, recovery from overshadowing, and backward conditioned inhibition. Moreover, the revised model predicts new effects. For example, explicit information about the absence of nonpresented cues should increase their salience (that is, their negative α value should be larger), leading to stronger associative changes than when no explicit mention is made of cue absence. Support for this prediction is detailed in a new causal judgment experiment in which participants rated the effectiveness of different foods’ triggering a patient’s allergic reaction. Overall, these and other findings encourage us to view human causal learning from an associative perspective.  相似文献   

10.
Six experiments with color-odor compounds failed to produce convincing evidence of blocking in honeybees even when the possibility of masking by within-compound association could be discounted. The parsimonious assumption that the components of a compound stimulus gain and lose associative strength independently with reinforcement and nonreinforcement of the compounds (which the experiments were designed to challenge) remains tenable for color-odor compounds, although perhaps not for intramodal compounds.  相似文献   

11.
Five experiments used an autoshaping procedure with pigeon subjects to explore the consequences of separate-element presentation for within-compound associations. When a keylight compound had initially been reinforced, separate presentation of one element reduced responding to the other. This was true whether that separate-element presentation was itself reinforced or nonreinforced. That suggests that the detrimental effect of separate-element presentation results from an effect on the within-compound association, rather than one on the association of either element with the US. When the compound had initially been nonreinforced, a moderate level of reinforcement of one element resulted in responding to the other element. However, more extensive reinforcement reduced that responding. Moreover, an attempt to reverse the adverse consequences of extensive separate-element presentation by further exposure to the compound was not successful. These results comment on the associative mechanisms underlying performance in sensory preconditioning and related paradigms.  相似文献   

12.
Models of associative learning differ in their predictions concerning the symmetry of generalization decrements. Whereas Pearce’s (1994) configural model predicts the same response decrement after adding elements to and after removing elements from a previously trained stimulus, elemental models, such as the replaced elements model and Harris’s (2006) model, anticipate more of a decrement for removing than for adding elements. In three contingency learning experiments, we manipulated the motion and the spatial arrangement of colored dots in order to induce configural or elemental processing by perceptual grouping. The results reliably showed symmetrical decrements for the added and removed groups. The manipulations of the stimuli had no effect on stimulus processing. This is in line with Pearce’s configural model, but it is at variance with the elemental models and previous studies.  相似文献   

13.
Two fear-conditioning experiments with rats assessed whether retrospective revaluation, which has been observed in cue competition (i.e., when compounded cues are followed with an outcome), can also be observed in retroactive cue interference (i.e., when different cues are reinforced in separate phases with the same outcome). Experiment 1 found that after inducing retroactive cue interference (i.e., X-outcome followed by A-outcome), nonreinforced presentations of the interfering cue (A) decreases interference with responding to the target cue (X), just as has been observed in retrospective revaluation experiments in cue competition. Using the opposite manipulation (i.e., adding reinforced presentations of A), Experiment 2 demonstrated that after inducing retroactive cue interference, additional reinforced presentations of the interfering cue (A) increases interference with responding to the target cue (X); alternatively stated, the amount of interference increases with the amount of training with the interfering cue. Thus, both types of retrospective revaluation occur in retroactive cue competition. The results are discussed in terms of the possibility that similar associative mechanisms underlie cue competition and cue interference.  相似文献   

14.
The associative changes that occur in extinction were investigated in four instrumental learning experiments. Experiment 1 used transfer based on a shared outcome to detect the continued presence of response-outcome (R-O) and stimulus-outcome (S-O) associations after a response had been nonreinforced in the presence of its controlling stimulus. Experiments 2–4 found that extinction resulted in the learning not to make a particular response in the presence of a particular stimulus, despite those continued R-0 and S-0 associations. These results suggest that extinction may superimpose upon those original outcome associations an inhibitory S-R association.  相似文献   

15.
Three different techniques were employed to analyze the associative structures mediating performance on an instrumental biconditional discrimination. In all three experiments, rats were trained concurrently on two tasks in which different stimuli signaled which one of two responses would be followed by reward. In each task, one response was rewarded in one stimulus and the other response was rewarded in the other stimulus. Correct responses earned pellets in one task and sucrose in the other task. The transfer procedure was used in Experiment 1A to identify whether or not an association developed between a biconditional discriminative stimulus and its instrumental outcome. Evidence was obtained that a biconditional cue elevated preferentially a new response trained with the same outcome. Experiments 1B and 3 examined the potential contribution of this stimulus-outcome association to biconditional performance by training the biconditional cues as signals (S-s) for the nonreinforcement of a different response. There was no evidence that this operation interfered with the ability of a biconditional cue to control performance of its correct response. In Experiments 1B and 2, the value of the instrumental outcome was reduced in an attempt to assess the contribution of stimulus-response associations to performance on the biconditional discrimination. The results of Experiments 1B and 2 reveal that correct responses were depressed following devaluation of the outcome used to train them, suggesting that learning about the response-outcome relation occurs. The implications of these results for binary and hierarchical models of instrumental learning are discussed.  相似文献   

16.
The present study aims to analyse the complex relationships between the relevant constructs of students’ demographic background, perceptions, learning patterns and (proxy measures of) learning outcomes in order to delineate the possible direct, indirect, or spurious effects among them. The analytical methodology is substantively framed against the studies of Richardson (British Journal of Educational Psychology 76:867–893, 2006, Higher Education 54:385–416, 2007) that utilised a regression-based methodology to infer the possible causal relationships among the relevant learning constructs. A composite research instrument, written in Chinese and derived from the Inventory of Learning Styles (ILS) and the Course Experience Questionnaire (CEQ), was used to collect students’ feedback on their perceptions of the learning environment and their learning patterns. Valid responses were obtained from 1,572 students studying at six institutions in the post-secondary education sector in Hong Kong, a new response-context for both the CEQ and the ILS. In adapting the research instruments to a new Chinese response-context, the findings are generally consistent with those reported in other published works (e.g. no relationship between students’ demographic background and their satisfaction with the programme, and a significant relationship between students’ exhibition of undirected learning patterns and low expected performance), but there are also some noteworthy discrepancies. The findings therefore buttress the confidence with which an ILS-based General Theoretical Model of student learning, adapted from Richardson (British Journal of Educational Psychology 76:867–893, 2006, Higher Education 54:385–416, 2007), may be used to conceptualise and interpret the dynamics of variation across different cultural response-contexts. While the CEQ provides some valuable complementary insights, it is an instrument that requires further development in the response-context of the present study.  相似文献   

17.
The aim of the paper is to advance understanding of in-service learning and skills sector trainee teachers’ learning and propose ways of improving their learning. A conceptual framework is developed by extending Billett’s (International Journal of Educational Research 47:232–240, 2008) conceptualisation of workplace learning, as a relationally interdependent process between the opportunities workplaces afford for activities and interactions and how individuals engage with these, to a third base of participation, the affordances of the initial teacher education course. Hager and Hodkinson’s (British Educational Research Journal 35:619–638, 2009) metaphor of ‘learning as becoming’ is used to conceptualise the ways trainees reconstruct learning in a continuous transactional process of boundary crossing between course and workplace. The findings of six longitudinal case studies of trainees’ development, and evidence from other studies, illustrate the complex interrelationships between LSS workplace affordances, course affordances and trainee characteristics and the ways in which trainees reconstruct learning in each setting. The experience of teaching and interacting with learners, interactions with colleagues, and access to workplace resources and training are important workplace affordances for learning. However, some trainees have limited access to these affordances. Teaching observations, course activities and experiences as a learner are significant course affordances. Trainees’ beliefs, prior experiences and dispositions vary and significantly influence their engagement with course and workplace affordances. It is proposed that better integration of course and workplace learning through guided participation in an intentional workplace curriculum and attention to the ways trainees choose to engage with this, together with the use of practical theorising has the potential to improve trainee learning.  相似文献   

18.
Today’s emphasis on using children’s literature as a tool to teach reading and writing sub-skills distracts teachers’ attention from looking to children’s books for their historical role in helping children navigate the intellectual, social, and emotional terrains of childhood. This article argues, first, that early childhood educators must remain fluent in the use of literature that supports young children’s psychosocial development. Second, teachers must establish criteria for choice. By way of example, it examines two popular books for young children, Sendak’s (1963) Where the Wild Things Are [New York: HarperCollins Publishers] and Shannon’s (1998) No, David! [New York: Blue Sky Press] Three theoretical perspectives guide the analysis. The first combines Dewey’s (1938/97) [Experience and education. New York:Touchstone] impetus for learning and Vygotsky’s (1978) [Mind in society. Cambridge: Harvard University Press] theory that learning precedes development through scaffolded social interaction. The second is Erikson’s (1950, 1985) [Childhood and society. New York: W. W. Norton & Company, Inc.] theory of psychosocial development in light of the 4–6-year-old’s drive towards self-regulation, control, and independence. The third is Rosenblatt’s (1978) [The reader, the text, the poem. Urbana, IL: National Council of Teachers of English] transactional nature of reading.  相似文献   

19.
This study considers the case of a tutor whose students repeatedly evidenced significantly superior critical thinking in summative assessment. For the purpose of surfacing appropriate pedagogical action to promote critical thinking (Bassey, Case Study Research in Educational Settings, 1999), the singularity of one tutor’s reported pedagogical practice was explored through focus-group discussion. Qualitative analysis of the data, theoretically informed by phenomenography, suggested that the tutor’s reported practice, when compared with that of two peers, revealed clear pedagogical intentions to be necessary for teaching critical thinking; and that these intentions can be explained through the literatures on epistemic activity, metacognitive regulative behaviour and student-centred learning. It is argued that a synthesised understanding of the literature that explores the nature and purpose of critical thinking —as outlined in the first part of this paper—is a prerequisite for constructing domain-specific pedagogical intentions for developing learners’ critical thinking, and that it is this extensive psychologically informed knowledge base which attenuates the risk of educationally important aspects of learning being overlooked. (De Corte, Learning and Instruction 10:249–266, 2000).  相似文献   

20.
An attentional-associative model (Schmajuk, Lam, & Gray Journal of Experimental Psychology: Animal Behavior Processes, 22, 321–349, 1996) assumes that nonreinforced presentations of an inhibitory conditioned stimulus (CS) do not decrease its inhibitory associations. However, the model predicts that extended presentations will decrease attention to the inhibitor, thereby decreasing both (1) the expression of its inhibitory power in a summation test and (2) the rate of acquisition in a retardation test. The model also predicts that subsequent presentations of the inhibitory CS with a novel CS will increase both (1) and (2). Using a predictive learning design in humans, Experiment 1 examined the predictions involving the summation tests, whereas Experiments 2 and 3 examined the predictions involving the retardation tests. Experimental results were in agreement with the predictions of the model.  相似文献   

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