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1.
In a Pavlovian conditioning situation, an initially neutral stimulus may be made excitatory by nonreinforced presentations
in compound with an established conditioned excitor [i.e., second-order conditioning (SOC)]. The established excitor may be
either a punctate cue or the training context. In four conditioned suppression experiments using rats, we investigated whether
SOC phenomena parallel other cue interaction effects. In Experiment 1, we found that the response potential of a target stimulus
was directly related to the intertrial interval when SOC was mediated by a punctate cue, and inversely related to the intertrial
interval when SOC was mediated by the training context. Experiment 2 demonstrated that punctate- and context-mediated SOC
are oppositely affected by posttraining context extinction, and Experiments 3 and 4 demonstrated that context- and punctate-mediated
SOC are differentially affected by conditioned stimulus (Experiment 3) and unconditioned stimulus (Experiment 4) preexposure
treatments. These findings parallel phenomena in conditioned inhibition and cue competition situations. 相似文献
2.
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
3.
Using rats in a conditioned lick suppression preparation, six experiments were conducted in which the subjects were exposed to a single tone-LiCl pairing. Despite evidence from tone-shock conditioning that the tone was an adequate conditioned stimulus and evidence from taste-LiCl conditioning that the LiCl was an adequate unconditioned stimulus, no suppression to the tone was observed following the tone-LiCl pairing, a finding consistent with prior cue-to-consequence research. In each experiment, subjects receiving a tone-LiCl pairing were subsequently exposed to either the tone or LiCl outside the conditioning context in an attempt to reactivate a potentially latent tone-LiCl association. The parameters of these reminder treatments were chosen on the basis of their previously proven effectiveness in reversing such performance deficits as blocking, overshadowing, latent inhibition, and experimental amnesia. Although a variety of stimulus parameters were used in an effort to reverse the cue-to-consequence deficit, none of the experiments detected any tendency towards suppression by reminded subjects exposed to a tone-LiCl pairing. This uniform lack of reminder-induced recovery suggests that cue-to-consequence deficits reflect true acquisition failure rather than poor retrievability. 相似文献
4.
Douglas C. Brooks Matthew I. Palmatier Eliseo O. Garcia Jessica L. Johnson 《Learning & behavior》1999,27(1):77-88
The effect of an auditory cue presented during extinction on spontaneous recovery of a conditioned taste aversion was investigated in three experiments. Experiment 1 demonstrated that the presence of the cue during extinction did not influence saccharin consumption during that phase, and that an aversion to saccharin in the absence of the cue was stronger at 18 days than at 1 day after extinction, representing spontaneous recovery rather than a renewal effect. Experiment 2 showed that a cue presented during extinction and testing reduced spontaneous recovery. Experiment 3 replicated that effect and showed that it depended on the cue’s correlation with extinction and not on an unconditioned effect; cues that had been presented during or prior to conditioning did not reduce spontaneous recovery when presented during testing. The cue’s potential to reduce spontaneous recovery through conditioned inhibition or configural cue learning is discussed, as is the possibility that the cue retrieves a saccharin extinction memory in a manner consistent with Bouton’s (1993) account of spontaneous recovery. 相似文献
5.
The blocking phenomenon was investigated in the sexual response system of male Japanese quail. Access to a live female quail served as the unconditioned stimulus (US). The same audiovisual cue served as the pretrained stimulus in all of the experiments. Following asymptotic conditioning of the audiovisual cue, a second conditioned stimulus (CS2) was added. In Experiment 1, CS2 was a rectangular wood block that had little or no resemblance to a female quail and could not support copulatory behavior. In Experiment 2, CS2 was a terrycloth object that had no quail parts but could support copulatory behavior, and, in Experiment 3, CS2 was a terrycloth object that had a taxidermically prepared head of a female quail added. The terrycloth-only object supported more rapid conditioning than did the wood block, but the blocking effect was obtained with both kinds of stimuli. Approach responding to the terrycloth + head object required pairing it with copulatory opportunity, and the terrycloth + head object supported at least as rapid conditioning as did the terrycloth-only object. However, responding to the terrycloth + head object was not blocked by the pretrained audiovisual cue. These results indicate that the blocking effect occurs in sexual conditioning even with stimulus objects that can support copulation. However, the addition of species-typical head cues to an object makes that object such a powerful stimulus that conditioned approach responding to it cannot be blocked by a previously conditioned arbitrary audiovisual cue. 相似文献
6.
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
7.
Peter C. Holland Judith S. A. Asem Connor P. Galvin Caitlin Hepps Keeney Melanie Hsu Alexandra Miller Vivian Zhou 《Learning & behavior》2014,42(1):1-21
Rats will approach and contact a lever whose insertion into the chamber signals response-independent food delivery. This “autoshaping” or “sign-tracking” phenomenon has recently attracted considerable attention as a platform for studying individual differences in impulsivity, drug sensitization, and other traits associated with vulnerability to drug addiction. Here, we examined two basic stimulus selection phenomena—blocking and overshadowing—in the autoshaped lever pressing of rats. Blocking and overshadowing were decidedly asymmetrical. Previously reinforced lever-extension conditioned stimuli (CSs) completely blocked conditioning to auditory cues (Exps. 1 and 2), and previously nonreinforced lever-extension CSs overshadowed conditioning to auditory cues. By contrast, conditioning to lever-extension CSs was not blocked by either auditory (Exp. 3) or lever-insertion (Exp. 4) cues, and was not overshadowed by auditory cues. Conditioning to a lever-insertion cue was somewhat overshadowed by the presence of another lever, especially in terms of food cup behavior displayed after lever withdrawal. We discuss several frameworks in which the apparent immunity of autoshaped lever pressing to blocking might be understood. Given evidence that different brain systems are engaged when different kinds of cues are paired with food delivery, it is worth considering the possibility that interactions among them in learning and performance may follow different rules. In particular, it is intriguing to speculate that the roles of simple cue–reinforcer contiguity, as well as of individual and aggregate reinforcer prediction errors, may differ across stimulus classes. 相似文献
8.
Delamater AR 《Learning & behavior》2012,40(1):1-23
A significant problem in the study of Pavlovian conditioning is characterizing the nature of the representations of events
that enter into learning. This issue has been explored extensively with regard to the question of what features of the unconditioned
stimulus enter into learning, but considerably less work has been directed to the question of characterizing the nature of
the conditioned stimulus. This article introduces a multilayered connectionist network approach to understanding how “perceptual”
or “conceptual” representations of the conditioned stimulus might emerge from conditioning and participate in various learning
phenomena. The model is applied to acquired equivalence/distinctiveness of cue effects, as well as a variety of conditional
discrimination learning tasks (patterning, biconditional, ambiguous occasion setting, feature discriminations). In addition,
studies that have examined what aspects of the unconditioned stimulus enter into learning are also reviewed. Ultimately, it
is concluded that adopting a multilayered connectionist network perspective of Pavlovian learning provides us with a richer
way in which to view basic learning processes, but a number of key theoretical problems remain to be solved, particularly
as they relate to the integration of what we know about the nature of the representations of conditioned and unconditioned
stimuli. 相似文献
9.
Anthony S. Rauhut Janice E. Mcphee Norma T. Dipietro John J. B. Ayres 《Learning & behavior》2000,28(1):92-108
In each of two experiments, we studied Pavlovian fear conditioning (as assessed by barpress conditioned suppression) in 32 albino rats. Following a two-stage cue-competition procedure (A+ then AX+), we subjected the competing cue (A) to conditioned inhibition training (B+, BA?) before testing the target cue (X). Conditioned inhibition training was designed to weaken the putative A-unconditioned stimulus (US) association, perhaps changing it to an A-no-US association. Performance-deficit theories of cue competition, such as comparator theory and retrieval-interference theory, predict that such procedures should weaken cue competition, causing Conditioned Stimulus X (CS X) to evoke strong responding. The same prediction can be deduced from recent acquisition-focused models (Dickinson &; Burke, 1996; Van Hamme &; Wasserman, 1994). In opposition to this prediction, however, we found in both experiments that conditioned inhibition training had no detectable effect on cue competition even though it successfully abolished conditioned responding to CS A. In Experiment 2, moreover, we found evidence against the hypothesis that the weak response to CS X was due to generalization decrement rather than to cue competition. Results favor early learning-deficit theories of cue competition over performance-deficit theories and over the recent acquisition-focused models. 相似文献
10.
Two conditioned lick suppression experiments with rats used feature-negative training (A-footshock trials intermixed with
nonreinforced XA presentations) to analyze the role of the number of XA compound presentations and the temporal relationship
of the elements within the compound (simultaneous or serial) as determinants of the resulting behavioral control. Second-order
conditioning (i.e., excitatory behavioral control by X) was observed to decline as the number of XA compound trials was increased.
This decline was more rapid if X and A were presented simultaneously, as opposed to serially (i.e., X before A; Experiment
1). Conditioned inhibition to X, as assessed by a summation test (Experiment 1) and a retardation test (Experiment 2), increased
with the number of XA trials and did so more quickly for simultaneous than for serial pairings of X and A. The results help
to clarify previously discrepant findings regarding factors that promote excitation versus inhibition with this protocol. 相似文献
11.
In a conditioned suppression experiment, rats received a single, massed session of conditioning in which one backward conditioned inhibitory stimulus (CS-) followed shocks that were signaled by a visual cue, and a second backward CS-followed shocks that were unsignaled. Conditioning was preceded by a preexposure phase in which some groups of rats were preexposed to unsignaled shock, while others were not preexposed and remained in the experimental apparatus in the absence of shock. The groups were further distinguished by whether US preexposure and conditioning occurred in the same or different contexts, and by whether conditioning began immediately or after a 24-h rest period in the home cage. Although the conditioning itself was effective in establishing the visual cue as a conditioned excitor in the nonpreexposed groups, it was not effective in establishing the two backward cues as reliable inhibitors with either signaled or unsignaled USs. After 210 US preexposures, however, the same conditioning sessions did yield conditioned inhibition to both CS-s. A 24-h rest period in the home cage reduced the magnitude of, but did not completely abolish, the facilitative effect of US preexposure on inhibitory conditioning. Other tests demonstrated that US preexposure had retarded excitatory conditioning to the visual cue. This interference with excitatory conditioning was unchanged in magnitude after the 24-h rest period. The facilitative effect of US preexposure on backward inhibitory conditioning, and the interference effect on excitatory conditioning, were both eliminated by a change in context between US preexposure and conditioning. These observations encourage predominantly associative accounts of the effects, but allow for a small nonassociative habituation component. 相似文献
12.
Two conditioned suppression experiments with rats were conducted to determine whether the spontaneous recovery and renewal
that are commonly observed in retroactive outcome interference (e.g., extinction) also occur in retroactive cue interference.
Experiment 1 showed that a long delay between Phase 2 (the interfering phase) and testing produces a recovery from the cue interference
(i.e., the delay enhanced responding to the target cue trained in Phase 1), which is analogous to the spontaneous recovery
effect observed in extinction and other retroactive outcome interference procedures. Experiment 2 showed that, when target and interfering cues are trained in separate contexts and testing occurs in a different but familiar
context, a recovery from the cue interference is also observed (i.e., the context shift enhanced responding to the target),
which is analogous to ABC renewal from extinction. The results are discussed in terms of the possibility that similar associative
mechanisms underlie cue and outcome interference. 相似文献
13.
Two experiments with rabbits investigated the concordance of two measures of conditioning, eyeblink and potentiated startle, during a blocking sequence with paraorbital shock reinforcement. In both, a shift in the locus of shock from one eye to the other between the conditioning of an element and a compound of that element and a new cue had differential effects on the two measures of conditioning to the new cue. When the shock was unchanged, diminished conditioning in relation to controls (i.e., blocking) was observed on both measures. When the shock was changed, little conditioning was observed in startle, but control-equivalent amounts were observed in eyeblink (i.e., blocking occurred on the former but not the latter). The results are interpreted as showing a dissociation of the associative learning involving the emotive features of Pavlovian reinforcers and that involving the remaining sensory-perceptual features, and more compatible with a diminished US-processing, than with a CSprocessing, view of blocking. 相似文献
14.
Mary Ann Balaz Sharon Capra Wesley J. Kasprow Ralph R. Miller 《Learning & behavior》1982,10(2):242-248
Previous research in our laboratory has found superior performance when classically conditioned responses are observed in the training context as opposed to outside it, even when direct context-US associations have been minimized by either the choice of conditioning parameters or extinction to the context. The present experiment used latent inhibition of the conditioning context as an alternative method of examining contextual cue effects in the absence of appreciable direct context-US associations. Water-deprived rats received tone-footshock pairings in one of two distinctly different apparatuses, but all were tested in a common apparatus. Animals conditioned in the test enclosure displayed more lick suppression than those conditioned outside the test enclosure. Other animals tested without the tone present also exhibited more suppression if conditioning had occurred in the test context rather than outside it, indicating that direct associations between the conditioning context and shock had been formed. However, when formation of direct associations to the conditioning context was attenuated in additional animals through extensive preexposure to the context prior to conditioning, more suppression to the tone was still seen when conditioning had occurred in the test context rather than outside it. These results add support to the position that the training context augments recall even when direct associations between the context and the US are attenuated. The phenomenon is discussed in terms of facilitated retrieval of nominal CS-US associations, configural retrieval cues, and conditional discriminations. 相似文献
15.
This article introduces a new model of Pavlovian conditioning, attention as an acquisition and performance variable (AAPV), which, like several other so-called attentional models, emphasizes the role of variation of cue salience, together with associative strength, in accounting for conditioning phenomena. AAPV is primarily (but not exclusively) a performance-focused model in that it assumes not only that both the saliences and associative strengths of cue representations change during acquisition, but also that they are both influential at the time of test in determining responding. Different weights are given to the representations’ associative strengths according to the representations’ respective saliences at test. The model also treats the representation of a stimulus that is directly activated by presentation of that stimulus as distinct from the representation of the same stimulus that is activated by presenting a companion of the stimulus. Additionally, extinction is viewed as resulting from a decrease in the salience of the cue’s representation, rather than a decrease in associative strength. Simulations of several Pavlovian phenomena are presented in order to illustrate the model and assess its robustness. 相似文献
16.
In a series of related experiments, we studied associative phenomena in snails (Helix aspersa), using the conditioning procedure of tentacle lowering. Experiments 1A and 1B demonstrated a basic conditioning effect in
which the pairing of an odor (apple) as the conditioned stimulus (CS) with the opportunity to feed on carrot as the unconditioned
stimulus (US) made snails exhibit increased levels of tentacle lowering in the presence of the CS. Experiments 2 and 3 showed
that the magnitude of the conditioning was reduced when snails were exposed to the CS prior to the conditioning trial (a latent
inhibition effect). Experiment 4 examined the effects produced by pairing a compound CS (apple—pear) with food presentations
and demonstrated the existence of an overshadowing effect between the two odors. Experiment 5 revealed that pairing one CS
with another previously conditioned stimulus increased tentacle lowering to the new CS (a second-order conditioning effect).
Finally, Experiment 6 showed that pairing two odors prior to conditioning of one of them promoted an increase in tentacle
lowering in response to the other (a sensory preconditioning effect). The results are discussed in terms of an associative
analysis of conditioning and its implications for the study of cognition in invertebrates. 相似文献
17.
Siegel, Allan, Hannah, and Crump (2009) demonstrated that cue interaction effects in human contingency judgments reflect processing that occurs after the acquisition
of information. This finding is in conflict with a broad class of theories. We present a new postacquisition model, the criterion-calibration
model, that describes cue interaction effects as involving shifts in a report criterion. The model accounts for the Siegel
et al. data and outperforms the only other postacquisition model of cue interaction, Stout and Miller’s (2007) SOCR model. We present new data from an experiment designed to evaluate a prediction of the two models regarding reciprocal
cue interaction effects. The new data provide further support for the criterion-calibration model. 相似文献
18.
Latent inhibition (LI), the retardation of Pavlovian acquisition after nonreinforced preexposure to the conditioned stimulus, is a popular paradigm for studying basic attentional and memory processes from both behavioral and neurobiological perspectives. It is argued that whether LI emerges depends on the behavioral measure used to index conditioning. An experiment with rats demonstrates that stimulus preexposure retards the development of sign-tracking responses directed at the stimulus, but not the development of goal-tracking responses directed at the site of food delivery. These results are consistent with models that explain LI in terms of a deficit in retrieval. 相似文献
19.
Male Japanese quail learned to approach a light that predicted visual exposure to a female quail. In Experiment 1, duration of visual exposure to the female did not systematically affect the speed or strength of conditioning. Introduction of an omission contingency for approach to the light after acquisition did not suppress conditioned approach relative to the performance of yoked controls. In Experiment 2, males learned to approach a light that predicted visual exposure to a female despite an omission contingency for approach in effect during acquisition. Experimental males were not slower to acquire the approach response under an omission contingency than were yoked controls. The findings indicate strong Pavlovian control of sexual conditioned approach in Japanese quail. 相似文献
20.
In three experiments with rats, we demonstrated that a conditioned response that is learned and extinguished in one context (Context A) can be renewed when the conditioned stimulus (CS) is tested in a second context (Context B). In Experiments 1 and 3, the effect was observed in conditioned suppression; in Experiment 2, it was produced in appetitive conditioning. The result occurs when Contexts A and B are equally familiar, equally associated with reinforcement, or equally associated with both reinforcement and nonreinforcement. The results extend the range of conditions known to produce the renewal effect, and they are consistent with the view that retrieval of extinction depends more on the context than does retrieval of conditioning. 相似文献