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1.
In an experiment with rats, an appetitive conditioning method was used to investigate the generality of the hypothesis that
extinction should arouse attention to contextual cues, resulting in all learning in that context becoming context specific.
Rats received appetitive conditioning with a tone either while extinction of a flasher occurred (Group With Extinction) or
while it did not (Group No Extinction). Half of each group was subsequently tested in extinction in the context in which training
had taken place or in a different context. The results revealed a three-way interaction of extinction and context with trials,
in a direction opposite to the one the hypothesis would suggest. When rats were tested in a different context, there was generally
better responding in Group With Extinction than in Group No Extinction. In the same context, there was generally lower responding
in Group With Extinction than in Group No Extinction. Subsequent testing showed an ABA recovery effect. Results are discussed
in terms of the challenges they pose for the revised retrieval theory presented by Callejas-Aguilera and Rosas (2011). 相似文献
2.
Rescorla RA 《Learning & behavior》2004,32(4):401-408
Four experiments found the magnitude of spontaneous recovery after extinction to be greater with a shorter interval between
initial conditioning and extinction. Experiments 1 and 2 used a Pavlovian magazine approach procedure with rat subjects, Experiment
3 used an instrumental training procedure with rats, and Experiment 4 used a sign-tracking procedure with pigeons. These results
are not anticipated by many accounts of spontaneous recovery that attribute it to the fading of learning that occurred during
extinction. 相似文献
3.
Studies of extinction in classical conditioning situations can reveal techniques that maximize the effectiveness of exposure-based
behavior therapies. In three experiments, we investigated the effect of varying the intertrial interval during an extinction
treatment in a fear-conditioning preparation with rats as subjects. In Experiment 1, we found less fear at test (i.e., more
effective extinction) when extinction trials were widely spaced, relative to intermediate or massed extinction trials. In
Experiment 2, we used an ABA renewal procedure and observed that spaced trials attenuated renewal of conditioned fear relative
to massed trials. In Experiment 3, we used a similar design, but instead of changing the physical context at the time of testing,
we interposed a retention interval after the extinction treatment to produce a change in the temporal context. The results
showed less spontaneous recovery of fear after spaced than after massed extinction trials. These results suggest that extinction
is more enduring when the extinction trials are spaced rather than massed. Although the benefits of spacing trials are small
when there is no contextual change from extinction to testing, a change in either physical or temporal context following massed
extinction trials leads to a recovery from extinction, which is reduced when the trials are spaced. 相似文献
4.
Four experiments were performed to explore the role of context in operant extinction. In all experiments, leverpressing in
rats was first reinforced with food pellets on a variable interval 30-s schedule, then extinguished, and finally tested in
the same and a different physical context. The experiments demonstrated a clear ABA renewal effect, a recovery of extinguished
responding when conditioning, extinction, and testing occurred in contexts A, B, and A, respectively. They also demonstrated
ABC renewal (where conditioning extinction and testing occurred in contexts A, B, and C) and, for the first time in operant
conditioning, AAB renewal (where conditioning, extinction, and testing occurred in contexts A, A, and B). The latter two phenomena
indicate that tests outside the extinction context are sufficient to cause a recovery of extinguished operant behavior and,
thus, that operant extinction, like Pavlovian extinction, is relatively specific to the context in which it is learned. AAB
renewal was not weakened by tripling the amount of extinction training. ABA renewal was stronger than AAB, but not merely
because of context A’s direct association with the reinforcer. 相似文献
5.
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
6.
In three experiments, we assessed the role of signals for changes in the consequences of cues as a potential account of the
renewal effect. Experiment 1 showed recovery of responding following extinction when acquisition, extinction, and test phases
occurred in different contexts. In addition, extinction treatment in multiple contexts attenuated context-induced response
recovery. In Experiment 2, we used presentations of an extraneous stimulus (ES), instead of context shifts, and found that
responding recovered from extinction only when the ES was presented both between acquisition and extinction and between extinction
and test. In Experiment 3, we used a reversal learning design in which, during training, two cues were first paired with different
outcomes, then paired with the alternative outcomes, and finally paired again with the original outcomes. In this experiment,
presentation, just prior to testing, of an ES that had previously been presented between the different phases produced an
expectation of reversal in the meaning of the cues. 相似文献
7.
Reinstatement after counterconditioning was examined in three experiments with rats. The rats received CS-shock pairings in Phase 1 and then CS-food pairings in Phase 2. When unsignaled shock was presented after appetitive conditioning, fear performance to the CS replaced food performance. This reinstatement effect depended on initial pairings of the CS and shock in Phase 1. It also depended on shock exposure occurring in the test context. The results parallel previous data obtained after extinction. Counterconditioning and extinction yield several parallel effects (spontaneous recovery, renewal, and now reinstatement) which suggest that Phase 2 does not destroy the learning acquired in Phase 1. 相似文献
8.
Lynn D. Devenport 《Learning & behavior》1998,26(2):172-181
Spontaneous recovery from extinction is a reliable result of two ingredients, variable training outcomes and the passage of time. Accounts of the phenomenon, which have come to focus on interference at the level of memory retrieval, have been based on simple associative learning tasks. The present study was designed to determine whether a more complex task—one requiring spatial mapping, timing, and patch assessment—would be subject to spontaneous recovery. Results showed that spontaneous recovery (1) makes a robust appearance in such tasks, (2) does not require interference among conflicting memories, but instead (3) requires ready access to training memories, and (4) is closely modeled by the temporal weighting rule, a quantitative model of patch choice that prescribes how value is best assigned to variable resources (L. D. Devenport & J. A. Devenport, 1994). 相似文献
9.
Rats were trained in a triangular-shaped pool to find a hidden platform that maintained a constant relationship with two sources
of information, an individual landmark and one part of the pool with a distinctive shape. In Experiment 1, shape learning overshadowed landmark learning but landmark learning did not overshadow shape learning in males, while landmark
learning overshadowed shape learning but shape learning did not overshadow landmark learning in females. In Experiment 2,
rats were pretrained either with the single landmark relevant or with the shape relevant, in the absence of the alternative
cue. Final test trials, without the platform, revealed reciprocal blocking only in females; in males, shape learning blocked
landmark learning, but not viceversa (Experiment 2a). In Experiment 2b, male rats received a longer pretraining with the single landmark relevant, and now landmark learning blocked shape learning.
The results thus confirm the claim that males and females partially use different types of spatial information when solving
spatial tasks. These results also agree with the suggestion that shape learning interacts with landmark learning in much the
same way as does learning about any pair of stimuli in a Pavlovian conditioning experiment. 相似文献
10.
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
11.
Thirty rats received 10 sessions of baseline training in which leverpressing was reinforced according to a variable-interval (VI) 60-sec schedule. Twenty-four of the subjects were then assigned to one of four groups that received five sessions of extinction, with groups being differentiated in a 2 by 2 factorial design on the basis of: (1) changes in stimuli accompanying transportation of subjects from home cages to the laboratory and placement in the apparatus, and/or (2) changes in contextual stimuli within the apparatus. During the sixth session of extinction, the transportational and contextual stimuli previously associated with baseline training were reinstated. The remaining six rats experienced changes in both transportational and contextual stimuli but were maintained on the VI 60-sec schedule of reinforcement. Changes in either transportational or contextual stimuli reduced resistance to extinction and spontaneous recovery, and substantial increments in responding occurred upon reinstatement of the transportational and contextual stimuli associated with baseline training. Evidence for summation of the two sources of stimulus change was obtained. Changes in transportational and contextual stimuli produced only a brief disruption in responding when reinforcement of leverpressing was continued. 相似文献
12.
In the blocking phase of three experiments, rats had to find a submerged platform beneath a spherical landmark in one corner
of a triangular pool. Prior to this treatment, they were required to find the platform relative to either a sphere above it
(blocking groups) or a rod attached to it (control groups). The position of the platform changed from trial to trial for the
initial training. The sphere did not restrict learning about the geometric cues provided by the triangular arena in the blocking
phase when 12 sessions of initial training took place in either the triangular (Experiment 1) or a circular (Experiment 3)
pool. Blocking was observed, however, after 24 sessions of initial training in either the triangular (Experiment 2) or the
circular (Experiment 3) pool. Thus, blocking of geometric cues by a landmark is possible after extended initial training with
the blocking cue. 相似文献
13.
Robert A. Rescorla 《Learning & behavior》1996,24(1):11-18
Four experiments explored the increase in an instrumental response (R) with time after it had been subjected either to extinction or to training with a second outcome (O). Experiment 1 found less performance of an extinguished response immediately after extinction than after a 7-day delay (spontaneous recovery). Experiments 2–4 found a similar difference when training with a second outcome replaced extinction, despite the failure of that replacement to itself undermine performance. Similar results did not occur when the second outcome was identical to that used in initial training. These results suggest that training with a novel outcome generates a decremental process that is not directly observable but that dissipates with time. 相似文献
14.
The mechanisms of extinction were examined by reducing the intensity of the unconditioned stimulus (US) after acquisition training to determine whether such reductions lie on a continuum with CS-alone extinction. The experiments revealed that reductions in US intensity yielded extinction-like effects. Specifically, there were proportional reductions in the daily mean level of responding across sessions. There were also persistent within-session declines and between-session increases of responding analogous to spontaneous recovery. Surprisingly, even when US intensity was held constant, within-session declines and between-session increases were apparent. The results are discussed with respect to possible contributions from unlearning, new learning, generalization decrement, and nonassociative loss, especially CS-specific attentional changes and CR-specific reactive inhibition. 相似文献
15.
In Experiments 1 and 2, rats were trained in a Morris water maze to locate a hidden platform, the location of which in the circular pool was defined by four visual landmarks (A, B, C, and D), spaced at equal intervals around the edge of the pool. Control animals were trained with these four visual landmarks only. But for animals in the overshadowing groups, an auditory component, X, was added to Landmark D. Test trials, given at the end of training, consisted of placing the rat in the pool with no platform present and recording the time rats spent in the platform quadrant. In Experiment 1, the overshadowing group spent less time in the platform quadrant than controls when tested with D, but the two groups performed equally well on test trials that did not use D. We conclude that the auditory Component X overshadowed the visual Landmark D. In Experiment 2, we obtained evidence of reciprocal overshadowing, of D by X and of X by D. The results of Experiment 3 suggested that an appeal to generalization decrement might not be sufficient to explain these overshadowing effects. 相似文献
16.
In two experiments, two groups of rats were trained in a navigation task according to either a continuous or a partial schedule
of reinforcement. In Experiment 1, animals that were given continuous reinforcement extinguished the spatial response of approaching
the goal location more readily than animals given partial reinforcement—a partial reinforcement extinction effect. In Experiment
2, after partially or continuously reinforced training, animals were trained in a new task that made use of the same reinforcer
according to a continuous reinforcement schedule. Animals initially given partial reinforcement performed better in the novel
task than did rats initially given continuous reinforcement. These results replicate, in the spatial domain, well-known partial
reinforcement phenomena typically observed in the context of Pavlovian and instrumental conditioning, suggesting that similar
principles govern spatial and associative learning. The results reported support the notion that salience modulation processes
play a key role in determining partial reinforcement effects. 相似文献
17.
In two predictive-learning experiments, we investigated the role of the informational value of contexts for the formation of context-specific extinction learning. The contexts were each composed of two elements from two dimensions, A and B. In Phase 1 of each experiment, participants received acquisition training with a target cue Z in context A1B1 (the numbers assign particular values on the context dimensions). In Phase 2, participants were trained with conditional discriminations between two other cues, X and Y, for which only one of the two context dimensions was relevant. In a third phase, participants received extinction trials with cue Z in context A2B2. During a final test phase, we observed that a partial change of the extinction context disrupted extinction performance when the extinction context was changed on the dimension that had been trained as being relevant for the conditional discrimination. However, when the extinction context was changed on the irrelevant context dimension, extinction performance was not affected. Our results are consistent with the idea that relevant contexts receive more attention than do irrelevant contexts, leading to stronger context-specific processing of information learned in the former than in the latter type of contexts. 相似文献
18.
In two pairs of three-stage conditioned taste aversion experiments, we examined the effects of delay interval (1 or 21 days)
between the second and third stages, and of context in which the animals spent the delay (same as or different from the context
of the other stages) on latent inhibition (LI) and spontaneous recovery following extinction. In the LI experiments (Experiments
1A and 1B), the first stage comprised nonreinforced presentations to saccharin or to water. In the second stage, rats were
conditioned by saccharin paired with LiCl. In the extinction experiments (Experiments 2A and 2B), the order of the stages
was reversed. For all experiments, Stage 3, the test stage, consisted of three presentations of saccharin alone. There was
a super-LI effect in the saccharin-preexposed group that spent the 21- day delay in the different context (Experiment 1A).
When the delay was spent in the same context, there was no difference in the amount of LI between the short- and long-delay
groups (Experiment 1B). Conversely, there was a spontaneous recovery effect in the long-delay/same-context group (Experiment
2B), but not in the long-delay/different-context group (Experiment 2A). The pattern of results, incompatible with current
explanations of delay-induced changes in memory performance, was interpreted in terms of an interaction between the delay
conditions (same or different delay context), which modulate the extinction of previously acquired context-CS-nothing associations
(during CS-alone presentations), and primacy effects. 相似文献
19.
Four experiments used a within-subjects design with rats to study the effects of preexposure on the restoration of fear responses
(freezing) to an extinguished conditioned stimulus (CS). In each experiment, rats were preexposed to one CS (A), but not to
another (B), and then were exposed to pairings of each of these CSs with an aversive unconditioned stimulus (US). In each
experiment, there was less freezing to A than to B across extinction, showing a latent inhibitory effect of preexposure. There
was no differential recovery to A and B following either a US reexposure (Experiment 1) or a delay interval (Experiment 2). However, when a delay interval included US reexposure, there was greater recovery to the preexposed CS, A, than to the
nonpreexposed CS, B (Experiments 1, 3, and 4). These results suggest that the effects of US reexposure and delay combine to affect recovery from the depressive effects
of CS-alone exposure. The results are consistent with the view that US reexposure produces better mediated conditioning of
CSs that are strongly associated with the context. The results may additionally reflect an effect of preexposure on the learning
produced by extinction. 相似文献
20.
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