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1.
Two lick suppression experiments using rats were conducted to determine whether extinction of a punctate excitor in a particular
context would result in that context becoming a conditioned inhibitor, as defined by passing both summation and retardation
tests. The role of extinction trial spacing was investigated as a possible determinant of whether the extinction context would
become inhibitory. Experiment 1 demonstrated that, although inhibition was evident using either massed or spaced extinction trials, spaced trials reduced
measurable inhibition as assessed by the summation test, but trial spacing had no influence on retardation test performance.
Experiment 2 confirmed Experiment 1’s conclusions while controlling for the influence of latent inhibition on the retardation test. In Experiment 2, the context proved inhibitory only following massed extinction trials. These data suggest that, at least with select parameters,
an extinction context can become inhibitory. 相似文献
2.
In five conditioned taste aversion experiments with rats, summation, retardation, and preference tests were used to assess the effects of extinguishing a conditioned saccharin aversion for three or nine trials. In Experiment 1, a summation test showed that saccharin aversion extinguished over nine trials reduced the aversion to a merely conditioned flavor (vinegar), whereas three saccharin extinction trials did not subsequently influence the vinegar aversion. Experiment 2 clarified that result, with unpaired controls equated on flavor exposure prior to testing; the results with those controls suggested that the flavor extinguished for nine trials produced generalization decrement during testing. In Experiment 3, the saccharin aversion reconditioned slowly after nine extinction trials, but not after three. Those results suggested the development of latent inhibition after more than three extinction trials. Preference tests comparing saccharin consumption with a concurrently available fluid (water in Experiment 4, saline in Experiment 5) showed that the preference for saccharin was greater after nine extinction trials than after three. However, saccharin preference after nine extinction trials was not greater, as compared with that for either latent inhibition controls (Experiments 4 and 5) or a control given equated exposures to saccharin and trained to drink saline at a high rate prior to testing (Experiment 5). Concerns about whether conditioned inhibition has been demonstrated in any flavor aversion procedure are discussed. Our findings help explain both successes and failures in demonstrating postextinction conditioned response recovery effects reported in the conditioned taste aversion literature, and they can be explained using a memory interference account. 相似文献
3.
Gonzalo Miguez Bridget McConnell Cody W. Polack Ralph R. Miller 《Learning & behavior》2018,46(3):265-280
This report is part of a larger project examining associative interference as a function of the nature of the interfering and target associations. Lick suppression experiments with rats assessed the effects of context shifts on proactive outcome interference by latent inhibition (LI) and Pavlovian conditioned inhibition (CI) treatments on subsequently trained Pavlovian conditioned excitation treatment. LI and CI were trained in Context A during Phase 1, and then excitation treatment was administered in Context B during Phase 2, followed by tests for conditioned excitation in Contexts A, B, or C. Experiment 1 preliminarily established our LI and CI treatments and resulted in equally retarded acquisition of behavioral control when the target cue was subsequently trained as a conditioned excitor and tested in Context A. However, only CI treatment caused the target to pass a summation test for inhibition. Centrally, Experiment 2 consisted of LI and CI treatments in Context A followed by excitatory training in Context B. Testing found low excitatory control by both LI and CI cues in Context A relative to strong excitatory control in Context B, but CI treatment transferred to Context C more strongly than LI treatment. Experiment 3 determined that LI treatment failed to transfer to Context C even when the number of LI trials was greatly increased. Thus, first-learned LI appears to be relatively context specific, whereas first-learned CI generalizes to a neutral context. These observations add to existing evidence that LI and CI treatments result in different types of learning that diverge sharply in transfer to a novel test context. 相似文献
4.
In four experiments utilizing an appetitive conditioning preparation, reacquisition of conditioned responding was found to occur both rapidly and slowly following extinction. In Experiment 1, acquisition of responding to a tone that had been conditioned and extinguished occurred more rapidly than acquisition in either a group that received equivalent exposure to the food unconditioned stimulus or a “rest” control group that received only exposure to the apparatus in the first two phases. However, reacquisition was impaired relative to acquisition in a “learning-experienced” group that had previously received conditioning and extinction with a different stimulus. Experiments 2 and 3 produced similar results, but also found that high responding during reacquisition was confined to trials that followed reinforced, rather than nonreinforced, trials. Experiment 4, in which very few initial conditioning trials were used, produced reacquisition that was slow compared with both learning-experienced and rest controls. The results are consistent with a role for sequential learning: Reacquisition is rapid when animals have learned that reinforced trials signal other reinforced trials. 相似文献
5.
Three experiments examined inhibitory learning in rats, using Pavlovian and differential inhibitory eyeblink conditioning
procedures. Experiment 1 was designed to compare summation and retardation effects following Pavlovian conditioned inhibition
(A1/XA) or differential inhibition (A1/X) training using auditory and visual conditioned stimuli (CSs). After ten 100-trial
sessions of training, both Pavlovian conditioned inhibition and differential inhibition produced a retardation effect. However,
a summation effect was obtained only for rats given Pavlovian conditioned inhibition training. Experiment 2 showed that increasing
differential inhibition training to twenty 100-trial sessions produced summation and retardation effects. In Experiment 3,
rats were trained with either ten or twenty 100-trial sessions of intramodal inhibitory training with two tone CSs (2 kHz
vs. 8 kHz). Summation and retardation effects were obtained after only 20 sessions of differential conditioning. The findings
indicate that extensive training is needed to establish conditioned inhibition with intermodal or intramodal differential
conditioning. 相似文献
6.
Pavlov (1927/1960) reported that following the conditioning of several stimuli, extinction of one conditioned stimulus (CS) attenuated responding
to others that had not undergone direct extinction. However, this secondary extinction effect has not been widely replicated in the contemporary literature. In three conditioned suppression experiments with rats,
we further explored the phenomenon. In Experiment 1, we asked whether secondary extinction is more likely to occur with target
CSs that have themselves undergone some prior extinction. A robust secondary extinction effect was obtained with a nonextinguished
target CS. Experiment 2 showed that extinction of one CS was sufficient to reduce renewal of a second CS when it was tested
in a neutral (nonextinction) context. In Experiment 3, secondary extinction was observed in groups that initially received
intermixed conditioning trials with the target and nontarget CSs, but not in groups that received conditioning of the two
CSs in separate sessions. The results are consistent with the hypothesis that CSs must be associated with a common temporal
context during conditioning for secondary extinction to occur. 相似文献
7.
Kelly J. Stanhope 《Learning & behavior》1989,17(3):311-321
A dissociation between the effect of reinforcer type and response strength on the force of the pigeon’s keypeck response was shown in three experiments. In Experiment 1, pigeons were trained to peck two conditioned stimuli, one paired with water and another paired with grain. The pigeons made more forceful pecks for grain than for water and also showed a tendency, albeit an unreliable one, to respond on a higher percentage of food trials than water trials. In Experiment 2, the pigeons from Experiment 1 were satiated with either food or water and were then presented with the two conditioned stimuli in an extinction test. It was found that, regardless of the drive state, the pigeons made more forceful pecks to the stimulus that predicted food than to the stimulus that predicted water. In the thirsty group, however, this difference in force was not accompanied by a difference in the percentage of trials with a response. In Experiment 3, pigeons trained with a single reinforcer pecked more often on instrumentally reinforced trials than on Pavlovian conditioning trials, but there was no difference in the force of the pecks. Taken together, these results imply that differences in response strength cannot account for the difference between the force of food- and water-reinforced pecks. Instead, stimulus-substitution theory may provide the best account of the topography of the two types of pecks. 相似文献
8.
Two experiments were performed using rats in a conditioned suppression procedure to test two different methods for extinguishing Pavlovian conditioned inhibition. In both experiments, a target stimulus, X, was made inhibitory by giving discrimination training of the form A+ AX?. Then, in Experiment 1, an attempt was made to extinguish the inhibition conditioned to X by presenting nonreinforced occurrences of X, of AX, and of A. Testing for conditioned inhibition took the form B+ BX?. It was found that the extinction procedure did not weaken the inhibitory properties of X. Experiment 2 attempted to extinguish the inhibition conditioned to X by presenting X randomly and independently of the reinforcer, electric grid shock. This procedure appeared to weaken inhibition quickly and permanently. 相似文献
9.
Extinction-induced attenuation of single-phase and two-phase blocking was examined with rats in a conditioned lick-suppression
task. In Experiment 1, which compared the effectiveness of single- and two-phase blocking, it was found that single-phase
blocking was facilitated by the initiation of training with an A-US trial rather than an AX-US trial. Single-phase (but not
two-phase) blocking was attenuated as a result of 200 extinction trials with the blocking stimulus (Experiment 2). Experiment
3 revealed recovery from two-phase blocking after 800 extinction trials with the blocking stimulus. Recovery from both types
of blocking was specific to the blocked CS trained in compound with the extinguished stimulus (Experiment 4). This is the
first article to report that the blocking deficit can be reversed by extinguishing the blocking stimulus. These results are
discussed in light of acquisition models (i.e., retrospective revaluation) and expression models (i.e., the comparator hypothesis). 相似文献
10.
Three conditioned suppression experiments with rats as subjects investigated the influence of higher order associations in determining the response potential of a target stimulus. In these experiments, a Pavlovian conditioned inhibitor was compounded with the target cue during extinction treatment. In Experiment 1, strong suppression was observed to the target cue that was given extinction treatment in the presence of a conditioned inhibitor, relative to a target that was extinguished with an associatively neutral cue or was extinguished alone, suggestive of enhanced protection from extinction provided by a conditioned inhibitor. This effect was replicated in a sensory preconditioning preparation in Experiment 2; in Experiment 3, in a sensory preconditioning preparation, this protection effect was retroactively attenuated when the conditioned excitor used to train the conditioned inhibitor was extinguished following extinction of the target. This provides evidence that, at least in a sensory preconditioning preparation, stimuli that are only indirectly associated with the target cue can contribute to the response potential of that target. 相似文献
11.
Christopher L. Cunningham 《Learning & behavior》1979,7(1):45-52
A conditioned-emotional-response (CER) paradigm was used in two experiments to evaluate the effects of alcohol on extinction. In both experiments, rats received tone-shock pairings without alcohol and then received extinction trials either with or without alcohol (injections of saline, .75 or 1.5 g/kg ethanol). The high dose of alcohol suppressed baseline barpressing for food reward, but there was only weak evidence (Experiment 2) that it enhanced responding during the tone early in extinction. In both experiments, extinction of CER under the high alcohol dose was found to be state dependent, that is, post-extinction tests after saline injection showed a reinstatement of suppression to the tone. Experiment 2 indicated that this effect could be attributed to alcohol’s becoming a conditioned inhibitory stimulus as a result of its association with extinction. This supports the general suggestion that situational stimuli normally become inhibitory during the course of simple extinction and may have implications for the role that state-dependent learning plays in drug dependence. 相似文献
12.
In two experiments, resistance to satiation was compared with resistance to extinction. In Experiment 1, rats given initial trials in a straight-alley runway while satiated failed to show increased resistance to satiation in a later test phase. This negative finding contrasts with the increased resistance to extinction usually found following initial nonrewarded trials in a straight alley. In Experiment 2, rats were extinguished or were run while satiated following deprived acquisition, and then were either shifted to the other condition or maintained under the same condition. A greater response decrement was produced by extinction than by satiation, both when current performance was examined and when the persistent effect of satiation or extinction on later performance was examined. These results show that there are important dissimilarities in the effects of satiation and extinction, dissimilarities that suggest that extinction is more nonrewarding or aversive than satiation. It seems likely that extinction involves processes (such as frustration, arousal of aversive motivation, and conditioned inhibition) not involved in satiation, which account for the greater response decrement in extinction as compared with satiation. 相似文献
13.
Extinction of a conditioned palatability shift preceded extinction of conditioned taste avoidance whether rats were tested
using a within-subjects design or a between-subjects design. In each of two experiments, consumption of 0.1% saccharin was
paired with either 20 ml/kg of 0.15 M LiCl or equivolume physiological saline on a single trial. In Experiment 1, on each
of 10 extinction trials, rats were given a taste reactivity test immediately prior to a consumption test. In Experiment 2,
half of the rats were extinguished by taste reactivity testing and half of the rats were extinguished by a consumption test
on each of 10 extinction trials. In both experiments, the aversive reactions of gaping and passive dripping were extinguished
in a single trial and the suppression of ingestive reactions was extinguished in 2 trials; however, extinction of taste avoidance
required 4–5 trials. These results suggest that rats continue to avoid a lithium-paired flavor even when they do not have
an aversion to the taste. 相似文献
14.
Rats were used in a conditioned-suppression paradigm to determine whether an extinction treatment would enhance a moderately developed conditioned inhibitor (CS?). To dissipate unconditioned suppression to the training stimuli, the subjects were first habituated to the stimuli and then given Pavlovian conditioned-inhibition (CI) training involving reinforced presentations of a clicker and nonreinforced compound presentations of that stimulus and the intended CS?, either a light or a tone. Thereafter, experimental subjects received presentations of their CS? by itself, whereas controls received no further training. Following the occurrence and loss of conditioned suppression to the CS? in the extinction phase, summation and retardation tests showed enhanced CI for the experimental subjects relative to both the controls and their own earlier levels of inhibitory performance. In fact, the enhanced inhibition for the experimental subjects approximated that shown by a comparison group for which the CS? had been strongly developed as an inhibitor. These findings suggest that an excitatory representation is associated with the CS? early in CI training, and that subsequent presentations of the CS? by itself strengthen its inhibitory effect by allowing it to be nonreinforced in the presence of that representation. 相似文献
15.
In Experiment 1, pigeons were trained to peck red or blue keys for food reinforcement at variable intervals, while food was contingent on withholding key pecks in the presence of a vertical line (omission training). When the line was briefly superimposed on red or blue in a compound test, responding was reduced. When the orientation of the line was varied during extinction, generalization gradients were variable but often had most responding at or near vertical. In Experiment 2, pigeons were trained in a discrete trials procedure that made food contingent upon pecking in the presence of triangle, and upon the absence of pecking in the presence of red (omission training). Food was never given on green-key trials (extinction). When red or green backgrounds were presented with the triangle in a compound test, responding was reduced similarly in the presence of both key colors. Subsequent resistance to auto-shaping was also similar for red and green. These data, taken together with reports in the literature, suggest that the inhibitory effects of omission training are quite similar to those of extinction. Thus, the crucial condition for obtaining inhibitory effects is not a negative stimulus-reinforcer correlation, as in extinction, but simply the establishment of low rates of responding to the inhibitory stimulus. 相似文献
16.
Carlo Ambrogi Lorenzini Corrado Bucherelli Aldo Giachetti Giovanna Tassoni 《Learning & behavior》1990,18(2):191-198
The effect of tail-handling on exploratory behavior of the rat, measured as step-through latency in a well-lighted, two-box apparatus, was investigated. Male adult Wistar rats, aged 60 days, were employed in all three experiments. Experiment 1, in which the subjects were handled at different times after entering the goal chamber (0, 10, 30, 60, 300, and 600 sec), showed that immediate handling, relative to detention in the goal chamber (delay of handling) had an inhibitory effect on exploration. Experiment 2 showed that groups handled immediately after entering the goal chamber but then detained there for different durations all showed the same progressive inhibition of exploration. Experiment 3 showed that the inhibition of exploration (very long step-through latencies) due to tail-handling immediately after entering the goal chamber could be significantly decreased by further trials in which handling was delayed for a sufficient duration (30 sec or more). Handling is discussed as a stimulus that is aversive enough to elicit conditioned passive-avoidance responses (inhibition of exploratory behavior), although it is subject to rapid extinction. 相似文献
17.
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
18.
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
19.
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
20.
Discrimination performance was investigated with pigeons using feature negative (FN) discrimination procedures which differed in the temporal arrangement of the stimuli on S? trials. In both procedures, a single common element was presented on reinforced (S+) trials. In thesimultaneous FN procedure, a distinguishing element was presented simultaneously with the common element of S? trials. In thesequential FN procedure, the distinguishing element preceded onset of the common element on S? trials. In two experiments, the sequential FN procedure yielded better discrimination performance. In Experiment 1, a summation test designed to separate learning and performance variables indicated that sequential FN subjects had learned the negative relationship between the distinguishing element and reinforcement while simultaneous FN subjects had not. In Experiment 2, summation and acquisition tests indicated that the distinguishing element developed inhibitory properties in the sequential FN procedure but not in the simultaneous FN procedure. 相似文献