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1.
Experiment 1 sought to determine whether schedule-induced drinking could be abolished by means of a taste aversion. Polydipsic rats were given access to a .4% saccharin solution while they were exposed to an intermittent food schedule. Immediately after the session, they received an intraperitoneal injection of either lithium chloride or sodium chloride. Following a recovery day with water in the experimental chamber, the animals were again exposed to the saccharin solution. The poisoned animals (lithium chloride) drank very little saccharin compared to the control animals (sodium chloride), indicating that they had learned a taste aversion in only one conditioning trial. Experiment 2 established that polydipsic rats can learn a taste aversion despite a long delay between schedule-induced saccharin consumption and poisoning, and that the delay gradient displayed by polydipsic rats is similar to that observed in thirst-motivated rats. 相似文献
2.
The relationship between absolute and relative stimulus novelty was examined within the context of the conditioned taste aversion paradigm in which the relative novelty of the conditioned interoceptive stimulus was manipulated by differential exteroceptive context habituation. Rats received similar isolation histories but either 5 or 30 days of habituation to the test environment prior to treatment. One group was administered lithium chloride following saccharin consumption, a second group was administered isotonic saline following saccharin consumption, and a third group was administered saline after water consumption. The animals habituated for 30 days exhibited greater conditioned avoidance and greater neophobic avoidance of saccharin than did animals habituated for only 5 days. The results are interpreted in terms of a cross-modality stimulus contrast effect which implicates context habituation as an important parameter of both taste neophobia and taste aversion learning. 相似文献
3.
Two experiments with rat subjects examined whether a saccharin taste could potentiate the conditioning of an aversion to a salty taste when the two stimuli were presented together prior to lithium-induced illness. In Experiment 1, a 0.1% (w/v) saccharin solution potentiated conditioning of a very dilute (0.03%) NaCl solution, but had no demonstrable effect on two stronger NaCl solutions (0.6% and 1.2%). In Experiment 2, the 0.1% saccharin solution again potentiated the 0.03% NaCl target, but weaker and stronger saccharin concentrations (0.033% and 0.3%) did not. The ability of a taste to potentiate a secondtaste is not consistent with theories that assume that potentiation is unique to compounds composed of tastes and other, functionally different, nontaste cues. Potentiation may occur when the target stimulus is weakly conditionable on its own and when the particular combination of target and potentiator facilitates perceptual integration of the compound. 相似文献
4.
Michael Domjan 《Learning & behavior》1975,3(3):205-211
Rats repeatedly injected with lithium chloride were subsequently tested drinking novel and familiar solutions of both casein hydrolysate and vinegar. Injections in the absence of edibles result in only a small, and sometimes not reliable, increased avoidance of the novel casein and vinegar solutions. In contrast, if subjects acquired an aversion to saccharin as a result of the lithium injections, this learned aversion generalized to casein hydrolysate, with the generalization greatly enhanced by novelty of the casein flavor. However, the saccharin aversions did not generalize to the novel vinegar solution nearly as much as to the novel casein flavor. These results suggest that previous observations of poison-induced neophobia were probably in part a result of the stimulus generalization of conditioned taste aversions and that in addition to test stimulus novelty some other factor, such as stimulus salience or similarity to the conditioned aversive flavor, is also involved in the generalization of learned taste aversions. 相似文献
5.
Morphine failed to condition a salt taste aversion at a dose (15 mg/kg) sufficient to produce a robust aversion to a saccharin taste. Indeed, three different concentrations of salt (1%, 1.5%, and 2%) paired with the same morphine dose yielded no direct evidence for conditioned aversion. Yet, when a novel saccharin taste was paired in compound with the previously conditioned salt conditioned stimulus, we found evidence for a conditioning to the saccharin cue alone in three separate experiments. Control groups eliminated alternative accounts such as neophobia and differential exposure to morphine. Combined, these findings indicate that morphine conditioned a salt aversion. Although this aversion was not directly expressed, a second-order conditioning procedure was able to provide a more sensitive index of conditioning. 相似文献
6.
Adult male rats were allowed to drink a novel solution of sodium saccharin which was followed .5, 1.5, 4.5, 7.0, 13.5, or 24.0 h later by intubation of a .9, 2.7, 8.1, or 12.15% (w/v) solution of sodium chloride (NaCl). Three days after the single training trial, consumption of saccharin was again measured. Significant differences between groups were found. When consumption by the experimental groups at each CS-UCS delay was compared with that of the isotonic NaCl (.9%) control group, it was found that all groups showed aversions at delays of .5, 1.5, and 4.5 h. Animals intubated with 8.1% or 12.15% NaCl solution also showed aversions at a delay of 7.0 h, and those intubated with the 12.15% solution showed an aversion at a delay of 13.5 h. No NaCl concentration used produced aversions at a CS-UCS interval of 24.0. These results reflect differences in the effectiveness of a range of NaCl concentrations in producing one-trial aversions at long CS-UCS intervals. 相似文献
7.
Three experiments were conducted to determine the effectiveness of intravenous (IV) flavor injections in the formation of conditioned taste aversions and in the attenuation of neophobia. In Experiment 1, two groups of rats were permitted to drink either a .1% saccharin solution or tap water followed immediately by IV injections of lithium chloride (LiCl), and two more groups were given IV injections of a 2% saccharin solution followed immediately by IV injections of either LiCl or distilled water. Injected flavor did not serve as an effective CS for the conditioning of an aversion to .1% saccharin. The second experiment employed a two-bottle procedure to detect attenuation of neophobia using the injected-flavor technique. It was found that, whether saccharin had been injected intravenously (2%), injected intraperitoneally (2% IP), or orally consumed (.1%), neophobia for .5% saccharin was attenuated equally relative to controls. CS-US intervals were manipulated in the final experiment such that IP injections of 2% saccharin solution were followed 0–480 min later by IP injections of LiCl. In this case, it was shown that injected flavor (2% saccharin) could act as an effective CS if the US was delayed (optimally about 120 min) and when the test solution was .1% saccharin. The delay gradient found in Experiment 3 was interpreted as a generalization gradient where optimum conditioning was displayed at the point where the concentration of saccharin circulating in the animal at the time of illness onset most closely matched the concentration of the test solution. 相似文献
8.
Fred J. Boland 《Learning & behavior》1973,1(1):3-4
Seven experimental groups of seven rats each were allowed to consume saccharin solution at different times relative to intubation of lithium chloride solution. Six backward conditioning (BWD) groups were intubed 0.5, 1, 2, 3, 4, and 8 h before saccharin consumption, and a forward conditioning (FWD) group was intubed 0.5 h after saccharin consumption. A no-lithium control group of 14 rats received no intubation. Only the 0.5-h FWD and the 0.5-h BWD groups showed an aversion to saccharin relative to the no-lithium controls. The aversion to saccharin in the 0.5-h FWD group was more pronounced than that in the 0.5-h BWD group. This shows that the aversive effects of lithium toxicosis dissipate far sooner than the aversive effects of X-irradiation. 相似文献
9.
In six experiments, we examined taste and compound taste/taste aversions at different retention intervals. In Experiment 1, saccharin aversions were significantly weaker 1 day after conditioning than 21 days after conditioning. This effect was determined not to be caused by the aftereffects of illness or differential hydration. With the use of a saccharin/denatonium compound, Experiment 2 demonstrated overshadowing of a denatonium aversion at 21- and 1-day retention intervals, Experiment 4 showed a potentiated saccharin aversion only at the 21-day retention interval, and both Experiments 2 and 4 revealed that the aversion of the taste-only controls was stronger at the later retention interval. Experiments 3 and 5 demonstrated that the differences at the two retention intervals were not caused by unconditioned changes in taste preference. Finally, Experiment 6 showed that extinction of the conditioning environment prior to testing results in stronger saccharin aversions than occur in nonextinguished controls. Collectively, these experiments suggest that testing within a 24-h period after conditioning will result in significantly weaker taste aversions. Also, these results support a retrieval-competition explanation that may account for the weakened aversions at the 1-day testing interval of both groups conditioned to single elements and those conditioned to compounds. 相似文献
10.
Eric W. Holman 《Learning & behavior》1976,4(3):329-332
In Experiment I, rats received eight habituation injections of either lithium chloride (LiCl) or sodium chloride (NaCl), then two aversion training trials in which access to saccharin solution was followed by LiCl injections, and finally eight extinction trials with saccharin but no injections. The rats habituated to LiCl showed less aversion to saccharin during training and extinction. In Experiment II, rats received two aversion training trials, then eight habituation trials to either LiCl or NaCl, then eight extinction trials, four more aversion training trials, and eight more extinction trials. The rats habituated to LiCl did not differ during the first extinction period from those habituated to NaCl, but showed less aversion to saccharin during the second training and extinction periods. Consequently, habituation to LiCl reduces the learning of an aversion to saccharin but does not reduce the performance of a previously learned aversion. 相似文献
11.
The importance of ingestive contexts (feeding and drinking) and deprivation states to rats’ transfer of a taste aversion were examined, In Experiments 1 and 2, rats were trained with novel saccharin-treated foods while either food deprived or food and water deprived, They were then tested with a 1,0% saccharin solution while either water deprived or food and water deprived, Comparable aversions to the solution were displayed regardless of deprivation states, Two further experiments examined transfer to a .1% saccharin solution in conjunction with deprivation state change, When both stimulus properties and deprivation were widely discrepant from training to test, reduced transfer was noted. The results suggest that stimulus similarity was a stronger controlling variable than deprivation state similarity in facilitating the transfer of an aversion from a feeding context to a drinking context, The results were viewed as being consistent with the known parameters affecting generalization gradients. 相似文献
12.
On four occasions, Holtzman rats drank saccharin in a distinctive environment prior to lithium-induced toxicosis. Preconditioning exposure to saccharin either in the home cage or in the distinctive environment interfered significantly with the establishment of an environmental aversion. Animals preexposed to the experimental environment, however, showed environmental aversions substantially stronger than those in animals preexposed to saccharin and only slightly higher than those with no preexposure to either the taste or the environment. Subsequent saccharin tests revealed significantly stronger aversions in the group that received environmental preexposure than in any of the other groups. This pattern of outcomes demonstrates taste-mediated potentiation of novel and familiar environmental stimuli as well as overshadowing of the taste by novel environmental stimuli. Furthermore, it indicates that previous demonstrations of taste-mediated environmental potentiation involve facilitated conditioning of the environmental stimuli and decremented conditioning of the taste stimuli. 相似文献
13.
Rick A. Bevins Heather C. Jensen Todd S. Hinze Joyce Besheer 《Learning & behavior》1999,27(3):358-366
Rats (Rattus norvegicus) that received a taste cue (saccharin, saline, quinine, or sucrose) paired with a lithium chloride (LiCl) injection displayed
a robust decrease in consumption of that taste, relative to controls that had the taste unpaired with LiCl. Consumption of
the paired taste increased with each nonreinforced presentation (i.e., extinction). After asymptotic extinction, rats that
had had a 0.1% saccharin cue paired with LiCl consumed less of the saccharin solution than did controls. A similar data pattern
was observed with a 10% sucrose solution. These results are consistent with the view that some aspect of the excitatory CS-US
association remains after extinction. On the other hand, rats that had a bitter (0.005% or 0.001% quinine) or salty (1% or
0.5% saline) solution paired with LiCl drank similar amounts of the fluid as controls after asymptotic extinction treatment.
Together, these experiments suggest that a taste that is either sweet or preferred is required in order to demonstrate the
chronic decrease in fluid consumption after extinction treatment. The data suggest that the conditioning experience prevents
the later development of a preference for the sweet taste, rather than there being a retained aversion that suppresses fluid
consumption. 相似文献
14.
Alexander F. Luongo 《Learning & behavior》1976,4(3):225-230
In three experiments, rats were presented compound solutions consisting of a common element, saccharin, mixed with one of two different flavor elements, cinnamon and wintergreen. Rats in the experimental groups consistently received a toxicosis-inducing injection following one compound solution but not following the other compound solution. Rats in the control groups received toxicosis-inducing injections half the time following each of the compound solutions. After training in each experiment, there were tests for conditioning to the saccharin alone. The experimental groups drank significantly more than the control groups, indicating that the aversion to the partially reinforced saccharin in isolation was less when the different flavor cues were more highly correlated with reinforcement. In Experiment III, there was also a test for conditioning to the cinnamon or wintergreen flavor alone. The experimental group drank significantly less of the continuously reinforced flavor than the control group did of the partially reinforced flavor. These results are similar to those reported within more traditional conditioning paradigms. 相似文献
15.
Andrés Molero-Chamizo 《Learning & behavior》2017,45(2):157-163
Latent inhibition of conditioned taste aversion (CTA) is sensitive to changes in the temporal context. A change in the time of day of conditioning with respect to the time of day of the preexposure can disrupt the latent inhibition. This contextual change in the time of day may reveal a temporal specificity of latent inhibition. The optimum procedure to induce this temporal specificity is not well established. For example, it has been shown that a long period of habituation to temporal contexts is one factor that can determine the effect. However, the experimental conditions on the conditioning day that facilitate this phenomenon are unknown. The aim of this study is to elucidate whether a restriction in the intake of the conditioned taste stimulus affects the temporal specificity of latent inhibition. Two main groups of Wistar rats were tested in a latent inhibition of CTA paradigm, in which the temporal specificity of this phenomenon was analyzed by a change in the time of day of conditioning. The intake of the taste stimulus was restricted in the conditioning day in one of the groups, but this restriction was not applied in the other group. The results indicated temporal specificity of latent inhibition only in the group without restriction, but not in the group with limitation in the intake of the taste stimulus during conditioning. These findings can help to elucidate the characteristics of the procedure to induce temporal specificity of latent inhibition. 相似文献
16.
Joseph V. Lambert Rose Mary Barber Phyllis Carpenito Marilyn Cianfrani Bernadette Mendez Linda C. Potosnak 《Learning & behavior》1989,17(4):457-467
In three experiments, we investigated the existence of conditioned inhibition of body rotation-induced taste aversion. Rats were given conditioned inhibition training in which the taste of saccharin was always followed by rotations, but the taste of vanilla was not. Flavor-preference tests, retardation-of-acquisition tests, and summation tests of inhibition indicated that the vanilla stimulus had acquired conditioned inhibitory properties. These findings could not be interpreted as functions of either initial solution preferences or simple nonassociative effects of flavor preexposure. They lend support to a theory that views learning mechanisms as being central to the phenomenon of motion sickness, and suggest that inhibitors might be effectively employed to ameliorate its symptoms. 相似文献
17.
Experiment I demonstrated that the strength of a rat’s aversion to saccharin is a direct function of the amount of saccharin it consumed prior to poisoning. Using Kalat and Rozin’s (1973) procedure, Experiment II showed that results consistent with a “learned-safety” theory of taste aversion appear to depend on whether rats drink most saccharin on their first or second exposure to the solution prior to poisoning. Experiment III demonstrated that when animals drank equal amounts of saccharin solution on each of two exposures prior to poisoning, evidence strongly confirming the “learned-safety” theory was obtained. These experiments together demonstrate the importance of amount of solution drunk in the determination of taste aversion. 相似文献
18.
Mark E. Bouton 《Learning & behavior》1982,10(2):233-241
Three experiments with rat subjects were designed to investigate the possibility that an extinguished saccharin aversion might be reinstated if the animals are made ill with lithium chloride (in the absence of saccharin) following extinction. Although reinstatement can be obtained when the unconditioned stimulus is presented following the extinction of other kinds of conditioned behaviors, the present experiments provided no evidence that an extinguished taste aversion can be reinstated. No reinstatement was observed, even when the aversion had been only partially extinguished and when multiple injections of lithium chloride were administered in an attempt to reinstate the aversion. 相似文献
19.
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
20.
Water-deprived rats were given a single exposure to saccharin and LiCl, either paired or unpaired. Half the subjects then received three saccharin-only exposures (extinction) in the training enclosure, followed by a single LiCl-only presentation (unconditioned stimulus reinstatement) 8 days after conditioning. The remaining subjects received six saccharin-only exposures, followed by LiCl reinstatement 13 days after conditioning. In both cases LiCl reinstatement occurred outside the training/test context. Appreciable recovery from extinction was observed after the partial loss of taste aversion obtained with three extinction sessions and the 8-day conditioning-reinstatement interval, but not after the asymptotic loss of taste aversion obtained with six extinction sessions and the 13-day conditioning-reinstatement interval. Conditioned taste aversions appear to be similar to more traditional associations with respect to both extinction and reinstatement-induced recovery from extinction. The results are discussed with reference to the event-memory, contextual-conditioning, and facilitated-retrieval hypotheses of postextinction reinstatement effects. 相似文献