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1.
We compared the rate of acquisition and strength of retention of conditioned context aversion (CCA) with conditioned taste aversion (CTA) using pigmented, genetically heterogeneous mice (derived from Large and Small strains). Extending previous findings, in Experiment 1, mice accustomed to drinking from large glass bottles in the colony room learned to avoid graduated tubes after a single conditioning trial when drinking from these novel tubes was paired with injections of LiCl. The results also showed that CCA could be developed even when there was a 30-minute delay between conditioned stimulus and unconditioned stimulus. Retention of the aversion lasted for 4 weeks in both Immediate and Delay groups. Studies of conditioned saccharin aversion were conducted in Experiment 2. CTA acquisition was very similar to that observed in CCA and duration of aversion retention was similar in the CCA and CTA Delay groups, although at least 2 weeks longer in the Immediate group. Thus, CCA acquisition and retention characteristics are closer to those seen for CTA than has previously been reported. In Experiment 3, we examined whether albino mice (which are known to have weaker visual abilities compared to pigmented mice) would develop CCA comparable to those of pigmented mice. The development of conditioned aversion and its duration of retention was similar in albinos and pigmented mice. Nonspecific aversion emerged as an important contributor to strength of aversion during retention trials in both CCA and CTA paradigms with pigmented (but not albino) mice and deserves additional scrutiny in this field of inquiry. 相似文献
2.
Two experiments examined the effects of nonreinforced flavor exposure on the strength of a conditioned taste aversion. Rats were conditioned by pairing maple flavor with LiC1. Prior to or subsequent to this pairing, some animals received nonreinforced exposure to either maple or saccharin. In separate subjects, preference for maple was tested 1 or 21 days after the last training episode. In the first experiment, the nonreinforced stimulus exposure occurred before conditioning (latent inhibition, or LI, procedure); in the second experiment, the nonreinforced exposure occurred after conditioning (extinction, or EXT, training). In both experiments, nonreinforced exposure to maple or saccharin reduced the magnitude of a conditioned maple aversion when testing occurred soon after conditioning. When testing was delayed, however, the attenuation due to nonreinforced saccharin exposure dissipated, both with the LI procedure and with EXT. In contrast, the nonreinforced exposure to maple was found to attenuate conditioned reactions at both short and long retention intervals. The release from generalized LI and spontaneous recovery following generalized EXT training are discussed in terms of retrieval processing. The possibility that the same mechanism may underlie LI and EXT is considered. 相似文献
3.
In three conditioned taste aversion experiments with rats, latent inhibition (LI) was examined as a function of the time interval (1 or 21 days) between the conditioning and the test phases. In Experiments 1 and 2, the effects of US intensity on LI were examined. LI increased in the 21-day condition, as compared with the 1-day condition, with medium and high US intensity, but not with weak US intensity. Groups not preexposed to the CS flavor had similar aversions when testing was conducted 1 day after conditioning, as compared with 21 days. In Experiment 3A, delay-induced super-LI was obtained when the delay was spent in the home cage and the experimental stages took place in a different context (as in Experiments 1 and 2). In Experiment 3B, when all the stages, including the delay period, were conducted in the home cage, there was no super-LI effect. The modulation of delay-induced super-LI as a function of US intensity and context extinction is discussed in relation to association deficit and retrieval interference theories of LI. 相似文献
4.
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
5.
Todd R. Schachtman Wesley J. Kasprow Robert C. Meyer Mark J. Bourne Julie A. Hart 《Learning & behavior》1992,20(3):207-218
Using a conditioned taste aversion preparation overshadowing of flavor-illness association was produced through the presentation of a second flavor during the interval between the first flavor and illness. The modulatory effects of extinguishing the association between the second (over-shadowing) flavor and illness on conditioned responding to the target flavor was investigated. In Experiment 1, we found that, following one-trial overshadowing, extinction of the overshadowing flavor had no effect on conditioned responding to the target flavor. In Experiment 2, we found a similar absence of an effect of extinction of the overshadowing stimulus in a multitrial over-shadowing paradigm. Experiment 3 confirmed the results of Experiments 1 and 2 using conditioning parameters that were designed to weaken the association between the overshadowed flavor and illness. In Experiments 4 and 5, we used simultaneous presentation of the flavors during conditioning and obtained a weakened aversion to the overshadowed flavor when the overshadowing CS was extinguished. These findings are inconsistent with previous observations in conditioned fear preparations that suggest that extinction of the association between the overshadowing stimulus and the unconditioned stimulus attenuates overshadowing. Possible reasons for the discrepant results are discussed. 相似文献
6.
Two groups of rats each received 5 drops of NaCl solution from a dropper placed directly inside the mouth. The experimental group was then injected with lithium chloride to establish a conditioned taste aversion. The control group was injected 24 h later. After a recovery day the above procedures were repeated. On the next day both groups received 5 drops of a saccharin solution followed immediately by 5 drops of the NaCl solution. Subsequent preference tests established that the experimental group had learned an aversion to the saccharin solution as a result of its pairing with the NaCl solution which had previously been associated with poisoning. These results demonstrate that higher order conditioning of a taste aversion can be established using tastes as both the first-order stimulus and the second-order stimulus. 相似文献
7.
Nonreinforced exposure to a cue tends to attenuate subsequent conditioning with that cue—an effect referred to as latent inhibition (LI). In the two experiments reported here, we examined LI effects in the context of conditioned taste aversion by examining both the amount of consumption and the microstructure of the consummatory behavior (in terms of the mean size of lick clusters). The latter measure can be taken to reflect affective responses to, or the palatability of, the solution being consumed. In both experiments, exposure to a to-be-conditioned flavor prior to pairing the flavor with nausea produced by lithium chloride attenuated both the reduction in consumption and the reduction in lick cluster sizes typically produced by taste aversion learning. In addition, we observed a tendency (especially in the lick cluster measure) for nonreinforced exposure to reduce neophobic responses to the test flavors. Taken together, these results reinforce the suggestion from previous experiments using taste reactivity methods that LI attenuates the effects of taste aversion on both consumption and cue palatability. The present results also support the suggestion that the failure in previous studies to see concurrent LI effects on consumption and palatability was due to a context specificity produced by the oral taste infusion methods required for taste reactivity analyses. Finally, the fact that the pattern of extinction of conditioned changes in consumption and in lick cluster sizes was not affected by preexposure to the cue flavors suggests that LI influenced the quantity but not the quality of conditioned taste aversion. 相似文献
8.
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
9.
Rats were successively exposed to three solutions with distinctively different flavors and then tested for both neophobia and propensity to form conditioned taste aversions to a fourth distinctively flavored solution. All permutations between the four solutions (salty, bitter, sweet, and sour) were examined. The prior exposures resulted in attenuation of neophobia to novel salty and sour solutions, but not to equally novel bitter or sweet solutions. These effects were found to depend upon thediversity of the prior ingestive events rather than upon either a single specific flavor experience or a summation of the reductions in generalized neophobia accrued by each substance separately; both of the latter findings are inconsistent with stimulus generalization being responsible for the observed attenuation of neophobia to salty and sour solutions following exposure to diverse different solutions. A further test of generalization between the salty and bitter solutions, consisting of associating one flavor with poison and extinguishing the avoidance response in half the animals prior to testing for generalization of conditioned taste aversion to the other flavor, also proved negative. Although these effects of exposure to flavors distinctly different from the test solution may be dependent upon solution concentrations, further research found that the same pretest exposures and same test concentrations failed to inhibit formation of conditioned taste aversions. A demonstration of “latent inhibition” attested to the sensitivity of our procedure to potential interference with acquisition of conditioned taste aversions. The results are considered in light of the relationship between neophobia and conditioned tasted aversions, the differential biological relevancy of specific tastes, and abstraction as a cognitive capability of rats. The possibility is raised that the defense against toxins is not the primary function of neophobia. 相似文献
10.
Rats were used in a conditioned taste aversion procedure in order to examine the effects of context exposure duration during
the conditioning sessions on conditioned responding. One flavor was paired with lithium chloride during a long session in
one context, whereas another flavor was conditioned during a short session in another context. Testing occurred in the home
cage. The results showed that conditioning during short sessions produced strong conditioned taste aversions. Conditioning
during long sessions produced strong conditioned taste aversions when the conditioned-stimulus-unconditionedstimulus (CS-US)
pairing occurred at the end of the lengthy session. Other results showed that context-US associations were formed during the
short duration sessions and that these associations supported conditioned responding to the CS trained in that context. The
results are discussed with respect to the different influences that contextual cues can exert on conditioned responding. 相似文献
11.
Latent inhibition, which refers to attenuated responding to a conditioned stimulus (CS) after CS-unconditioned stimulus (CS-US) pairings as a result of CS-alone presentations prior to the pairings, is often attenuated if preexposure and conditioning occur in different contexts (i.e., it is context specific). Here we report two conditioned lick suppression experiments, using rat subjects, that examined whether manipulations known to attenuate the context specificity of extinction could also eliminate the context specificity of latent inhibition. Context specificity of latent inhibition was eliminated when the CS was preexposed in multiple contexts (Experiment 1) and when the CS was massively pre-exposed in the training context alone (Experiment 2). These results and their practical implications are discussed in the framework of contemporary theories of latent inhibition. 相似文献
12.
Mark D. Holder 《Learning & behavior》1988,16(2):231-234
In many publications, Sjödén, Archer, and their colleagues have studied conditioned taste aversions and found that in addition to taste, the bottle and/or spout containing a solution exerts strong control over the expression of an aversion. For example, Sjödén and Archer claim that this bottle stimulus will support a bottle-illness association even with long delays between the bottle and illness and after only a single conditioning trial. They have interpreted their results as indicating that contextual effects are important in taste-aversion learning. However, a confound in their procedure, stemming from the bottles they used, could explain their results in a simple way. Sjödén and Archer have emphasized that the bottle stimuli they used to distinguish between contexts consisted of one of two different sizes of drinking spouts, the larger of which made a clicking noise when licked. However, the larger spouts were always attached to plastic bottles and the smaller spouts were always attached to glass bottles. If discriminable tastes from the plastic bottles existed, then taste may have been inadvertently manipulated. Support for the likelihood of a plastic taste includes the seminal work on taste-aversion learning that stemmed from the serendipitous use of plastic bottles in the cage that rats were irradiated in and glass bottles in the home cages (see Garcia, McGowan, & Green, 1972). In these early demonstrations, rats learned to avoid the taste of water in the plastic bottles but not the taste of water in the glass bottles. 相似文献
13.
Rats were used to examine the extent to which extinction of an acquired conditioned taste aversion retards subsequent reacquisition. A saccharin-flavored solution (sac) was paired with LiCl and then followed by CS-alone extinction trials with this flavor. A control group received a different flavor, decaffeinated-coffee (coff), during initial conditioning and extinction. Sac was then paired with LiCl for all rats during a second conditioning phase. Reacquisition of the aversion to sac was retarded relative to the acquisition of an aversion to sac by the control group. A similar experiment with fewer extinction trials, but still with complete loss of the initial aversion, did not obtain slow reacquisition. The results are discussed with respect to an interference view of extinction and the slow-reacquisition effect. 相似文献
14.
Almond and peppermint extracts were combined with salt and citric acid as cues in conditioned flavor preference conditioning. In Experiment 1, extracts overshadowed tastes, although tastes and extracts conditioned equally well when presented in isolation. In Experiments 2 and 3, tastes and extracts were conditioned in isolation prior to conditioning of a taste/extract compound. The conditioning history of the tastes and extracts did not affect the overshadowing of taste by extract. The results of Experiment 4 showed that rats could learn to discriminate between a taste and extract presented in isolation vs. the taste/extract compound. Thus, extracts do not interfere with sensing the tastes. We suggest that a taste/extract compound produces a configural stimulus that is more characteristic of the extract than the taste. 相似文献
15.
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
16.
In these experiments, we investigated the nature of potentiation in the conditioned flavor preference paradigm. Almond and banana extracts, which have strong odor components, were combined with salt and saccharin (liked tastes; Experiment 1) or quinine and citric acid (disliked tastes; Experiment 2) in a flavor preference procedure that mixed these solutions with a caloric reinforcer (polycose). The results showed that liked tastes potentiated preference conditioning to extracts (Experiment 1), whereas extracts potentiated preference conditioning to disliked tastes (Experiment 2). In both experiments, the presumably less liked stimulus (i.e., the extract in Experiment 1 and the disliked taste in Experiment 2) was the potentiated cue. 相似文献
17.
In two experiments, rats were presented with a taste conditioned stimulus (CS) alone, an odor CS alone, or an odor-taste compound followed by lithium chloride injection. When tested 1 day following conditioning, there was evidence that the odor cue overshadowed conditioning to the taste; however, there was no indication of overshadowing following a longer (21-day) retention interval, despite undiminished strength of the aversion in animals conditioned with only the single element (taste). The overshadowing observed at the 1-day retention interval was not reciprocal. Rats conditioned with the odor CS alone or with the compound CS expressed odor aversions of comparable strength—that is, no overshadowing. However, in contrast to the taste aversion, overshadowing of conditioning to the odor by taste was evident following a 21-day retention interval. Rather than reflecting a failure of the overshadowed stimulus to acquire associative strength, these data suggest that overshadowing may be expressed, or not expressed, as a result of changes in the relative retrievability of learned associations over time. 相似文献
18.
Latent inhibition refers to attenuated responding to a conditioned stimulus (CS) that was repeatedly presented without reinforcement prior
to the CS-unconditioned stimulus (US) pairings. Using water-deprived rats as subjects, we observed that interpolating task-irrelevant
stimulation between the preexposure and conditioning phases of a latent inhibition procedure attenuated latent inhibition
(Experiments 1A, 1B, and 2). Apparently, interpolated stimulation segments the preexposure and conditioning treatments into
two separate experiences, much in the same way that a change of context would. Consistent with this view, the interpolated
stimulation did not disrupt latent inhibition if it was also presented during both preexposure and conditioning (Experiment
3). We view these results as analogous to those of Escobar, Arcediano, and Miller (2003), who suggested that the difficulty
in observing latent inhibition in human adults is related to the segmentation between preexposure and conditioning caused
by the usual interpolation of instructions in preparations with humans. 相似文献
19.
Stimuli associated with primary reinforcement for instrumental behavior are widely believed to acquire the capacity to function as conditioned reinforcers via Pavlovian conditioning. Some Pavlovian conditioning studies suggest that animals learn the important temporal relations between stimuli and integrate such temporal information over separate experiences to form a temporal map. The present experiment examined whether Pavlovian conditioning can establish a positive instrumental conditioned reinforcer through such temporal integration. Two groups of rats received either delay or trace appetitive conditioning in which a neutral stimulus predicted response-independent food deliveries (CS1→US). Both groups then experienced one session of backward second-order conditioning of the training CS1 and a novel CS2 (CS1–CS2 pairing). Finally, the ability of CS2 to function as a conditioned reinforcer for a new instrumental response (leverpressing) was assessed. Consistent with the previous demonstrations of temporal integration in fear conditioning, a CS2 previously trained in a trace-conditioning protocol served as a better instrumental conditioned reinforcer after backward second-order conditioning than did a CS2 previously trained in a delay protocol. These results suggest that an instrumental conditioned reinforcer can be established via temporal integration and raise challenges for existing quantitative accounts of instrumental conditioned reinforcement. 相似文献
20.
Weanling rats were tested for retention of an aversion to a novel flavor (chocolate milk) that had been conditioned as a single-element conditioned stimulus (CS) or in compound with a novel ambient odor (banana). The presence of the ambient odor during conditioning had no effect on flavor aversion shortly thereafter, confirming previous results. The flavor aversion observed 21 days after conditioning, however, was significantly stronger for pups conditioned with the single-element CS than for those given the flavor-odor compound as the CS. This retention effect was due to a surprisingincrease in the conditioned aversion observed 21 days after conditioning with the single-element CS. A second experiment confirmed this paradoxical increase in retention of the aversion to chocolate milk. This experiment also verified that no such increase occurred in retention of the conditioned aversion to a different flavor (saccharin), whether the initial aversion was strong or weak. The results may be explained in terms of generalized latent inhibition from consumption of mother’s milk. 相似文献