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1.
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
2.
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
3.
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
4.
Matías López Patricia Gasalla Mercedes Vega Cheryl L. Limebeer Erin M. Rock Katharine J. Tuerke Holly Bedard Linda A. Parker 《Learning & behavior》2010,38(2):177-186
The present experiments, using the latent inhibition (LI) paradigm, evaluated the effect of nonreinforced exposure to saccharin
on the acquisition of an LiCl-induced saccharin aversion as measured by conditioned disgust reactions in the taste reactivity
test and conditioned taste avoidance in a consumption test. When rats were preexposed to saccharin by bottle exposure (Experiments
1 and 3), LI was evidenced only by conditioned taste avoidance (bottle testing), but not by conditioned disgust reactions
(intraoral [IO] testing). On the other hand, when rats were preexposed to saccharin by IO infusion (Experiments 2 and 3),
LI was evidenced only by conditioned disgust reactions, but not by conditioned taste avoidance. Experiment 4 showed that LI
of conditioned disgust reactions does not appear to be affected by a context shift from preexposure to testing phases. These
results show that the expression of LI of both conditioned taste avoidance and conditioned disgust reactions depends critically
on a common method of flavor exposure during preexposure and testing. 相似文献
5.
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
6.
Four experiments examined whether or not spontaneous recovery could occur after extinction in the conditioned taste-aversion paradigm. After three extinction trials, spontaneous recovery was obtained over an 18-day retention interval (Experiments 1, 2, and 3). The effect was not due to changes in the unconditioned preference for saccharin over the retention interval (Experiment 2) or to an increase in a nonextinguished aversion over time, as indicated by tests with both the original, nonextinguished aversion (Experiment 1) and with a weaker one (Experiment 3). Spontaneous recovery was not obtained when extinction was overtrained (eight trials) and a 49-day retention interval was used (Experiment 4). However, saccharin intake at asymptote reached the level of baseline water intake, and not the highly preferred level shown by never-conditioned controls. Results of all four experiments suggest that extinction does not return an averted taste to the status of an unconditioned one. 相似文献
7.
In two experiments, saccharin (CS) and lithium chloride (US) were paired in a context consisting of specific visual, auditory, tactual, and olfactory cues. The saccharin aversion was then extinguished in a context free from conditioning-context cues. Later, saccharin preference tests were given in the presence and absence of these cues. The results indicated that the background cues of the conditioning trial controlled the amount of saccharin drunk on extinction trials, and, furthermore, that extinction of the taste aversion was context specific; i.e., groups given extinction trials in a different (from conditioning) context retained their saccharin aversion in the conditioning context only. The results indicate an important role played by the exteroceptive context in taste-aversion conditioning. 相似文献
8.
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
9.
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
10.
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
11.
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
12.
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
13.
Separate groups of water-deprived rats had four trials with 15-min access to 0.0073 M saccharin, 0.3 M alanine, 0.3 M glucose,
0.1 M maltose, 0.3 M fructose, 0.06 M sucrose, or 0.03 M Polycose. Trials 1–3 were followed by injections of either 0.15 M
LiCl (1.33 ml/100 g b.w., i.p.) or saline; Trial 4 (Test) was CS only. Extinction included either 48-h access to water alone
or to the appropriate CS, both followed by a 24-h, two-bottle choice of CS and water. This 3-day cycle was repeated five to
six times. All rats acquired comparable conditioned taste aversions (CTAs), but extinction rates varied with the test and
the taste CS. No CTA extinguished during the two-bottle choices following 2 water days. During one-bottle CS exposure, all
CTAs extinguished, but the aversion continued longer in the probe two-bottle tests. Intake of glucose moieties recovered rapidly,
often in two cycles; the other CSs took four to six cycles. Thus, CTA extinction varies with the nature of the taste CS. 相似文献
14.
In three experiments using rats as subjects, we investigated the degree to which a conditioned flavor aversion transfers from one context to another. Experiment 1, using a one-trial conditioning procedure, found no effect of a change of context on a conditioned aversion. Experiment 2 employed a multitrial procedure and demonstrated that a conditioned aversion was extinguished more rapidly after a change of context. Experiment 3 showed that context change decreased the effectiveness with which a conditioned flavor could block acquisition of an aversion by a second flavor. It is argued that these data cannot be explained in associative terms, and that they constitute evidence of conditionality in a simple aversive conditioning procedure. 相似文献
15.
Michael J. Detke 《Learning & behavior》1991,19(4):345-354
Extinction of inhibition was examined in three pigeon autoshaping experiments. In Experiment 1, a sequential conditioned inhibitor (CI) lost inhibitory power after extinction trials. In Experiment 2, this loss of inhibition was replicated, and the effect was general to both the original target and a transfer target that was separately trained in an inhibition design. In Experiment 3, two CIs were trained simultaneously and two sequentially, and one of each was extinguished; all were tested simultaneously and sequentially. The results show that sequential testing is a necessary component for observing loss of inhibition. This is not consistent with an actual loss of inhibitory associations. It is suggested that the extinction trials either decrease processing of the CI, or extinguish its excitatory properties, to which some of the inhibition may be conditioned. 相似文献
16.
Elizabeth D. Capaldi David E. Myers David H. Campbell Joan Denise Sheffer 《Learning & behavior》1983,11(1):107-115
In five experiments, rats’ preference for a flavor was greater if the flavor had previously been consumed under low rather than high deprivation. This preference was conditioned in as few as three flavor-deprivation pairings (Experiment 1), and persisted through 28 test days, half under each deprivation level (Experiment 2). Rats never preferred the flavor associated with high deprivation even when calories were increased by giving 40 ml of 8% sucrose or when caloric density was increased to the equivalent of 20% sucrose. The preference for the low-deprivation flavor was greater when saccharin solutions were used rather than sucrose solutions, but the preference did emerge when sucrose solutions were used as testing proceeded and when a lower concentration of sucrose was used. We suggest that these preferences may be a result of flavor-taste associations rather than associations between flavors and postingestive consequences, and that the taste of the solutions under low deprivation is preferred to the taste under high deprivation. 相似文献
17.
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
18.
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
19.
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
20.
Experiment 1 investigated the effects of US habituation on the acquisition and extinction of learned taste aversions in rats. Subjects receiving five noncontingent LiCl intubations prior to conditioning failed to develop a conditioned taste aversion, while control subjects experiencing a single saccharin/LiCl pairing displayed a pronounced taste aversion which weakened during subsequent poisonings. Experiment 2 examined whether habituation, defined as a waning of responses to repeated presentation of an illness stimulus, was a possible mechanism for explaining the results of Experiment 1. Subjects showed a decrease in motor activity following an initial LiCl intubation, but less attenuation of activity with successive intubations. 相似文献