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1.
Gibbon  J.  Locurto  C.  Terrace  H. S. 《Learning & behavior》1975,3(4):317-324

Five groups of pigeons were studied in an auto-shaping procedure which programmed two types of trials represented by hues on the response key. Each signal was separated by a brief intertriai interval. Three groups were studied with a positive correlation between one of the signals and food (contingent groups). They differed with respect to the frequency with which the positive signal appeared. Two noncontingent groups were studied in which the correlation between the signals and food was eliminated by programming food with the same probability following either signal. One noncontingent group had a high density of reinforcement produced by adding reinforcement in the other signal, at the same rate as programmed in the positive signal for the contingent groups. The other noncontingent group experienced the same number of reinforcements in the session as the contingent group with the least frequent positive trial, but these reinforcements were distributed with equal probability across the signals. Birds in the contingent groups with intermediate or infrequent positive signals all acquired reliable pecking, with acquisition most rapid for the infrequent signal. Maintained responding covaried with the speed of acquisition. No birds in the noncontingent groups showed reliable responding. Birds in the contingent group with a frequent positive signal (approximately 3/4 of the session), also showed no reliable pecking. This result suggests that more than one noncontingent group is informative for assessing the role of differential reinforcement probability in the acquisition of auto-shaped keypecking. In particular, a noncontingent group which controls for the frequency of reinforced trials is an appropriate reference group.

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2.
The effect of noncontingent outcomes on an instrumental response-outcome (R-O) association was examined in four experiments using transfer tests. In each experiment, rats were first given instrumental discrimination training designed to establish different stimuli as signals (S+s) for different outcomes. Transfer responses were subjected to different treatments across the experiments and then tested with the S+s. In Experiments 1 and 2, two transfer responses were both initially trained with two contingent outcomes. Then, each transfer response was subjected either to the addition of noncontingent presentations of one of those outcomes (Experiment 1) or to the replacement of one of the contingent outcomes with noncontingent presentations of that outcome (Experiment 2). Transfer tests revealed no significant difference in the ability of an S+ to promote performance of a transfer response based on their shared association with either the contingent or the noncontingent outcome. These results suggest that a response reinforced with two outcomes remains equally well associated with both of those outcomes despite prolonged exposure to noncontingent presentations of one of those outcomes. In Experiments 3 and 4, the possibility that the noncontingent schedules of reinforcement used in Experiments 1 and 2 might be capable of establishing an association between a response and its noncontingent outcome was examined. Transfer responses were trained with one contingent outcome and a different noncontingent outcome. Performance of these transfer responses was augmented more by presentations of an S+ trained with the contingent outcome than with the noncontingent outcome. These results confirm previous reports that instrumental responses are sensitive to outcome contingencies in acquisition and that noncontingent outcome presentations do not weaken previously established R-O associations. Several explanations are considered for the failure of subsequent noncontingent presentations of an outcome to reduce the strength of its association with the instrumental response.  相似文献   

3.
Four pigeons responded on a two-component multiple token-reinforcement schedule, in which tokens were produced according to a random-interval 30-sec schedule and exchanged according to a variable-ratio 4 schedule in both components. To assess the effects of contingent token loss, tokens were removed after every second response (i.e., fixed-ratio 2 loss) in one of the components. Response rates were selectively lower in the loss components relative to baseline (no-loss) conditions, as well as to the within-condition no-loss components. Response rates were decreased to a greater degree in the presence of tokens than in their absence. To control for the effects of changes in the density of token and food reinforcement, two parts consisted of additional conditions where food density and token loss were yoked to those in a previous loss condition. In the yoked-food condition, tokens were produced as usual in both components, but the overall density of food reinforcement in one of the components was yoked to that obtained during a previous token-loss condition. In the yoked token-loss condition, tokens were removed during one component of the multiple schedule at a rate that approximately matched the obtained rate of loss from a previous token-loss condition. Response rates in these yoked components were less affected than those in comparable loss components, despite similar densities of token, exchange, and food reinforcement. On the whole, the results support the conclusion that contingent token loss serves as an effective punisher with pigeons.  相似文献   

4.
Premack’s probability hypothesis provides a simple empirical rule for predicting reinforcement effects, but has always been applied to response probabilities estimated by averaging over entire sessions. If the rule is robust, it should also predict momentary (e.g., within-sessions) changes in reinforcement from parallel momentary probability changes. It seems to do so. Six rats received noncontingent water (base), then leverpressed for water (contingency), each for 15 sessions. All sessions were divided into six subsessions. Average leverpressing for individual rats was a simple monotonie, usually linear, function of the probability of drinking—estimated from that subsession ’s counterpart during base. Similar results were obtained from a second study even though different instrumental and contingent events were used. With some generality, then, it is possible to apply the probability hypothesis to momentary reinforcement effects.  相似文献   

5.
A series of four experiments, employing mice, investigated the generality of the learned helplessness phenomenon. The first two experiments used preexposure to aversive stimuli (shock), while the other two used preexposure to appetitive stimuli (food). In all of the studies, subjects were preexposed to contingent, noncontingent, or no stimuli (except for Experiment 2) in a Skinner box. During the test, animals preexposed to shock were tested with food, and those preexposed to food were tested with shock. The test was conducted in a similar situation, a Skinner box (Experiments 1, 3), or a different situation—a runway (Experiments 2, 4). Performance decrements were evident when subjects that were preexposed to a noncontingent stimulus were compared with subjects preexposed to contingent stimuli. The differences between the contingent and the noncontingent groups were significant, as were the differences between the contingent and the nonpreexposed groups (except for Experiment 1). The effects cut across the different types of stimuli, situations, and response requirements of the preexposure and test phases.  相似文献   

6.
3-month-old infants who can activate a mobile with their spontaneous leg kicks increase their kick rate over baseline. Kinematic analyses of the temporal and topographic characteristics of reinforced leg kicks were compared with those of infants who saw noncontingent mobile movement. In both experimental and control groups, the flexion and extension movement phases of the kick remained remarkably invariant in duration. Pauses between movements varied inversely with rate. Kick amplitude increased with increasing rate except in the extinction phase, where in some infants, kicks became less frequent but more forceful. Movement duration was unaffected by reinforcement condition. By varying amplitude and frequency domains, infants adjusted movement by neuromuscular mechanisms similar to those of mature humans. The experimental imposition of a voluntary component on spontaneous kicking did not alter the modifiability of the movement control parameters.  相似文献   

7.
Undeprived hamsters received nest paper or sunflower seeds in their home cages, free or contingent on one of three activities. The pattern of effects of reinforcement was the same as that reported previously with food for hungry hamsters in an open field: Open rearing and scrabbling quickly increased in rate when reinforced with paper or seeds, but face washing showed little or no increase. Certain interrelations found previously between noncontingent effects of reinforcers, deprivation effects, and contingent effects were absent and therefore are not essential to the differences among these three behaviors during reinforcement. The hamsters could learn to interrupt fact washing to collect either paper or seeds, but even then they did not increase their time face washing to high levels. Raising the operant level of face washing by spraying the animals with water did not improve instrumental performance. Face washing could be classified as an involuntary activity, but this term does not provide a full account of its special properties, such as shortened bouts, during reinforcement and punishment.  相似文献   

8.
We conducted three studies which examined the performance vs. skill acquisition model of social skills deficits. In Study 1, baseline social behaviors for a random sample of 12 boys with comorbid emotional and behavioral disorders (EBD), learning disabilities (LD), language delays, and Attention Deficit Hyperactivity Disorder (ADHD) revealed that prosocial behaviors as well as inappropriate behaviors exist comorbidly in behavioral repertoires, supporting a performance rather than acquisition model of social competence difficulties. In Study 2, an ABAC design was used to examine the efficacy of a self‐management intervention with noncontingent (B) and contingent (C) reinforcement for three elementary aged boys with EBD. Generalization was demonstrated in natural settings for the contingent reinforcement phase only, but was not observed over time. Study 3 replicated Study 2's procedures using an ABAC multiple baseline across participants design with a sample of adolescents with varying degrees of mental retardation. Two of the three participants responded favorably to the self‐monitoring training and showed marked improvements in prosocial play skills during recess; for the third participant, no behavioral changes were observed. Results from all three studies are discussed from a social learning theory perspective. The efficacy of the data collecting procedure and implications of the results are discussed. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 351–372, 2007.  相似文献   

9.
We examined immunization against learned helplessness in 36 dogs. The experiment consisted of five phases: (1) appetitive contingent training, (2) immunization training, (3) inescapable noise training, (4) recovery, and (5) an appetitive noncontingent test. There were six groups: (1) a group immunized by controllable and predictable noise, (2) a group immunized by controllable but unpredictable noise, (3) a group immunized by uncontrollable but predictable noise, (4) a group given uncontrollable and unpredictable noise during immunization training, (5) a group not submitted to any treatment during the immunization phase, followed by uncontrollable noise, and (6) a group not submitted to any treatment. The immunization effect was assessed by measuring the acquisition of an appetitive response when food was not contingent upon responding. Our results demonstrate that the immunization effect can be observed in a noncontingent appetitive context. The effects of escapable noises that ensure immunization against the motivational deficit and predictable noises that immunize against the associative deficit seem to be additive.  相似文献   

10.
Rats increased eating that produced access to a running-wheel or increased running that produced access to food, depending on which response was potentially deprived, relative to baseline, by the scheduled ratio of responding. Under both schedules, instrumental responding significantly exceeded appropriate baselines of the noncontingent effects of the schedule. The results contradicted the hypothesis that reinforcement is produced by an overall or momentary probability differential between two responses; instead, they supported the condition of response deprivation as a key determinant of reinforcement. Of several recent quantitative models that predict reversibility of reinforcement by schedule changes, only the predictions of the relative response-deprivation model did not differ significantly from the data of either schedule.  相似文献   

11.
Self‐worth protective students characteristically perform well on some occasions yet on other occasions they perform poorly. In this study, two accounts of the poor performance of self‐worth protective students are assessed. The first is that their poor performance is an outcome of evaluative threat. The second is that their poor performance is an outcome of future outcome uncertainty: a product of their uncertain global self‐esteem and uncertainty about the causes of achievement outcomes. Students high or low in self‐worth protection were exposed to either noncontingent success (creating future outcome uncertainty), noncontingent failure (evoking evaluative threat), or contingent success. Their ability to solve two tasks that involved a high degree of uncertainty was then assessed. Students high in self‐worth protection performed poorly following both noncontingent failure and noncontingent success, supporting the roles of both evaluative threat and future outcome uncertainty. The implications in terms of enhancing the achievement of students high in self‐worth protection are discussed.  相似文献   

12.
Developmental changes in conditions engendering pride and embarrassment were explored. Subjects included 41 adults and 189 5-, 7-, 9-, and 11-year-old children from diverse ethnic backgrounds. Subjects were asked to report events that had made them feel proud, embarrassed, happy, and sad. Content analyses of responses concerning pride and embarrassment indicated that references to noncontingent, uncontrollable events decreased with age, but most 5-year-olds understood that feelings of pride and, to a lesser extent, embarrassment result primarily from outcomes controlled by and contingent on one's own behavior or characteristics. Responses of children in all 4 age groups and adults suggest that an audience is important for both pride and embarrassment, but particularly for embarrassment. An audience and external reinforcement were more important in children's than in adults' reports of pride. Developmental change was found in the standards used to evaluate emotional experiences; references to social comparison increased with age and references to mastery decreased.  相似文献   

13.
Separation of the contingent and noncontingent effects of a schedule on amount of instrumental responding is desirable but difficult in schedules that involve instrumental and contingent responses that are either highly probable or very similar. Three studies in which rats were required to lick a solution of .1% saccharin for access to a preferred solution of .4% saccharin showed that neither single nor paired operant baselines of the instrumental response allowed accurate separation of the contingent and noncontingent effects of a fixed-ratio schedule. Two within-subject yoking procedures provided the best baselines of noncontingent effects: the massed baseline measured amount of .1% licking when each subject received free access to the total amount of .4% licking it obtained at asymptote under the schedule; the matched baseline measured .1% licking when each subject received the same access to the .4% solution, but presented in the intermittent pattern obtained during the schedule. Of the three algebraic models used to predict noncontingent effects, the substitution model was most promising, but still not adequate. The procedure of a between-subjects yoked control was also not effective.  相似文献   

14.
15.
For three groups of rats, an auditory CS, presented while the animals were responding on a variable-interval schedule for food reinforcement, was terminated on half of the trials with a noncontingent footshock. For two groups, half of the trials were also followed after 5 sec by the delivery of free food. In the positively correlated condition (PC) the free food was presented on shocked trials and in the negatively correlated condition (NC) on the nonshocked trials, while the remaining group (S) never received free food. In a fourth group the shock was omitted and free food delivered on half of the trials. Although all shocked groups showed a significant suppression, the magnitude was greater for Group PC than for Groups NC and S, which did not differ. Suppression did not result from the pairing of the CS with food alone. These results do not support the counterconditioning hypothesis that the pairing of a normally noxious stimulus with food reduces its aversiveness.  相似文献   

16.
A noncontingent experience affects the subsequent detection of positive and negative contingencies between the same events. Experiments 1 and 2 showed that such preexposure can produce both an impairment in the detection of subsequent positive contingency and a facilitation of a negative one, independent of the level of contingency during the contingent phase. Experiment 3 raised difficulties for a model that assumes that associations to the context can explain this asymmetrical effect. Experiment 4 suggested that the different weights usually assigned to the different types of trials when computing the contingency between events can change as a result of a noncontingent experience with the same events. This change supports an account of the asymmetrical effect by a belief revision model based on a mechanism that updates the weights of the different trial types as a function of previous experience. More generally, the belief revision model is a statistical (i.e., nonassociative) model of learning that is capable of accounting for trial-order effects, which have long posed problems for statistical models.  相似文献   

17.
Operant responses are often weakened when delays are imposed between the responses and reinforcers. We examined what happens when delayed reinforcers were contingent upon operant responsevariability. Three groups of rats were rewarded for varying their response sequences, with one group rewarded for high variability, another for middle, and the third for low levels. Consistent with many reports in the literature, responding slowed significantly in all groups as delays were lengthened. Consistent with other reports, large differences in variability were maintained across the three groups despite the delays. Reinforced variability appears to be relatively immune to disruption by such things as delays, response slowing, prefeeding, and noncontingent reinforcement. Furthermore, the small effects on variability depended on baseline levels: As delays lengthened, variability increased in the low group, was statistically unchanged in the middle group, and decreased in the high group, an interaction similar to that reported previously when reinforcement frequencies were lowered. Thus, variable operant responding is controlled by reinforcement contingencies, but sometimes differently than more commonly studied repetitive responding.  相似文献   

18.
3 experiments with 3-month-old infants compared the effects of contingent and noncontingent adult-infant social interactions on subsequent infant-controlled habituation and choice tasks. Infants who experienced a prior noncontingent social interaction tended to adopt response strategies that reduced the density of stimulation during these subsequent nonsocial tasks. The results are discussed in terms of their generality and the types of mechanisms that might mediate these transfer effects from social to nonsocial procedures.  相似文献   

19.
In two experiments, pigeons' responding on an extraneous task was explicitly reinforced during delayed matching-to-sample trials. In Experiment 1, red or green sample stimuli were followed by retention intervals of 0.2, 1, 4, or 12 sec, during which pecks to a white center key were reinforced with 2.5-sec access to wheat according to extinction, variable-interval 30-sec, and variable-interval 15-sec schedules in different conditions. A proportion of .2, .5, .7, or .9 of subsequent red or green choice responses that matched the sample were reinforced with 3-sec access to wheat. The result was that increasing center key reinforcement, or reducing reinforcer probability, lowered overall accuracy. Initial discriminability fell, but with no change in the rate of forgetting. In Experiment 2, initial discriminability was affected by extraneous reinforcers that were contingent on center key pecking, but not by noncontingent reinforcers. A plausible conclusion is that initial discriminability decreases when reinforcers strengthen competing behaviors.  相似文献   

20.
The effects of two types of self-determined reinforcement contingencies on children's test performances were investigated and compared to each other and to externally determined contingencies. In Experiment I, fourth-grade children's test performances were measured for three baseline sessions utilizing self-assessment and self-recording and three contingency sessions. Three contingency conditions resulted in significant and comparable increases in total test performances over a noncontingent reinforcement control: externally determined contingencies set in advance of performance, self-determined contingencies set in advance of performance when children were trained in contingency selection, and self-determined contingent points that children awarded themselves after performance. In a condition in which children self-determined contingencies but had no training in how to set contingencies, the results were not significantly greater than the control. In Experiment II, contingencies were introduced for a longer period of time to two fifth-grade classes. The comparable increases in test performance through externally determined and self-determined contingencies set in advance of performance when children were trained in contingency selection persisted over the three weeks. It was suggested that self-management that includes self-determined contingencies of reinforcement procedures may provide useful and cost effective techniques that educational consultants may recommend for classroom implementation.  相似文献   

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