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121.
Pigeons were given a choice between two identical-duration situations (terminal links of chain schedules). One terminal link of the choice pair provided two food deliveries, and the other provided five. The exact times of these food deliveries differed between the terminal links and were varied over conditions. A single response during the initial link gave immediate access to the corresponding terminal link. Forced trials, during which only one of the initial-link keys was lighted, were interspersed with choice trials during which both initial-link keys were lighted. Choice tended to favor whichever terminal link was correlated with the higher sum of the immediacies (i.e., the sum of the reciprocals of the delays to each of the reinforcers following the choice, with all delays measured from the choice). Latencies on forced trials and on choice trials also were related (negatively) to the sum of the immediacies. This correlation among response measures (choice and latencies) suggests that both measures are manifestations of the effect of conditioned reinforcement on response tendencies. 相似文献
122.
Five small groups of preschool children were taught to share and praise by the modelling of these behaviors and reinforcement of their reports of sharing and praising. Experiment I demonstrated that modelling and reinforcement of any (true or untrue) reports of sharing, and then of praising, promptly increased reports of the corresponding behaviors. Modelling and reinforcement for true reports of each behavior increased both reporting and actual behavior. Experiment II showed that both reported and actual sharing and praising may be increased by modelling and reinforcement for true reports of the target behavior, without previous reinforcement for any (true or untrue) reports of those behaviors. Sharing, but not praising, generalized to a second setting. Experiment III replicated the results of Experiment II for sharing and praising, and demonstrated similar success in increasing a third behavior, specific praising. In general, these experiments show that developing correspondence between children's reports of behavior and actual behavior may be an efficient means of increasing prosocial responses. 相似文献
123.
A comparison of pecking generated by serial, delay, and trace autoshaping procedures 总被引:2,自引:1,他引:1 下载免费PDF全文
Pigeons were exposed to serial, delay, and trace autoshaping procedures. In Experiment I, all conditioned stimuli (CSs) were changes in illumination of the response key. The number of trials to acquisition of the keypeck increased from serial, to 4-sec delay, 8-sec delay, and 8-sec trace procedures, in that order. In Experiment II, which used a longer intertrial interval, trials to criterion increased from 8-sec delay, to 28-sec delay, 8-sec trace, and 28-sec trace procedures, in that order. In Experiment III, two groups received serial procedures in which the first CS was either a tone or a houselight, and the second was a keylight. The tone group acquired the key peck more rapidly than the houselight group. Early in conditioning in these experiments, and when the conditioned stimulus was a change in the keylight, there was a short latency to the onset of pecking and pecking was directed at the CS. After extensive conditioning, or when the CS was relatively diffuse, pecking still occurred, but had a longer latency and was not reliably directed toward the conditioned stimulus. 相似文献
124.
Probability and delay in commitment 总被引:3,自引:2,他引:1
Rachlin H Castrogiovanni A Cross D 《Journal of the experimental analysis of behavior》1987,48(3):347-353
In the first stage of a two-stage choice, human subjects chose between probabilistic access to a second choice (between a small high-probability reward and a large low-probability reward) and commitment to the large low-probability reward. When confronted with the second-stage choice, subjects strongly preferred the small high-probability reward. When the first-stage probability (of access to the second stage) was high, subjects strongly preferred the path leading to the choice in the second stage. But when the first-stage probability was low, subjects committed themselves to the large low-probability reward. These results parallel those obtained by Rachlin and Green (1972) with pigeons and constitute some evidence that probabilities may be interpreted as delays. 相似文献
125.
Sensitivity to reinforcer duration in a self-control procedure 总被引:2,自引:2,他引:0
In a concurrent-chains procedure, pigeons' responses on left and right keys were followed by reinforcers of different durations at different delays following the choice responses. Three pairs of reinforcer delays were arranged in each session, and reinforcer durations were varied over conditions. In Experiment 1 reinforcer delays were unequal, and in Experiment 2 reinforcer delays were equal. In Experiment 1 preference reversal was demonstrated in that an immediate short reinforcer was chosen more frequently than a longer reinforcer delayed 6 s from the choice, whereas the longer reinforcer was chosen more frequently when delays to both reinforcers were lengthened. In both experiments, choice responding was more sensitive to variations in reinforcer duration at overall longer reinforcer delays than at overall shorter reinforcer delays, independently of whether fixed-interval or variable-interval schedules were arranged in the choice phase. We concluded that preference reversal results from a change in sensitivity of choice responding to ratios of reinforcer duration as the delays to both reinforcers are lengthened. 相似文献
126.
Choice behavior of rats in a concurrent-chains schedule: Amount and delay of reinforcement 总被引:16,自引:16,他引:0 下载免费PDF全文
Rats were exposed to concurrent-chains schedules in which the terminal links were equal fixed-interval schedules terminating in one or three food pellets. Choice proportions for large reward increased with increases in delay intervals programmed on fixed-interval schedules and supported the predictions derived from a general choice model originally formulated by Fantino and later developed by Navarick and Fantino. In addition, a functional equivalence of two alternatives was established by increasing delay intervals with large reward, whereas delay intervals for small reward were held constant. Functionally equivalent delay intervals with large reward, for each delay interval with small reward, can be described by a power function with exponent smaller than 1.0. A better prediction of choice proportions resulted when this function was used to derive predicted choice proportions. 相似文献
127.
Preference for unsegmented interreinforcement intervals in concurrent chains 总被引:5,自引:5,他引:0 下载免费PDF全文
Five pigeons were trained under concurrent-chain schedules in which a pair of independent, concurrent variable-interval 60-s schedules were presented in the initial link and either both variable-interval or both fixed-interval schedules were presented in the terminal link. Except for the baseline, one of the terminal-link schedules was always a two-component chained schedule and the other was either a simple or a tandem schedule of equal mean interreinforcement interval. The values of the fixed-interval schedules were either 15 s or 60 s; that of the variable-interval schedules was always 60 s. A 1.5-s changeover delay operated during the initial link in some conditions. The pigeons preferred a simple or a tandem schedule to a chain. For the fixed-interval schedules, this preference was greater when the fixed interval was 60 s than when it was 15 s. For the variable-interval schedules, the preferences were less pronounced and occurred only when the changeover delay was in effect. For a given type of schedule and interreinforcement interval, similar preferences were obtained whether the nonchained schedule was a tandem or simple schedule. The changeover delay generally inflated preference and lowered the changeover rate, especially when the terminal-link schedules were either short (15 s) or aperiodic (variable-interval). The results were consistent with the notion that segmenting the interreinforcement interval of a schedule into a chain lowers the preference for it. 相似文献
128.
The determinants of talking delay alone or its comorbidity with behavioural difficulties was examined in 5768 two-year-old members of the Growing Up in New Zealand longitudinal study. Using the MacArthur-Bates Communicative Development inventories and the total difficulties score from the preschool Strengths and Difficulties Questionnaire, a composite measure was created so that children were categorised as showing no language or behavioural concerns (72.5%), behavioural only difficulties (6.1%), language only difficulties (18.1%), and comorbid language and behavioural difficulties (3.3%). Analyses revealed that antenatal factors such as maternal perceived stress, inadequate folate intake, vitamin intake, alcohol consumption during the first trimester and maternal smoking all had a significant effect on child outcomes. In particular, low multivitamin intake and perceived stress during pregnancy were associated with coexisting language and behavioural difficulties. These findings support international research in showing that maternal factors during pregnancy are associated with developmental outcomes in the early childhood period, and demonstrate these associations within a NZ context. Interventions which address maternal stress management and health behaviours during pregnancy could be beneficial to offspring development. 相似文献
129.
130.
Luisa Schonhaut Ivan Armijo Paula Rojas B. Leonardo Cabrera Roberto Boisier 《Infant and child development》2023,32(4):e2425
to analyse the reliability of 6 age intervals of Spanish web-based Ages and Stages Questionnaires Third Edition (WB-ASQ-3) and parents' acceptability, in a clinical practice context, during COVID-19 pandemic and lockdown in Chile. Cross-sectional study with a longitudinal component. Internal consistency was analysed by Cronbach's alpha and Pearson product–moment correlation, Pearson's correlations between intervals questionnaires were analysed. Acceptability was determined using a parental satisfaction survey. 1061 children completed 2318 validated questionnaires. Scores were compared with normative sample, except for Gross motor at 8 and 12 months, and Communication at 12, 18 and 24 months, without differences to the previous Chileans sample. In domain analysis, Cronbach's alpha ranged from 0.36 to 0.80 and reached 0.74 to 0.81 for the overall test. Strong positive correlation between the domain and overall score was obtained. Correlation between most questionnaires at different ages was positive and significant. Parental surveys show high satisfaction; parents were thankful for being able to monitor children's development. WB-ASQ-3 is a reliable and feasible screening system, particularly when the test is taken as a whole, rather than by domains. It is remarkably high acceptability among parents, especially in complex times such as the lockdown and the COVID-19 pandemic. 相似文献