Journal of the experimental analysis of behavior最新文献

Dogs may be relinquished to shelters and are unlikely to be adopted if they engage in problem behavior. A successful way to eliminate problem behavior is through training techniques based on behavioral principles. Obedience training with the use of positive reinforcement has been successful in treating problematic behavior by dogs. In order for this method to work, it is essential that the stimuli selected function as reinforcers. Preference assessments can be used to identify these potential reinforcers. A preference assessment is a systematic method used to identify stimuli that may serve as possible reinforcers by yielding preference hierarchies. Although preference and reinforcer assessments have been successfully used with humans, research with nonhuman animals is limited. Therefore, the purpose of the study was to compare the efficacy and efficiency of paired-stimulus preference assessment with a multiple-stimulus preference assessment. The results suggested that the results of both preference assessments corresponded with reinforcer assessments but that the paired-stimulus method was the most efficient.

A cross-cultural comparison is made of delay discounting in samples of participants from Chile and China. Comparisons are made based on previous literature that suggests that individuals from an Asian culture should be willing to postpone delayed rewards more than are individuals from a Latin American culture. To test the cross-cultural validity of a hyperbolic discounting model, the model was fitted to both data sets. Additionally, a self-enhancement measure was evaluated as a potential mediator between culture of origin and delay discounting. Seventy-eight college students from China and 120 college students from Chile, with similar demographic backgrounds, discounted hypothetical monetary outcomes using an adjusting-amount titration procedure. Additionally, participants completed a self-enhancement measure. Age, academic major, gender, and grade point average were controlled. Chilean participants discounted much more steeply than Chinese nationals did. No support was obtained for the mediation of self-enhancement between culture of origin and degree of delay discounting. In both samples, delay discounting was better described by a hyperboloid than an exponential function, the only exception being the $10,000 condition in which the medians for Chilean participants' present subjective value were equally well explained by a hyperboloid and an exponential function.

Organisms may sometimes behave as if a contingency exists between behavior and consequences, even if this is not actually the case. Killeen (1978) suggested that such superstition occurs because of factors that bias subjects to behave “superstitiously” rather than because of failures of discrimination. We systematically replicated Killeen's experiment and compared contingency discrimination between different consequences. Six pigeons responded in a matching-to-sample procedure in which a response-independent or response-dependent stimulus change, food delivery, or blackout occurred. The pigeons reported whether the consequence was response dependent or response independent by choosing between two side keys. Discrimination was strongest after stimulus changes, weaker after blackouts, and weakest after food deliveries. These differences persisted even after additional training, suggesting asymmetries that may reflect differences in the disruptive effects of different consequences on remembering and/or behavioral mnemonics. Importantly, the pigeons were not biased to report response-dependent consequences unless that response was consistent with locational biases; that is, they behaved “superstitiously” when there was a reason to be biased to do so. These findings corroborate Killeen's and demonstrate that behavior may deviate from contingencies not necessarily because subjects cannot discriminate those contingencies but because they are biased to behave otherwise.

Sidman's (2000) theory of stimulus equivalence states that all positive elements in a reinforcement contingency enter an equivalence class. The theory also states that if an element from an equivalence class conflicts with a reinforcement contingency, the conflicting element will “drop out” of the class. Minster et al. (2006) found evidence that a conflicting reinforcer does not drop out of an equivalence class. To explain their results, they proposed that the reinforcer enters the class via pairing after conditional relations have been established, and when there is a conflict between the class and the contingencies, conditionally related elements that have a longer history in the class and that were brought in via reinforcement will exert stronger control. In the current study, stimulus-reinforcer relations were established before conditional relations to assess the role of developmental order of stimulus relations on conditional-discrimination performance. The results replicate the findings of Minster et al. (2006) but suggest that developmental order may not be an important factor contributing to maintained accuracy on baseline conditional relations. An interpretation of “dropping out” in terms of differentiated subclasses is discussed. The relevance of the results to the phenomenon known as the differential outcomes effect is also discussed.

Studying relating of relational networks is a complex and challenging task. The main objective of the present study was to demonstrate relating within and across relational networks based on same/opposite and bigger/smaller contextual cues and establish antecedent control. After nonarbitrary pretraining of the contextual cues, two nonsense stimulus classes were established based on comparative relations. Participants were trained to select stimuli from an array of options based on a symbolic rule that established a relation between two stimuli: one of Network 1 and one of Network 2. Training involved relating Network 1 to Network 2, and testing assessed relating Network 2 to Network 1. Seven of eight participants reached the mastery criterion in training and responded accordingly in test. In a final stage, reinforcing and punishing consequences were varied systematically in the presence of two novel stimuli and antecedent control was observed for all 7 participants. Experiment 2 replicated the results of Experiment 1 but using contextual cues taken from natural language, and Experiment 3 sought to understand the effects of pretraining relational responding using natural language. The mastery criteria were reached by four of seven participants in Experiment 2 and by all eight participants in Experiment 3. Future studies could develop and refine the methods employed here in analyzing the relating of relational networks, thus allowing for an increasingly sophisticated behavior-analytic account of human language and cognition.

Response-independent schedules involve the delivery of an item independent of a response requirement. Often described in the applied behavior analytic literature as “noncontingent reinforcement,” they have also frequently been used to reduce undesired or problematic behaviors. The current study examined the use of an automated response-independent food schedule on the behaviors and sound levels of shelter dogs. Several dogs were included in a 6-week reversal design, where a fixed-time 1 min schedule was compared with a baseline condition. Eleven behaviors were measured, as were two areas of each kennel and the overall and session sound intensity (dB) that occurred during the study. The results demonstrated that the fixed-time schedule increased overall activity while decreasing inactivity and led to a reduction in the overall sound intensity measured. Session and hour-to-hour sound-intensity data were less clear, suggesting a potential contextual conditioning effect as well as a need for adjusted methods to study shelter sound. The above are discussed in terms of their potential welfare benefits for shelter dogs as well as the translational approach that this and similar research could contribute to the application and functional understanding of response-independent schedules.

Incidental bidirectional naming (Inc-BiN) has been defined as a verbal developmental cusp whereby children demonstrate learning the names of things as listener and speaker as a function of observation alone. Stimulus characteristics have been found to affect performance in tests for Inc-BiN. To further explore this effect, Experiment 1 compared untaught listener and speaker responses for novel familiar-type versus novel nonfamiliar-type stimuli with 20 first-grade students following naming experiences in which the participants observed each visual stimulus five times while hearing its name. Participants performed significantly better with familiar-type than with nonfamiliar-type stimuli. Experiment 2 examined the effects of a repeated-probe intervention to induce Inc-BiN with nonfamiliar-type stimuli. Participants were six first-grade students who demonstrated incidental unidirectional naming (i.e., acquired names as listener from exposure alone). Implementation of the intervention was staggered across dyads of participants in a multiple-probe, simultaneous-treatments design. One participant in each dyad received the intervention with nonfamiliar-type stimuli only and the other with both nonfamiliar- and familiar-type stimuli. Pre- and postintervention Inc-BiN probes with stimuli not included in the intervention suggested both conditions were effective in establishing Inc-BiN for nonfamiliar-type stimuli. These findings have implications for understanding the mechanisms underlying Inc-BiN.

Conceptual behavior represents a type of complex stimulus control where an organism differentially responds to examples and nonexamples of instances within a stimulus class. Different species have demonstrated conceptual behavior both in their natural environments and through experimental investigations. The current paper investigates preliminary methods to teach conceptual behavior to gray wolves (Canis lupus). The researchers used a match-to-sample arrangement to teach three shapes: a triangle, square, and cross varying in size, color, and positions. Probe trials used a novel set of stimuli to test for the emergence of conceptual behavior. Although the wolves did not show an immediate transfer to novel stimuli following initial match-to-sample training, they did show improvement after explicit discrimination training. We discuss the implications of these results as well as future methods that may enhance experimental procedures investigating concept learning in canids.