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Resurgence is the relapse of a previously reinforced and then extinguished target response when extinguishing a more recently reinforced alternative response. We designed the present study to assess the contribution of stimulus‐control and reinforcer‐control processes in determining resurgence. In a modified resurgence procedure, we removed the alternative discriminative stimulus signaling alternative reinforcement when extinguishing the alternative response. This produced more abrupt resurgence of target responding than in a typical resurgence procedure maintaining the alternative discriminative stimulus when extinguishing the alternative response. The overall amount of resurgence did not differ. Importantly, a “renewal” control added and removed the alternative stimulus during extinction, identically as in the modified resurgence procedure. However, alternative responding was never reinforced, which produced no relapse of target responding. Therefore, the more abrupt resurgence with the modified procedure than with the typical procedure suggests removing the alternative stimulus reduced the competition between alternative and target responding. These findings revealed the importance of adding and removing alternative reinforcement in producing resurgence (reinforcer control) but little influence of simply adding and removing the alternative stimulus (stimulus control). These data suggest that clinicians should consider the long‐term availability of the alternative response option when developing differential‐reinforcement interventions.

Recognition of a self‐image in a mirror is investigated using the mark test during which a mark is placed onto a point on the body that is not directly visible, and the presence or absence of self‐directed behaviors is evaluated for the mirror‐observing subjects. Great apes, dolphins, possibly elephants, and magpies have all passed the mark test, that is, displayed self‐directed behaviors, whereas monkeys, crows, and other animals have failed the test even though they were able to use a mirror to find a not‐directly‐visible object. Self‐directed behavior and mirror use are prerequisites of a successful mark test, and the absence of these behaviors may lead to false negative results. Epstein, Lanza, and Skinner (1981) reported self‐directed behavior of pigeons in front of a mirror after explicit training of self‐directed pecking and of pecking an object with the aid of a mirror, but certain other researchers could not confirm the results. The aim of the present study was to conduct the mark test with two pigeons that had received extensive training of the prerequisite behaviors. Crucial points of the training were identical topography (pecking) and the same reinforcement (food) in the prerequisite behaviors as well as sufficient training of these behaviors. After training for the prerequisite behaviors, both pigeons spontaneously integrated the learned self‐directed and mirror‐use behavior and displayed self‐directed behavior in a mark test. This indicates that pigeons display mirror self‐recognition after training of suitable ontogenetic contingency.

The discriminative functions of the response–reinforcer relation may contribute to the changes in response rates that occur when reinforcement is delayed. These properties were investigated in three experiments with pigeons using a discrete‐trials conditional discrimination procedure. A concurrent variable‐interval schedule was arranged on two side keys during a sample component. The key peck that ended the schedule (the sample response) initiated a delay with either a stimulus present throughout the delay interval (full signal), a stimulus present only during the first second of the interval (partial signal), or no stimulus present (unsignaled delay). The delay was followed by a choice component where one alternative was reinforced if the left sample response produced the choice component and the other if the right sample response produced the choice component. Accuracy was high with a full signal; slightly lower with a partial signal; and lowest without a signal. The results parallel the effects of similar delays programmed in conventional reinforcement schedules. This in turn suggests a possible discriminative effect of the response–reinforcer relation in the control of behavior by (delayed) reinforcement.

Behavioral momentum theory asserts Pavlovian stimulus–reinforcer relations govern the persistence of operant behavior. Specifically, resistance to conditions of disruption (e.g., extinction, satiation) reflects the relation between discriminative stimuli and the prevailing reinforcement conditions. The present study assessed whether Pavlovian stimulus–reinforcer relations govern resistance to disruption in pigeons by arranging both response‐dependent and ‐independent food reinforcers in two components of a multiple schedule. In one component, discrete‐stimulus changes preceded response‐independent reinforcers, paralleling methods that reduce Pavlovian conditioned responding to contextual stimuli. Compared to the control component with no added stimuli preceding response‐independent reinforcement, response rates increased as discrete‐stimulus duration increased (0, 5, 10, and 15 s) across conditions. Although resistance to extinction decreased as stimulus duration increased in the component with the added discrete stimulus, further tests revealed no effect of discrete stimuli, including other disrupters (presession food, intercomponent food, modified extinction) and reinstatement designed to control for generalization decrement. These findings call into question a straightforward conception that the stimulus–reinforcer relations governing resistance to disruption reflect the same processes as Pavlovian conditioning, as asserted by behavioral momentum theory.

In nonhuman animals, the transitive inference (TI) task typically involves training a series of four simultaneous discriminations involving, for example, arbitrary colors in which choice of one stimulus in each pair is reinforced [+] and choice of the other color is nonreinforced [−]. This can be represented as A+B−, B+C−, C+D−, D+E− and can be conceptualized as a series of linear relationships: A > B > C > D > E. After training, animals are tested on the untrained non‐endpoint pair, BD. Preference for B over D is taken as evidence of TI and occurs because B is greater than D in the implied series. In the present study we trained pigeons using a novel training procedure—a hybrid of successive pair training (training one pair at a time) and mixed‐pair training (training all pairs at once)—designed to overcome some of the limitations of earlier procedures. Using this hybrid procedure, we trained five premise pairs (A+B−, B+C−, C+D−, D+E−, and E+F−) which allowed us to test three untrained non‐endpoint pairs (BD, CE, and BE). A significant TI effect was found for most subjects on at least two out of three test pairs. Different theories of TI are discussed. The results suggest that this hybrid training is an efficient procedure for establishing mixed‐pair acquisition and a TI effect.

Two experiments were conducted to assess stimulus control and generalization of remote behavioral history effects with humans. Undergraduates first responded frequently under a fixed‐ratio (FR) schedule in the presence of one line length (16 mm or 31 mm) and infrequently on a tandem FR 1 differential‐reinforcement‐of‐low‐rate (DRL) schedule when a second line length (31 mm or 16 mm) was present. Next, an FR 1 schedule in effect in the presence of either stimulus produced comparable response rates between the stimuli. Finally, a tandem FR 1 fixed‐interval (FI) schedule was in effect under those same stimuli (Experiment 1) or under 12 line lengths ranging from 7 to 40 mm (Experiment 2). In both experiments, responses under the tandem FR 1 FI schedule were frequent in the presence of stimuli previously correlated with the FR schedule and infrequent in the presence of stimuli previously correlated with the tandem FR 1 DRL schedule. Short‐lived but systematic generalization gradients were obtained in Experiment 2. These results show that previously established rates of behavior that disappear when the establishing contingencies are changed can subsequently not only reappear when the contingencies change, but are controlled by and generalize across antecedent stimuli.

We evaluated a strategy for decreasing improperly stored dishes in a hospital unit. A humorous sign and a neutral sign were posted to remind staff to store dishes properly, and follow‐up data were collected to determine maintenance effects. Relative to baseline, fewer dishes were stored improperly when a sign was posted, regardless of sign content. These effects were maintained during a 4‐month follow‐up. Results of social validity questionnaires showed low acceptability for the humorous sign and moderate acceptability for the neutral sign.

Abstract The efficacy of nonremoval of the cup or spoon as treatment for feeding refusal is dependent on prevention of escape from presentations. In the current investigation, 1 child with feeding refusal escaped presentations during nonremoval of the cup and spoon by clenching his teeth. Therefore, we used a syringe to deposit liquids and solids, increased the volume of liquids and solids in the syringe, and conducted syringe‐to‐cup and syringe‐to‐spoon fading.

The current study involved an evaluation of the emergence of untrained verbal relations as a function of 3 different foreign‐language teaching strategies. Two Spanish‐speaking adults received foreign‐language (English) tact training and native‐to‐foreign and foreign‐to‐native intraverbal training. Tact training and native‐to‐foreign intraverbal training resulted in the emergence of a greater number of untrained responses, and may thus be more efficient than foreign‐to‐native intraverbal training.

Line tracking is a prerequisite skill for braille literacy that involves moving one's finger horizontally across a line of braille text and identifying when a line ends so the reader may reset his or her finger on the subsequent line. Current procedures for teaching line tracking are incomplete, because they focus on tracking lines with only small gaps between characters. The current study extended previous line‐tracking instruction using stimulus fading to teach tracking across larger gaps. After instruction, all participants showed improvement in line tracking, and 2 of 3 participants met mastery criteria for tracking across extended spaces.