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Behavior analysts have implemented and evaluated several antecedent strategies for treating pediatric feeding problems. The extent to which antecedent interventions are beneficial, however, is not yet clear. This review examines recent research in the Journal of Applied Behavior Analysis (2000–2012) that evaluated antecedent interventions. We found that the feeding diagnosis (food refusal vs. food selectivity) and presence of feeding‐related medical conditions were related to the differential implementation of antecedent interventions.

Com o objetivo de investigar o controle por regras, 10 universitários foram expostos a um procedimento de escolha de acordo com o modelo; a tarefa era apontar três estímulos de comparação em uma sequência correta. Na Sessão 1 nenhuma sequência era reforçada ou instruída. As contingências da Sessão 2 eram alteradas na Sessão 3, e as contingências da Sessão 3 eram mantidas inalteradas na Sessão 4, iniciada com a regra discrepante. Os participantes eram solicitados a descrever as contingências durante as sessões e foram distribuídos em dois grupos, que diferiam porque a sequência correta na Sessão 2 era estabelecida por reforço diferencial no Grupo RD e por regra no Grupo IN. Os participantes que responderam corretamente na Sessão 3 tenderam a deixar de seguir a regra discrepante na Sessão 4; e os que responderam incorretamente na Sessão 3 tenderam a seguir a regra discrepante na Sessão 4. Um participante, na Sessão 2, formulou uma autorregra antes de o comportamento por ela especificado ter sido estabelecido por suas consequências imediatas. Neste caso, o comportamento especificado pela autorregra permaneceu inalterado nas primeiras tentativas da Sessão 3. Discutem-se os efeitos de perguntas, regras, autorregras, consequências e histórias do ouvinte sobre o comportamento.

We taught social responses to young children with autism using an adult as the recipient of the social interaction and then assessed generalization of performance to adults and peers who had not participated in the training. Although the participants' performance was similar across adults, responding was less consistent with peers, and a subsequent probe suggested that the recipient of the social behavior (adults vs. peers) controlled responding. We then evaluated the effects of having participants observe a video of a peer engaged in the targeted social behavior with another peer who provided reinforcement for the social response. Results suggested that certain irrelevant stimuli (adult vs. peer recipient) were more likely to exert stimulus control over responding than others (setting, materials) and that video viewing was an efficient way to promote generalization to peers.

Nonhuman animals show evidence for three types of concept learning: perceptual or similarity‐based in which objects/stimuli are categorized based on physical similarity; relational in which one object/stimulus is categorized relative to another (e.g., same/different); and associative in which arbitrary stimuli become interchangeable with one another by virtue of a common association with another stimulus, outcome, or response. In this article, we focus on various methods for establishing associative concepts in nonhuman animals and evaluate data documenting the development of associative classes of stimuli. We also examine the nature of the common within‐class representation of samples that have been associated with the same reinforced comparison response (i.e., many‐to‐one matching) by describing manipulations for distinguishing possible representations. Associative concepts provide one foundation for human language such that spoken and written words and the objects they represent become members of a class of interchangeable stimuli. The mechanisms of associative concept learning and the behavioral flexibility it allows, however, are also evident in the adaptive behaviors of animals lacking language.

We deployed the Multiple Necessary Cues (MNC) discrimination task to see if pigeons can simultaneously attend to four different dimensions of complex visual stimuli. Specifically, we trained nine pigeons ( Columba livia ) on a go/no go discrimination to peck only 1 of 16 compound stimuli created from all possible combinations of two stimulus values from four separable visual dimensions: shape (circle/square), size (large/small), line orientation (horizontal/vertical), and brightness (dark/light). Some of the pigeons had CLHD (circle, large, horizontal, dark) as the positive stimulus (S+), whereas others had SSVL (square, small, vertical, light) as the S+. We recorded touchscreen pecking during the first 15 s that each stimulus was presented on each training trial. Discrimination training continued until pigeons' rates of responding to all 15 negative stimuli (S‐s) fell to less than 15% of their response rates to the S+. All pigeons acquired the MNC discrimination, suggesting that they attended to all four dimensions of the multidimensional stimuli. Learning rate was similar for all four dimensions, indicating equivalent salience of the discriminative stimuli. The more dimensions along which the S‐s differed from the S+, the faster was discrimination learning, suggesting an added benefit from increasing perceptual disparities of the S‐s from the S+. Finally, evidence of attentional tradeoffs among the four dimensions was seen during discrimination learning, raising interesting questions concerning the possible control of behavior by elemental and configural stimuli.

In experiments on operant behavior, other activities, called “background” activities, compete with the operant activities. Herrnstein's ( ) formulation of the matching law included background reinforcers in the form of a parameter r O , but remained vague about the activities ( B O ) that produce r O . To gain more understanding, we analyzed data from three studies of performance with pairs of variable‐interval schedules that changed frequently in the relative rate at which they produced food: Baum and Davison ( ), Belke and Heyman ( ), and Soto, McDowell, and Dallery (2005). Results sometimes deviated from the matching law, suggesting variation in r O . When r O was calculated from the matching equation, two results emerged: (a) r O is directly proportional to B O , as in a ratio schedule; and (b) r O and B O depend on the food rate, which is to say that B O consists of activities induced by food, as a phylogenetically important event. Other activities unrelated to food ( B N ) correspond to Herrnstein's original conception of r O and may be included in the matching equation. A model based on Baum's (Baum, 2012) concepts of allocation , induction , and contingency explained the deviations from the matching law. In the model, operant activity B , B O , and B N competed unequally in the time allocation: B and B O both replaced B N , B O replaced lever pressing (Soto et al.), and key pecking replaced B O (Baum & Davison). Although the dependence of r O and B O on food rate changes Herrnstein's ( ) formulation, the model preserved the generalized matching law for operant activities by incorporating power‐function induction.

Abstract V. Mark Durand's (2013) book, Autism Spectrum Disorder: A Clinical Guide for General Practitioners , eases readers into the vast scientific literature on individuals with autism spectrum disorder (ASD), encourages behavior analysts to examine our place in this literature, and illustrates how we might communicate effectively with a general audience. Durand shows that we have developed many beneficial interventions for individuals with ASD yet may harbor obsolete views about what ASD is. Moreover, his description of ASD suggests that we should consider expanding our range of treatment targets and serve a broader segment of the ASD population. He also shows that investigators in disciplines outside applied behavior analysis (ABA) have contributed to understanding the causes and characteristics of ASD. Thus, rather than focusing mainly on ABA, Durand portrays ABA as one of many disciplines engaged in productive research on ASD; this portrayal may be both accurate and effective as a communication strategy.

Abstract On multiple fixed‐ratio schedules, pausing is extended at the start of a component ending in a small reinforcer (a lean component) but only when this component follows a component ending in a large reinforcer (a rich component). In two experiments, we assessed whether a stimulus correlated with a lean component is aversive and how its function is affected by the preceding component. In Experiment 1, pigeons responded on mixed fixed‐ratio schedules ending in large or small reinforcers. Observing responses converted the mixed schedule to a multiple one by producing a stimulus correlated with the current component. Overall, the lean stimulus did not suppress observing, suggesting that it was not sufficiently aversive. In Experiment 2, an escape procedure was used, and pigeons could convert a multiple schedule to a mixed one by pecking a key to remove the discriminative stimuli. Pigeons escaped from the lean‐schedule stimulus more than they did from the rich one. For two pigeons, this effect was enhanced when a rich component preceded the lean stimulus. The results indicate that a stimulus correlated with the leaner of two reinforcement schedules can acquire aversive functions, but observing and escape procedures may differ in their abilities to detect this effect.