A zero-bounded model of operant demand

Contemporary approaches for evaluating the demand for reinforcers use either the Exponential or the Exponentiated model of operant demand, both derived from the framework of Hursh and Silberberg (2008). This report summarizes the strengths and complications of this framework and proposes a novel implementation. This novel implementation incorporates earlier strengths and resolves existing shortcomings that are due to the use of a logarithmic scale for consumption. The Inverse Hyperbolic Sine (IHS) transformation is reviewed and evaluated as a replacement for the logarithmic scale in models of operant demand. Modeling consumption in the “log₁₀-like” IHS scale reflects relative changes in consumption (as with a log scale) and accommodates a true zero bound (i.e., zero consumption values). The presence of a zero bound obviates the need for a separate span parameter (i.e., k) and the span of the model may be more simply defined by maximum demand at zero price (i.e., Q₀). Further, this reformulated model serves to decouple the exponential rate constant (i.e., α) from variations in span, thus normalizing the rate constant to the span of consumption in IHS units and permitting comparisons when spans vary. This model, called the Zero-bounded Exponential (ZBE), is evaluated using simulated and real-world data. The direct reinstatement ZBE model showed strong correspondence with empirical indicators of demand and with a normalization of α (ZBEn) across empirical data that varied in reinforcing efficacy (dose, time to onset of peak effects). Future directions in demand curve analysis are discussed with recommendations for additional replication and exploration of scales beyond the logarithm when accommodating zero consumption data.     

Resistance to extinction versus extinction as discrimination

The hypothesis that response strength might be measured by persistence of responding in the face of extinction was discredited in the 1960s because experiments showed that responding persists longer following intermittent reinforcers than following continuous reinforcers. Instead, researchers proposed that the longer persistence following intermittent reinforcers arises because intermittent reinforcement more closely resembles extinction—a discrimination theory. Attention to resistance to extinction revived because one observation seemed to support the persistence hypothesis: Following training on a multiple schedule with unequal components, responding usually persisted longer in the formerly richer component than in the formerly lean component. This observation represents an anomaly, however, because results with single schedules and concurrent schedules contradict it. We suggest that the difference in results arises because the multiple-schedule procedure, while including extensive training on stimulus discrimination, includes no training on discrimination between food available and food unavailable, whereas comparable single- and concurrent-schedule procedures include such training with repeated extinction. In Experiment 1, we replicated the original result, and in Experiment 2 showed that when the multiple-schedule procedure includes training on food/no-food discrimination, extinction following multiple schedules contradicts behavioral momentum theory and agrees with the discrimination theory and research with single and concurrent schedules.     

Behavioral ephemera,difficult discriminations,and behavioral stability

Every species possesses abilities for successfully interacting with its environment. These result from phylogeny. In the laboratory, one may arrange artificial conditions that thwart an organism's abilities. The result may be a “phenomenon.” With sufficient training, however, the phenomenon may prove to be ephemeral, as the organism's basic abilities reassert themselves. Pigeons respond extremely well to differences and nondifferences in rate of obtaining food. This ability may be thwarted in a variety of ways, but the results tend to be ephemeral. An example is an experiment that pitted pigeons' preference for unimpeded responding against their ability to respond to food rate. In a concurrent-chains procedure, the terminal links were identical variable-interval schedules, but in one terminal link, every response produced a timeout. The duration of the timeout varied, and preference varied with it, but the relation vanished with training, in keeping with the equality of food rate across the 2 terminal links. Some other examples of “phenomena” that tend to disappear with sufficient training and sufficient variation in experimental parameters are behavioral contrast, conditioned reinforcement, resistance to extinction, and suboptimal choice. These “phenomena” depend on pigeons' failing to make difficult discriminations. They appear to be behavioral ephemera.     

Brief Behavioral Activation Treatment for Depressed Adolescents Delivered by Nonspecialist Clinicians: A Case Illustration

Behavioral activation (BA) can be as effective as cognitive-behavioral therapy for the treatment of depression in adults, but to date there is little research with adolescents. This is problematic given the recognized need to increase access to evidence-based interventions for depression in young people. We have developed a new adaptation of brief Behavioral Activation (Lejuez, Hopko, Acierno, Daughters, & Pagoto, 2011) specifically for young people: Brief BA for depressed adolescents. In this paper, we use a case example with session-by-session measurement to show how a nonspecialist clinician can deliver this intervention successfully. We discuss the key themes arising from this training case, challenges the clinician faced, and how these were managed through training and supervision.     

Striving Towards Empowerment and Medication Adherence (STEP-AD): A Tailored Cognitive Behavioral Treatment Approach for Black Women Living With HIV

In the U.S. Black women with HIV face numerous psychosocial challenges, particularly trauma, racism, HIV-related discrimination, and gender role expectations, that are associated with negative HIV health outcomes and low medical treatment adherence. Yet many of these factors are unaddressed in traditional cognitive behavioral approaches. This study presents a case series of a tailored cognitive behavioral treatment approach for Black women living with HIV. Striving Towards EmPowerment and Medication Adherence (STEP-AD) is a 10-session treatment aimed at improving medication adherence for Black women with HIV by combining established cognitive behavioral strategies for trauma symptom reduction, strategies for coping with race- and HIV-related discrimination, gender empowerment, problem-solving techniques for medication adherence, and resilient coping. A case series study of five Black women with HIV was conducted to evaluate the preliminary acceptability and feasibility of the treatment and illustrate the approach. Findings support the potential promise of this treatment in helping to improve HIV medication adherence and decrease trauma symptoms. Areas for refinement in the treatment as well as structural barriers (e.g., housing) in the lives of the women that impacted their ability to fully benefit from the treatment are also noted.     

Traduction et adaptation du TEI-SF afin de documenter l’acceptabilité sociale de l’intervention comportementale intensive

Early intensive behavioral intervention is more widely used in large-scale community-based services in Autism Spectrum Disorder. There is an increased need to evaluate the social acceptability of these programs. The present study used a measure of social acceptability as part of a social validation procedure to evaluate a community-based EIBI offered in inclusive childcare, as well as two focused interventions associated with this program. To do so, the Treatment Evaluation Inventory Short-form (TEI-SF) questionnaire was adapted and translated to French. The validation results for the TEI-SF, as well as for the social acceptability of the EIBI programs and procedures, are presented. The results are the first evidence of the validity of the TEI-SF (adapted and translated to French), presenting scores of validity of intervention and a favourable perspective related to the early intensive behavioral intervention and opening the door to further research.     

Emotional responses to behavioral economic incentives for health behavior change

Many people aim to change their lifestyle, but have trouble acting on their intentions. Behavioral economic incentives and related emotions can support commitment to personal health goals, but the related emotions remain unexplored. In a regret lottery, winners who do not attain their health goals do not get their prize but receive feedback on what their forgone earnings would have been. This counterfactual feedback should provoke anticipated regret and increase commitment to health goals. We explored which emotions were actually expected upon missing out on a prize due to unsuccessful weight loss and which incentive-characteristics influence their likelihood and intensity. Participants reported their expected emotional response after missing out on a prize in one of 12 randomly presented incentive-scenarios, which varied in incentive type, incentive size and deadline distance. Participants primarily reported feeling disappointment, followed by regret. Regret was expected most when losing a lottery prize (vs. a fixed incentive) and intensified with prize size. Multiple features of the participant and the lottery incentive increase the occurrence and intensity of regret. As such, our findings can be helpful in designing behavioral economic incentives that leverage emotions to support health behavior change.