Rebirth of the Shriver Automated Teaching Laboratory

This article describes an updated version of an automated teaching laboratory (ATL) at the Eunice Kennedy Shriver Center at the University of Massachusetts Medical School

Exclusive Preference on Concurrent Schedules in Children with Autism Spectrum Disorder

Treatment programs often utilize positive consequences to establish, increase, or maintain behavior. Recently, Dube and McIlvane (2002) examined the sensitivity of individuals with neurodevelopmental disabilities to differences in the frequency and magnitude of reinforcing consequences. Six individuals were exposed to a concurrent-choice procedure during which each option was associated with a range of schedules differing in reinforcer frequency or magnitude. Data were analyzed in accordance with the generalized matching law (Baum, 1974) and the positive slopes of obtained matching functions indicated sensitivity to the programmed reinforcer disparities. In recent follow-up work, we have been using the methods of Dube and McIlvane (2002) to assess sensitivity to changes in reinforcer frequency in individuals at lower functioning levels. During pretraining, a number of our recent participants developed exclusive or near-exclusive stimulus preferences that have proven difficult to overcome. This “Research in Progress” report is intended to highlight this challenge, describe efforts to overcome it, and to report potentially promising remedial procedures

The Establishment of Auditory-Visual Equivalence Classes with a Go/No-Go Successive Matching-to-Sample Procedure

The current study evaluated the effectiveness of a go/no-go successive matching-to-sample procedure (S-MTS) to establish auditory–visual equivalence classes with college students. A sample and a comparison were presented, one at a time, in the same location. During training, after an auditory stimulus was presented, a green box appeared in the center of the screen for participants to touch to produce the comparison. Touching the visual comparison that was related to the auditory sample (e.g., A1B1) produced points, while touching or refraining from touching an unrelated comparison (e.g., A1B2) produced no consequences. Following AB/AC training, participants were tested on untrained relations (i.e., BA/CA and BC/CB), as well as tacting and sorting. During BA/CA relations tests, after touching the visual sample, the auditory stimulus was presented along with a white box for participants to respond. During BC/CB relations tests, after touching the visual sample, a visual comparison appeared. Across 2 experiments, all participants met emergence criterion for untrained relations and for sorting. Additionally, 14 out of 24 participants tacted all visual stimuli correctly. Results suggest the auditory– visual S-MTS procedure is an effective alternative to simultaneous MTS for establishing conditional relations and auditory-visual equivalence classes

A FORMAÇÃO DE CLASSES DE EQUIVALÊNCIA VIA PAREAMENTO POR IDENTIDADE E DISCRIMINAÇÃO SIMPLES COM CONSEQÜÊNCIAS ESPECÍFICAS PARA AS CLASSES

Human participant performances often show evidence of learning untrained relations when conditional discrimination training between physically dissimilar stimuli is conducted. These emergent relations document equivalence class formation. The current study investigated whether class-specific consequences (i.e. the specific reinforcers used for each potential class during training) also join the equivalence class. Several studies have suggested they do so. However, training in those studies typically included arbitrary matching and identity matching baselines. In the current study, two autistic children were trained on simple discrimination reversals and identity matching with class specific consequences. They were then given arbitrary matching probes. Performances of both children initially showed evidence of class formation on these tests, despite the fact that neither had received training on arbitrary matching. In addition, one of the participants showed evidence of class formation after simple discrimination reversal training alone. These results demonstrate that the reinforcing consequences do in fact become part of the stimulus equivalence class and provide support for the ideas that equivalence (1) arises from reinforcement contingency and (2) is not based upon language skills. Key words: Stimulus equivalence, matching to sample, simple discrimination, outcome-specific reinforcement,differential outcomes effect, mental retardationO desempenho de participantes humanos freqüentemente mostra aprendizagem de relações não diretamente ensinadas após o treino de discriminações condicionais entre estímulos fisicamente diferentes. Essas relações emergentes documentam a formação de classes de equivalência. O presente estudo investigou se conseqüências específicas paras as classes (i.e., reforçadores específicos usados para cada classe potencial durante o treino) também integram as classes de equivalência. Vários estudos anteriores sugeriram que as conseqüências específicas podem integrar as classes, entretanto, o treino nesses estudos inclui pareamento arbitrário e pareamento por identidade. No presente estudo, duas crianças autistas foram submetidas apenas a treino de reversões de discriminações simples e pareamento por identidade com conseqüências específicas paras as classes potenciais. Então, testes de pareamento arbitrário foram conduzidos. O desempenho das crianças evidenciou a formação de classes nestes testes, a despeito de elas não terem experiência de treino de pareamento arbitrário. Adicionalmente, um dos participantes mostrou evidência de formação de classes após treino de reversões de discriminação simples somente. Esses resultados tanto demonstram que as conseqüências reforçadoras de fato se tornam parte das classes de equivalência, quanto dão suporte à idéia de que equivalência surge das contingências de reforçamento e não é baseada em habilidades lingüísticas. Palavras-chave: equivalência de estímulos, pareamento ao modelo, discriminação simples, reforçamento específico, efeito de conseqüência específica, retardo menta

Equivalence class formation via identity matching to sample and simple discrimination with class-specific consequences

Human participant performances often show evidence of learning untrained relations when conditional discrimination training between physically dissimilar stimuli is conducted. These emergent relations document equivalence class formation. The current study investigated whether class-specific consequences (i.e. the specific reinforcers used for each potential class during training) also join the equivalence class. Several studies have suggested they do so. However, training in those studies typically included arbitrary matching and identity matching baselines. In the current study, two autistic children were trained on simple discrimination reversals and identity matching with class specific consequences. They were then given arbitrary matching probes. Performances of both children initially showed evidence of class formation on these tests, despite the fact that neither had received training on arbitrary matching. In addition, one of the participants showed evidence of class formation after simple discrimination reversal training alone. These results demonstrate that the reinforcing consequences do in fact become part of the stimulus equivalence class and provide support for the ideas that equivalence (1) arises from reinforcement contingency and (2) is not based upon language skills

Reciprocity With Unequal Payoffs: Cooperative and Uncooperative Interactions Affect Disadvantageous Inequity Aversion

Cooperation among unrelated individuals can evolve through reciprocity. Reciprocal cooperation is the process in which lasting social interactions provide the opportunity to learn about others\u27 behavior, and to further predict the outcome of future encounters. Lasting social interactions may also decrease aversion to unequal distribution of gains – when individuals accept inequity payoffs knowing about the possibility of future encounters. Thus, reciprocal cooperation and aversion to inequity can be complementary phenomena. The present study investigated the effects of cooperative and uncooperative interactions on participants\u27 aversion to disadvantageous inequity. Participants played an experimental task in the presence of a confederate who acted as a second participant. In reality, the participant interacted with a computer programed to make cooperative and uncooperative choices. After interacting with a cooperative or uncooperative computer, participants chose between blue cards to produce larger gains to the computer and smaller for him/her or green cards to produce equal and smaller gains for both. Results confirmed our first hypothesis that uncooperative interactions would produce aversion to disadvantageous inequity. Lastly, half of the participants were informed that points received during the experiment could be later exchanged for money, and half were not. Results indicated that information about monetary outcomes did not affect aversion to inequity, contradicting our second hypothesis. We discuss these results in the light of theories of reciprocal cooperation, inequity aversion, and conformity

Learning of Equivalence Classes

Discusses the formation and learning processes for stimulance equivalence classes

The search for symmetry: 25 years in review

It has been 25 years since the publication of Sidman et al.\u27s (1982) report on the search for symmetry in nonhuman animals. They attributed their nonhuman subjects\u27 failure to the absence of some critical experiences (e.g., exemplar training, control of location variables, and generalized identity matching). Since then, species ranging from rats to chimpanzees have been tested on symmetry, and the results have been equivocal. Twenty-four investigations of symmetry in nonhumans are reviewed to determine whether the underlying factors first addressed by Sidman et al. (1982) have been verified and whether new factors have been identified. The emergent picture shows that the standard procedures as typically implemented on a three-key apparatus are insufficient by themselves to produce emergent symmetry in nonhumans. Recent successful demonstrations of symmetry in sea lions and pigeons have clarified certain important stimulus control variables (i.e., select and reject control) and suggest avenues for future research. Reliable symmetry may be achievable with nonhumans if training and test procedures that encourage compatible stimulus-control topographies and relations are designed

An Update on the Search for Symmetry in Nonhumans

Sidman et al.\u27s (1982) failure to find evidence for symmetry (bidirectional associations between stimuli) in monkeys and baboons set the stage for decades of work on emergent relations in nonhumans. They attributed the failure to the use of procedures that did not (1) promote stimulus control based on the relation between the sample and correct comparison and (2) reduce control by irrelevant stimulus features. Previous reviews of symmetry in nonhumans indicated that multiple exemplar training and successive matching might encourage appropriate stimulus control. This review examined 16 studies that investigated symmetry in 94 subjects, including pigeons, rats, capuchin monkeys, and baboons. Several studies used alternative training procedures to minimize sources of irrelevant stimulus control, and many combined multiple exemplar training with other procedural modifications. Symmetry was observed in approximately 30% of subjects. Studies that reported the strongest evidence for symmetry used successive matching‐to‐sample procedures that included training on both symbolic and identity relations, and studies finding mixed evidence employed alternative methods. These studies highlight the challenge in creating training procedures that promote symmetry and the need to assess the underlying sources of control on positive demonstrations