Stimulus-equivalence

Equivalence classes are defined according to the substitutability, or functional similarity, of the stimuli within a stimulus class. Several studies have demonstrated that the degree of functional similarity between stimuli in a class is dependent, in part, upon the number of nodes (intervening stimuli) between the stimuli. Higher nodal number is related to lower functional similarity. This effect is referred to as "nodality." There are three key factors that have not been simultaneously controlled for in the relevant studies: priming effects, reinforcement during training, and multiple stimulus functions of stimuli (sample, comparison, or both)...

The use of two choices in the matching-to-sample (MTS) procedure has been discouraged in the literature because it may lead to "reject control," resulting in failures to establish equivalence classes. In the present study, reject control was prevented during training with the two-choice MTS procedure by presenting the correct comparison with one of five possible incorrect comparisons across trials. This procedure was compared to a six-choice MTS procedure, in which these same six comparison stimuli were presented simultaneously across trials...

While humans exposed to a sequential stimulus pairing A-B are commonly assumed to form a bidirectional mental relation between A and B, evidence that non-human animals can do so is limited. Careful examination of the animal literature suggests possible improvements in the test procedures used to probe such effects, notably measuring transfer effects on the learning of B-A pairings, rather than direct recall of A upon cuing with B. We developed such an experimental design and tested 20 Guinea baboons (Papio papio)...

If one of several stimuli in an equivalence class acquires a function, it transfers to all members of the respective class. Even though research has demonstrated this transfer across a variety of stimulus functions (e.g., discriminative), few studies have focused on the transfer of the reinforcing function. The current study extended previous literature by establishing derived reinforcers using conditional discrimination training with six neurotypical adults. We established three 4-member equivalence classes and then created a discriminative stimulus in one member by correlating it with reinforcement...

Peer-mediated instructional strategies (e.g., peer tutoring) have been effective at teaching academic responses in previous research. This study extended the literature by programming for inference-making, or derived relations. Across two experiments, researchers investigated the use of peer tutoring and inference-making to teach fraction-pictogram-percentage relations to 8 third-grade participants. In each experiment, participants served as both tutors and tutees in homogenous, reciprocal tutoring sessions...

Equivalence class formation has been difficult to demonstrate in nonhumans, but one method that has been successful is a simple discrimination procedure in which contingencies associated with two sets of arbitrary discriminative stimuli are repeatedly reversed. Pigeons and sea lions shift responding after encountering the newly-reversed contingency with only a few set members, showing evidence of functional equivalence. We used this strategy to determine whether similar findings would occur in rats using olfactory stimuli...

The present experiments evaluated the effect of meaningful stimuli on the inclusion of a set of extra-experimental meaningful pictures into equivalence classes using within- and between-subjects designs. There were 35 adult participants in total (NEXP1 = 22; NEXP2 = 13). In both experiments, participants were first trained on 6 baseline relations with abstract stimuli (A, B, and C) and assessed on the emergence of three 3-member equivalence classes. Next, they were trained on DA relations and assessed on the inclusion of the D stimuli and a set of meaningful pictures in the equivalence classes...

In the present study, two typically developing 4-year-old children, Pete and Joe, were trained six conditional discriminations and tested for the formation of three 3-member equivalence classes. Pete and Joe did not establish the AC relation within 600 trials and were given two conditions of preliminary training, including naming of stimuli with two different stimulus sets. Pete started with preliminary training with common naming of stimuli, followed by conditional-discrimination training and testing for emergent relations, and continued with preliminary training on individual naming of stimuli, followed by the same training and testing as described previously...

BACKGROUND: The emergent categorization involving paintings by renowned painters and their corresponding names was demonstrated by previous studies. However, the results of these studies suggest that the colors of the pictures may have played a preponderant role, obscuring other aspects of the stimuli that could be more directly related to the style of each painter. To verify this possibility, the present study used the same methodology of Ferreira et al. to investigate the establishment of emergent conditional relations between categories composed of black and white paintings and the names of their authors...

From the 1930s to the 1970s a large number of experimental studies on mediated generalization were published, and this research tradition provided an important context for early research on stimulus equivalence. Mediated generalization and stimulus equivalence have several characteristics in common, notably that both traditions seek to experimentally investigate derived responding among arbitrarily related stimuli in human participants. Although studies of stimulus equivalence are currently being regularly published, few studies investigate mediated generalization in humans today, and the research tradition is mainly of historical interest...

The present study examined different conditions under which exclusion responding in conditional discrimination tasks would generate emergent equivalence relations in young children based on shared relationships with verbal labels. Both visual stimuli (Sets A, B, C, and D) and auditory stimuli (spoken words, Set N: N1 "correct"; N2: "incorrect") were used. Following a pilot study, three experiments were conducted, each involving eight preschool children. These experiments systematically investigated under which conditions responding by exclusion (i...

Tracking moment-to-moment change in input and detecting change sufficient to require altering behavior is crucial to survival. Here, we discuss how the brain evaluates change over time, focusing on the hippocampus and its role in tracking context. We leverage the anatomy and physiology of the hippocampal longitudinal axis, re-entrant loops, and amorphous networks to account for stimulus equivalence and the updating of an organism's sense of its context. Place cells have a central role in tracking contextual continuities and discontinuities across multiple scales, a capacity beyond current models of pattern separation and completion...

Sorting (SRT) and matching-to-sample (MTS) tests have measured the formation of arbitrary stimulus classes. This experiment used SRT and MTS tests to document the expansion of class size. Thirty-two participants learned 12 conditional discriminations with a linear series training structure (A➔B➔C➔D➔E). SRT tests documented the formation of 5-member classes by 17 of the participants. Thereafter, 6-member class expansion was implemented by FC training. Nine of these 17 participants showed class expansion when tracked with a sequence of an SRT, MTS, and a final SRT test, and the other 8 showed expansion when tracked with a sequence of MTS and SRT tests...

We sought to evaluate the efficacy of successive matching training for establishing generalized reflexive matching across 4 children with autism. In Experiment 1, differential reinforcement with delay fading was efficacious in establishing "yes" and "no" matching and nonmatching responses in 2 participants when 2 identical or nonidentical picture stimuli were presented. In addition, emergent visual-visual reflexive relational responses were observed using novel picture stimuli in a transfer test phase...

In behavior analysis, research on stimulus equivalence has been an area of high activity for more than 45 years. Murray Sidman's contribution was crucial in the development of this field, and, thus, it seems informative to highlight the experiments that were necessary in the development of the descriptive model of equivalence relations and behavior. The purpose of this paper is to provide an overview of the significant work that gave the historical context for Sidman and colleagues' conceptualization of stimulus equivalence as it was presented in 1982...

The study presented here investigated the effect of common and uncommon elements on class merger as predicted by Sidman in his reconceptualization of stimulus equivalence suggesting that common elements among contingencies can facilitate emergent performances (1994, 1997, 2000). Eight adult participants were exposed to a procedure that arranged for stimulus-reinforcer correlations in Phase 1 and response-reinforcer correlations in Phase 2 of a 3-phase study. In the common element group, the visual images serving as reinforcers were the same in Phase 1 and Phase 2...

Objectives : Investigate the physiological responses to active video games (AVG) in individuals with spinal cord injury by comparing oxygen consumption (VO2 ) and heart rate (HR) during an AVG session and at the ventilatory thresholds (i.e., anaerobic threshold and respiratory compensation point); and by calculating the session energy expenditure (EE). Method : Eight paraplegic individuals with spinal cord injury underwent cardiopulmonary exercise tests in an arm cycle ergometer to determine ventilatory thresholds...

Stimulus equivalence is defined as the ability to relate stimuli in novel ways after training in which not all of the stimuli had been directly linked to one another. Sidman (2000) suggested all elements of conditional discrimination training contingencies that result in equivalence potentially become class members. Research has demonstrated the inclusion of samples, comparisons, responses, and reinforcers in equivalence classes. Given the evidence that all elements of a conditional discrimination become part of the class, the purpose of this study was to determine if class-specific prompts would also enter into their relevant equivalence classes...

A reversal design was employed for the analysis of transfer of fear and avoidance through equivalence classes. Two 5-member equivalence classes (A1-B1-C1-D1-E1 and A2-B2-C2-D2-E2) were established. Then B1 and C1 were paired with shock (CS+) and served as SD s in avoidance training (B2 and C2 were trained as CS-/S∆ s for avoidance). Further avoidance training followed with D1 and E1 (as SD s) and D2 and E2 (as S∆ s), with the first presentation of each of these stimuli serving as the first transfer test...

The present study examined the effects of including stimuli previously trained as members of functional classes or equivalence classes on subsequent equivalence class formation, and isolated the effects of preliminary training from those of the acquired function stimuli. Fifty-six adults were assigned to 1 of 5 conditions. The control group (CONT) received no preliminary training prior to the terminal phase. Participants in the other 4 groups learned two 3-member functional classes and two 3-member equivalence classes during the preliminary phase...