Receptive identification is usually taught in matching-to-sample format, which entails the presentation of an auditory sample stimulus and several visual comparison stimuli in each trial. Conflicting recommendations exist regarding the order of stimulus presentation in matching-to-sample trials. The purpose of this study was to compare acquisition…

Purpose: Published data indicate nearly adultlike frequency discrimination in infants but large child -adult differences for school-age children. This study evaluated the role that differences in measurement procedures and stimuli may have played in the apparent nonmonotonicity. Frequency discrimination was assessed in preschoolers, young…

Human contingency learning studies were used to compare the predictions of configural and elemental theories. In two experiments, participants were required to learn which stimuli were associated with an increase in core temperature of a fictitious nuclear plant. Experiments investigated the rate at which a simple negative patterning…

In two experiments, we examined the disruptive effects of a "can't answer" response option (CARO) on equivalence formation. The first experiment was a systematic replication of Duarte, Eikeseth, Rosales-Ruiz, and Baer (1998), in which participants in a CARO group and a No-CARO group performed conditional discrimination tasks with…

This study evaluated an intervention package combining simple and conditional discrimination training and specific reinforcement for each stimulus class in teaching reading of simple words to individuals with intellectual disabilities. In conditional discrimination training, participants matched printed words and pictures to the recorded sounds…

Stimulus overselectivity is widely accepted as a stimulus control abnormality in autism spectrum disorders and subsets of other populations. Previous research has demonstrated a link between both chronological and mental age and overselectivity in typical development. However, the age at which children are developmentally ready to respond to…

An equivalence class is typically established when a subject is taught a set of interrelated conditional discriminations with physically unrelated stimuli and additional, untaught, conditional discriminations are then demonstrated. Interestingly, and perhaps counter-intuitively, the relations among the stimuli within such a class are not…

Variation in baseline controlling relations is suggested as one of the factors determining variability in stimulus equivalence outcomes. This study used single- comparison trials attempting to control such controlling relations. Four children learned AB, BC, and CD conditional discriminations, with 2 samples and 2 comparison stimuli. In Condition…

Stimulus over-selectivity refers to behavior being controlled by one element of the environment at the expense of other equally salient aspects of the environment. Four experiments trained and tested non-clinical participants on a two-component trial-and-error discrimination task to explore the effects of different training regimes on…

A linked perceptual class consists of two distinct perceptual classes, A' and B', the members of which have become related to each other. For example, a linked perceptual class might be composed of many pictures of a woman (one perceptual class) and the sounds of that woman's voice (the other perceptual class). In this case, any sound of the…

A shift in generalization gradients away from S+ and towards stimuli on the opposite end of the stimulus dimension from S- is a well established phenomenon in the laboratory, occurring with humans and nonhumans and with a wide range of stimuli. The phenomenon of gradient shifts has also been observed to have an analogous relationship to a variety…

Discrete trial teaching procedures have been demonstrated to be effective in teaching a variety of important skills for children with autism spectrum disorders (ASD). Although all discrete trial programs are based in the principles of applied behavior analysis, some variability exists between programs with regards to the precise teaching…

Eighteen undergraduates participated in studies designed to examine the factors that produce transfer of contextual functions to novel stimuli in second-order conditional discriminations. In Study 1, participants selected comparison B1 given sample A1 and comparison B2 given sample A2 in a matching-to-sample procedure. Contextual stimuli X1 or X2…

Two experiments investigated baseline reviews as a relevant variable in reorganization of equivalence classes. After formation of three 4-member classes, participants learned reversals of baseline conditional discriminations and expanded the classes to 5 members each. In Experiment 1, 4 students responded on equivalence probes without baseline…

This study measured the differential effects of simplified and typical verbal antecedents on acquisition of picture discriminations for four preschool children with autism. During baseline probes, participants emitted no correct selection responses to pictures of common stimuli during either simplified or typical verbal antecedent conditions.…