Effective use of the blank comparison procedure in simple discrimination by infant capuchin monkeys: A methodological note.

In studies of simple and conditional discrimination, procedures are needed to measure those aspects of stimuli that control behavior. The blank comparison procedure is one such procedure. It was designed explicitly for assessing S+ and S- functions when discriminative stimuli are presented simultaneously.

Acquisition and maintenance of delayed matching-to-sample in tufted capuchin monkeys.

Delayed matching-to-sample (DMTS) is a commonly used procedure to investigate short-term memory. For the study of functions of forgetting, the delay between the disappearance of the sample stimulus and appearance of choices is manipulated. The intertrial interval (ITI) is also varied to assess interference effects.

Algorithmic analysis of relational learning processes in instructional technology: Some implications for basic, translational, and applied research.

A few noteworthy exceptions notwithstanding, quantitative analyses of relational learning are most often simple descriptive measures of study outcomes. For example, studies of stimulus equivalence have made much progress using measures such as percentage consistent with equivalence relations, discrimination ratio, and response latency. Although procedures may have ad hoc variations, they remain fairly similar across studies.

Stimulus control in a go/no-go procedure with compound stimuli with pigeons.

Our previous study using a go/no-go procedure with compound stimuli taught pigeons to peck at two-component compounds A1B1, A2B2, B1C1, B2C2 and refrain from pecking at A1B2, A2B1, B1C2, B2C1. Subjects showed training-consistent responding in tests presenting compounds rotated 180° (BA and CB relations) but not recombined (AC and CA relations). It is unclear whether the responses to BA and CB stimuli were controlled by the relation between the components (conditional discrimination) or by the compounds functioning as a unitary stimulus (simple discrimination).

Discrimination and Reversal Learning by Toddlers Aged 15-23 Months.

Few studies have investigated simple discrimination and discrimination reversal learning by children younger than 2 years. Extant research has shown that teaching discrimination reversals may be challenging with this population. We used social reinforcement and correction procedures to teach simple simultaneous discrimination and discrimination reversal tasks involving three pairs of animal pictures displayed in a paper notebook.

Generalized Identity Matching to Sample after Multiple-Exemplar Training in Capuchin Monkeys.

A multiple-exemplar identity matching-to-sample baseline was established to encourage development of generalized IDMTS performances in three adult male capuchins. Mask (blank comparison) or Shuffled S- procedures were used to promote (sample-S+) control in baseline relations and to assess stimulus control relations in generalized IDMTS tests. The IDMTS baseline comprised eight 3-stimulus sets or four 4-stimulus sets.

Blank-comparison matching-to-sample reveals a false positive symmetry test in a capuchin monkey.

A positive symmetry test result was obtained with a capuchin monkey that had previously exhibited virtually errorless AB and BA arbitrary matching-to-sample (MTS) with different stimuli. The symmetry test (BA) followed the acquisition of a new AB relation. It seemed possible, however, that the positive result could have occurred through the exclusion of previously defined comparison stimuli and not because the new AB and BA relations had the property of symmetry.

Controlling Relations in Stimulus Equivalence Classes of Preschool Children and Individuals with Down Syndrome.

We evaluated emergent stimulus-stimulus relations after two different training procedures. Participants were five typically developing preschool children and three individuals with Down Syndrome. Experiment 1 used two-comparison matching to sample (MTS) to establish AB and BC relations.

Rapid generation of balanced trial distributions for discrimination learning procedures: a technical note.

We describe novel computer algorithms for rapid, sometimes virtually instantaneous generation of trial sequences needed to instrument many behavioral research procedures. Implemented on typical desktop or laptop computers, the algorithms impose constraints to forestall development of undesired stimulus control by position, recent trial outcomes, and other variables that could impede simple and conditional discrimination learning. They yield trial-by-trial lists of sequences that can serve (1) as inputs to procedure control software or (2) in generating templates for constructing sessions for implementation by hand or machine.

Perceptual factors influence visual search for meaningful symbols in individuals with intellectual disabilities and Down syndrome or autism spectrum disorders.

Augmentative and alternative communication (AAC) systems often supplement oral communication for individuals with intellectual and communication disabilities. Research with preschoolers without disabilities has demonstrated that two visual-perceptual factors influence speed and/or accuracy of finding a target: the internal color and spatial organization of symbols. Twelve participants with Down syndrome and 12 with autism spectrum disorders (ASDs) completed two search tasks.

Eye-tracking measures reveal how changes in the design of aided AAC displays influence the efficiency of locating symbols by school-age children without disabilities.

PURPOSE Many individuals with communication impairments use aided augmentative and alternative communication (AAC) systems involving letters, words, or line drawings that rely on the visual modality. It seems reasonable to suggest that display design should incorporate information about how users attend to and process visual information. The organization of AAC symbols can influence the speed and accuracy with which children select a target symbol on a display.

Go/No-Go Procedure with Compound Stimuli: Effects of Training Structure On the Emergence of Equivalence Classes.

When the matching-to-sample (MTS) procedure is used, different training structures imply differences in the successive discriminations required in training and test conditions. When the go/no-go procedure with compound stimuli is used, however, differences in training structures do not imply such differences. This study assessed whether the go/no-go procedure with compound stimuli with different training structures would produce significant variations in emergent performances.

Non-Mendelian etiologic factors in neuropsychiatric illness: pleiotropy, epigenetics, and convergence.

The target article by Charney on behavior genetics/genomics discusses how numerous molecular factors can inform heritability estimations and genetic association studies. These factors find application in the search for genes for behavioral phenotypes, including neuropsychiatric disorders. We elaborate upon how single causal factors can generate multiple phenotypes, and discuss how multiple causal factors may converge on common neurodevelopmental mechanisms.

Restricted Stimulus Control in Stimulus Control Shaping with a Capuchin Monkey.

Teaching the first instances of arbitrary matching to sample to nonhumans can prove difficult and time consuming. Stimulus control relations may develop that differ from those intended by the experimenter - even when stimulus control shaping procedures are used. This paper reports efforts to identify sources of shaping program failure with a capuchin monkey.

Relational discrimination by pigeons in a go/no-go procedure with compound stimuli: a methodological note.

A go/no-go procedure with compound stimuli typically establishes emergent behavior that parallels in structure and typical outcome that of conventional tests for symmetric, transitive, and equivalence relations in normally capable adults. The present study employed a go/no-go compound stimulus procedure with pigeons. During training, pecks to two-component compounds A1B1, A2B2, B1C1, and B2C2 were followed by food.

Conditional Discriminations by Preverbal Children in an Identity Matching-to-Sample Task.

This study sought to develop methodology for assessing whether children aged 16-21 months could learn to match stimuli on the basis of physical identity in conditional discrimination procedures of the type routinely used in stimulus equivalence research with older participants. The study was conducted in a private room at a daycare center for children and toddlers. The child and the research sat together on the floor facing an apparatus with two windows.

Sample stimulus control shaping and restricted stimulus control in capuchin monkeys: a methodological note.

This paper reports use of sample stimulus control shaping procedures to teach arbitrary matching-to-sample to 2 capuchin monkeys (Cebus apella). The procedures started with identity matching-to-sample. During shaping, stimulus features of the sample were altered gradually, rendering samples and comparisons increasingly physically dissimilar.

Observing behavior and atypically restricted stimulus control.

Restricted stimulus control refers to discrimination learning with atypical limitations in the range of controlling stimuli or stimulus features. In the study reported here, 4 normally capable individuals and 10 individuals with intellectual disabilities (ID) performed two-sample delayed matching to sample. Sample-stimulus observing was recorded with an eye-tracking apparatus.

Recombinative reading derived from pseudoword instruction in a miniature linguistic system.

A miniature linguistic system was used to study acquisition of recombinative symbolic behavior. Three studies evaluated the teaching conditions of conditional discriminations with printed and spoken pseudowords that could potentially generate recombinative reading. Fifty-four college students across all studies learned to match 12 printed pseudowords to 12 spoken pseudowords.

Evaluation of resistance to change under different disrupter conditions in children with autism and severe intellectual disability.

Translational research inspired by behavioral momentum theory in the area of developmental disabilities has shown effects in individuals over a range of functioning levels. In the current study, behavioral momentum was assessed in 6 children diagnosed with autism and severe intellectual disability. In a repeated measures design, participants were exposed to relatively rich versus lean reinforcement contingencies in a multiple schedule with food reinforcers.

Behavioral Momentum: Translational Research in Intellectual and Developmental Disabilities.

Behavioral momentum theory (Nevin, 1992, Nevin & Grace, 2000) describes the relation between the characteristic level of reinforcement within a context and behavioral resistance to change within that context. This paper will describe the multiple-schedule-disrupter paradigm for basic behavioral momentum research and illustrate it with two representative examples from the literature with non-human subjects. The remainder of the paper will provide a review of translational research in human populations with intellectual and developmental disabilities (IDD) employing the multiple-schedule-disrupter paradigm and closely related variations.