Stimulus Overselectivity Research Articles

Revaluation of overselected stimuli: Emergence of control by underselected stimuli depends on degree of overselectivity.

Stimulus overselectivity describes strong control by one stimulus element at the expense of other equally relevant elements. Research suggests that control by underselected stimuli emerges following extinction of the overselected stimulus ("revaluation") and the emergence is larger when overselectivity is greater. We compared such revaluation effects with a control compound or condition in two experiments. Human participants chose between compound S+ and S- stimuli. Then, to assess control by compound-stimulus elements, participants chose between individual elements in a testing phase without feedback. The S+ element chosen most often (the overselected element) underwent revaluation, during which choice of that element was extinguished and choice of a novel element reinforced. Thereafter, participants completed a retesting phase. Revaluation reduced choice of the overselected element. Choice of the underselected element decreased for participants with low overselectivity but increased for participants with high overselectivity. This was not the case for a control compound that did not undergo revaluation (Experiments 1 and 2) or in a control condition in which the overselected element continued to be reinforced during revaluation (Experiment 2). These findings suggest that overselectivity levels may modulate revaluation effects, and they also highlight the importance of the contingency change in postrevaluation changes in stimulus control.

Overselectivity during reading-related tasks for children at risk for reading failure

Stimulus overselectivity is defined as a learner’s performance coming under the control of a subset of elements in a compound stimulus. Research in this area has frequently included individuals with autism spectrum disorder, although overselectivity has also been shown in children and adults without developmental disabilities. In educational settings, textual stimuli serve as academically relevant compound stimuli made up of several elements (i.e., letters). The current study sought to identify potential overselective performances by five children at risk for reading failure when presented with 1-, 2-, or 3-element compound stimuli in a delayed matching-to-sample task. Stimuli were academically relevant targets presented in auditory (i.e., letter sounds or names) or visual (i.e., printed letters) modalities. Overall, stimulus overselectivity was more common during visual tasks and tasks that included compounds with three elements. These findings may inform interventions intended to remediate or prevent overselective performances in academic settings.

Cochran's Q Test of Stimulus Overselectivity within the Verbal Repertoire of Children with Autism.

Stimulus overselectivity remains an ill-defined concept within behavior analysis, because it can be difficult to distinguish truly restrictive stimulus control from random variation. Quantitative models of bias are useful, though perhaps limited in application. Over the last 50 years, research on stimulus overselectivity has developed a pattern of assessment and intervention repeatedly marred by methodological flaws. Here we argue that a molecular view of overselectivity, under which restricted stimulus control has heretofore been examined, is fundamentally insufficient for analyzing this phenomenon. Instead, we propose the use of the term "overselectivity" to define temporally extended patterns of restrictive stimulus control that have resulted in disproportionate populations of responding that cannot be attributed to chance alone, and highlight examples of overselectivity within the verbal behavior of children with autism spectrum disorder. Viewed as such, stimulus overselectivity lends itself to direct observation and measurement through the statistical analysis of single-subject data. In particular, we demonstrate the use of the Cochran Q test as a means of precisely quantifying stimulus overselectivity. We provide a tutorial on calculation, a model for interpretation, and a discussion of the implications for the use of Cochran's Q by clinicians and researchers.

Imagination in Autism: A Chance to Improve Early Language Therapy.

Children with autism often have difficulties in imaginative play, Theory of Mind, and playing out different scenarios in their minds. Research shows that the root of these problems may be the voluntary imagination network that involves the lateral prefrontal cortex and its long frontoposterior connections to the temporal-parietal-occipital area. Previously disconnected visuospatial issues (stimulus overselectivity and tunnel vision) and language issues (lack of comprehension of spatial prepositions and complex recursive sentences) may be explained by the same voluntary imagination deficit. This review highlights the new insights into the mechanism of voluntary imagination, its difference from involuntary imagination, and its unusually strong critical period. Clearer developmental terminology and a better understanding of voluntary imagination have the potential to facilitate communication between therapists and parents, and improve therapy outcomes in children.

Age effects on the development of stimulus over-selectivity are mediated by cognitive flexibility and selective attention

Stimulus over-selectivity is said to have occurred when only a limited subset of the total number of stimuli present during discrimination learning controls behavior, thus, restricting learning about the range, breadth, or all features of a stimulus. The current study investigated over-selectivity of 100 typically developing children, aged 3–7 (mean = 65.50 ± 17.31 SD months), using a visual discrimination task. Developmental trends in over-selectivity and their relationship to some cognitive variables (i.e., selective attention, sustained attention, and cognitive flexibility) were the target. Over-selectivity decreased with age, but this effect was mediated by the development of cognitive flexibility. Over-selectivity increased when a distractor task was introduced, which was not mediated by the other cognitive variables under investigation. The current results assist in the establishment of the theoretical underpinnings of over-selectivity by offering evidence of its underlying determinants and relating these to developmental trends.

Examination of Stimulus Over-Selectivity in Children With Autism Spectrum Disorder and Its Relationship to Stereotyped Behaviors and Cognitive Flexibility

Stimulus over-selectivity describes a phenomenon in which an individual responds only to a subset of the stimuli present in the environment and, thus, may restrict learning. This study aimed to develop understanding of the nature and role of over-selectivity in autism spectrum disorder (ASD) by analyzing the relationship of over-selectivity to core deficits of ASD: stereotyped responding and inflexibility. Over-selectivity was investigated in a visual discrimination task in 24 children, 12 diagnosed with ASD and 12 mental-age-matched typically developing children. In addition, the participants’ levels of intellectual functioning, stereotypy, and cognitive flexibility were assessed using established tools. Results showed that over-selectivity was associated with IQ and stereotyped behavior but was not related to levels of cognitive flexibility nor did cognitive flexibility significantly correlate with stereotyped behavior in individuals with ASD. The current findings require consideration when designing behavioral interventions for individuals with ASD.

Unpredictability reduces over-selective responding of individuals with ASD who have language impairments

Background: The phenomenon whereby behavior becomes controlled by one aspect of the environment at the expense of other equally-salient aspects of the environment (stimulus over-selectivity) is extremely common in many with Autism Spectrum Disorder (ASD). However, the theoretical mechanisms underpinning over-selectivity and its remediation are not well understood. Four experiments explored whether principles derived from associability accounts of learning, notably the concept of uncertainty, might allow better theoretical understanding of the phenomenon.Method: Participants with ASD who had language impairments received simultaneous discrimination training (AB+/CD−), and were tested in extinction regarding the degree to which the separate elements (A and B) of the previously reinforced compound (AB+) controlled behavior.Results: All experiments established the presence of over-selectivity; choosing one stimulus element to a greater-extent than the other. In Experiments 1 and 2, relative to a 100% feedback schedule, over-selectivity reduced when a 50%, but not a 25%, schedule of feedback was used. In Experiment 3, prolonged schedule exposure reduced over-selectivity. In Experiment 4, change from a 100% to a 33% schedule did not reduce over-selectivity.Conclusions: These results suggest that unpredictability, rather than variability per se, or reinforcement reduction and change, reduces over-selectivity. This suggests that attentional mechanisms, especially uncertainty, may play a role in this phenomenon during its acquisition and remediation.

Previous mindfulness experience interacts with brief mindfulness induction when reducing stimulus overselectivity

SummaryThe current study examined the effects of a brief mindfulness induction on overselectivity. Participants were randomly assigned to a mindfulness, unfocused attention (relaxation), or no‐intervention group. Participants experienced their designated intervention for 10 min, and they underwent simultaneous discrimination training (AB+ CD−) followed by an extinction test (AvC, AvD, BvC, and BvD). Levels of mindfulness were measured by the Toronto Mindfulness Scale, and participants were asked about their previous experience with mediation and mindfulness practice. Mindfulness reduced overselectivity, and previous levels of mindfulness experience identified by a single question moderated this effect, with mindful‐experienced participants showing less overselectivity. Both findings have some practical utility in the ongoing investigation of the possible use of mindfulness in medical settings.

The effect of stimulus duration on over-selectivity: Evidence for the role of within-compound associations.

The phenomenon whereby behavior becomes controlled by one aspect of the environment at the expense of other aspects of the environment (stimulus overselectivity) is widespread across many intellectual and developmental disabilities. However, the theoretical mechanisms underpinning overselectivity are not understood. Given similarities between overselectivity and overshadowing, exploring overselectivity using associative learning paradigms might allow better theoretical understanding of the phenomenon. Three experiments explored overselectivity using a simultaneous discrimination task with typically developing participants undergoing a cognitively demanding task. Experiment 1 investigated whether stimulus duration effects found within the overshadowing literature also occurred in an overselectivity paradigm, and demonstrated that greater overselectivity was observed when stimuli were presented for short durations (2s and 5s) compared with longer durations (10s). Experiment 2 demonstrated that a posttraining revaluation procedure resulted in retrospective revaluation for stimuli presented at shorter durations (2s) and mediated extinction for stimuli presented at longer durations (10s). Such results replicate findings from the overshadowing literature that have been interpreted in terms of within-compound associations while also supporting assumptions made by an extended comparator hypothesis. Experiment 3 uses an additional control condition to further demonstrate that the retrospective revaluation is a genuine revaluation effect. Additionally, the experiment provides further evidence for the within-compound association explanation of the results through manipulating the consistency with which elements of a compound were paired during training. Taken together, the findings highlight the necessity to consider the role of within-compound associations in overselectivity, allowing for a better understanding of overselectivity effects. (PsycINFO Database Record

Acquisition of Complex Conditional Discriminations in a Child with Autism Spectrum Disorder

Individuals diagnosed with autism spectrum disorder have been reported to demonstrate stimulus overselectivity or restricted stimulus control (i.e., failure to respond to all critical elements of complex stimuli). This potential may have a detrimental impact on the acquisition of academic skills for these individuals if the stimuli in question contain multiple controlling elements. The current study presents a number of methodologies by which attention to, and the subsequent control by, multiple elements of a complex stimulus was demonstrated. The participant in this study was a 10-year-old girl diagnosed with autism spectrum disorder. She was taught to select both printed word and picture comparisons, in the presence of complex sample stimuli comprised of visual and auditory elements, via an errorless learning protocol. Specifically, sample stimuli included manual American Sign Language (ASL) signs and the name of the sign. Following training, tests conducted in the absence of programed feedback verified accurate control by each sample element, as well as emergent stimulus-stimulus relations. No evidence of stimulus overselectivity was demonstrated during posttests. This study demonstrated an efficient methodology for forming stimulus classes through complex conditional discrimination training.

Factors producing over-selectivity in older individuals.

Stimulus over-selectivity describes a phenomenon where only a subset of the relevant stimuli present in the environment, control an individual's behavior. The current experiment explored the degree to which over-selectivity increases in old age. The level of over-selectivity in a visual discrimination task in 60 individuals aged 60-89years was assessed, as well as the degree to which this reflected attentional control. In addition, the intellectual functioning and cognitive flexibility of the participants were assessed. Results showed that, as age increased, three effects were revealed: levels of stimulus over-selectivity increased, IQ scores decreased, and cognitive flexibility decreased. However, over-selectivity was not related to IQ or cognitive flexibility, and appeared related most to attentional impairments. Thus, ageing is related to significant declines in effective stimulus control. These effects can have a serious impact on the physical and psychological health of old adults, as well as their quality of life, and, therefore, this area of research warrants further exploration. The results are discussed in relation to the attention-deficit and comparator theory of over-selectivity.

What Happened to Paul? Manifestation of Abnormal Pain Response for Individuals With Autism Spectrum Disorder.

During the progression of a pilot nutrition intervention designed to teach cooking skills to young adults with autism spectrum disorder (ASD), one participant-Paul-fell in the parking lot. Prior to the accident, Paul had been making significant gains in the program and had communicated in a number of ways his enthusiasm. After his accident, which resulted in broken and dislocated bones in his ankle, his demeanor was dramatically altered, program gains were lost, and staff noted the appearance of many new challenging behaviors. This article analyzes Paul's behavior in reference to the pain response in autism. For some time, it was believed that many individuals with ASD did not experience pain based on anecdotal reports of how individuals responded to injury with seeming indifference. This view has given way of late to a more nuanced understanding of how atypical sensory processing and stimulus over-selectivity spill over into pain pathways and pain amplification mechanisms. The consequence is not a reduction in pain sensation, but a different expression of pain, determined by that individual's particular communicative, cognitive, or physiological challenges. From this perspective, many of the disruptive and harmful behaviors that emerged after Paul's accident can be seen as a delayed response to the incident. This article concludes by arguing that professionals across all domains of health care need to begin to see behavior as communicative for those with ASD. This is particularly true of changes in behavior, which can be significant indicators of health care problems rather than something to be dismissed as another manifestation of the condition.

Stimulus over-selectivity and extinction-induced recovery of performance as a product of intellectual impairment and autism severity.

The current experiment investigated the extent to which three variables (autism severity, nonverbal intellectual functioning, and verbal intellectual functioning) are associated with over-selective responding in a group of children with Autism Spectrum Disorder. This paper also analyzed the association of these three variables with the recovery of responding to a previously under-selected stimulus following extinction of the previously over-selected stimulus. The results demonstrated that participants showed over-selectivity, and demonstrated that extinction of the over-selected stimulus led to recovery of responding to the previously under-selected stimulus. For both over-selectivity, and recovery from over-selectivity, verbal functioning appeared to predict the effects most strongly, with greater over-selectivity in the lower functioning individuals, and greater recovery in the higher functioning individuals.

Mental Imagery Therapy for Autism (MITA) - An Early Intervention Computerized Brain Training Program for Children with ASD

There is a broad consensus that early intervention has the greatest chance of positive impact on an individual with ASD. In this paper, we describe the development of an innovative computerized brain-training program for toddlers and preschoolers that has the potential to completely change their developmental trajectory. We describe the design of iPad-based game-like exercises that train a child to notice and respond to multiple cues. This ability is typically impaired in individuals with autism, leading to what is commonly described as stimulus overselectivity, or tunnel vision. Improving the capacity to discern and to respond to multiple cues has been shown to reduce stimulus overselectivity subsequently leading to vast improvements in general learning. Our hypothesis is that regular, prolonged practice with such exercises will result not only in a greater ability to attend to multiple cues, but also in vast improvements in transfer tasks measuring visuospatial as well as communicative skills. We also aim to show that computerized brain-training that is based on evidence based therapies could be used to reduce the gap between the amount of therapy recommended for children with ASD and the amount they actually receive. Finally, we describe early indicators of game engagement and outline planned future work to test the games’ efficacy as a therapeutic tool.

Examination of the prevalence of stimulus overselectivity in children with ASD.

Many individuals with autism spectrum disorders (ASD) display stimulus overselectivity, wherein a subset of relevant components in a compound stimulus controls responding, which impairs discrimination learning. The original experimental research on stimulus overselectivity in ASD was conducted several decades ago; however, interventions for children with ASD now typically include programming to target conditional discriminations in ways that might minimize the prevalence of stimulus overselectivity. The present study assessed 42 children who had been diagnosed or educationally identified with ASD using a discrimination learning assessment. Of these 42 children, 19% displayed overselective responding, which is a lower percentage than that seen in early research. Possible explanations for this decreased percentage, implications for intervention, and future directions for research are discussed.

The Potential Influence of Stimulus Overselectivity in AAC: Information from Eye Tracking and Behavioral Studies of Attention with Individuals with Intellectual Disabilities

This paper examines the phenomenon of stimulus overselectivity, or overselective attention, as it may impact AAC training and use in individuals with intellectual disabilities. Stimulus overselectivity is defined as an atypical limitation in the number of stimuli or stimulus features within an image that are attended to and subsequently learned. Within AAC, the term stimulus could refer to symbols or line drawings on speech-generating devices, drawings or pictures on low-technology systems, and/or the elements within visual scene displays. In this context, overselective attention may result in unusual or uneven error patterns such as confusion between two symbols that share a single feature, or difficulties with transitioning between different types of hardware. We review some of the ways that overselective attention has been studied behaviorally. We then examine how eye tracking technology allows a glimpse into some of the behavioral characteristics of overselective attention. We describe an intervention approach, differential observing responses, that may reduce or eliminate overselectivity, and we consider this type of intervention as it relates to issues of relevance for AAC.

Stimulus over-selectivity in temporal brain injury: Mindfulness as a potential intervention

Objective: The current study aimed to investigate the impact of brief mindfulness training on the performance of a sample of patients with TBI in an over-selectivity task.Participants: Twenty-four patients who had suffered TBI and reported problems with focused or sustained attention.Method: The study was a between-subjects design (mindfulness intervention vs control) with difference between number of most and least chosen stimulus selections on an over-selectivity task as the dependent measure.Results: The results of this study indicated that stimulus over-selectivity was present in a group of patients with TBI. However, the level of emergent over-selectivity was significantly reduced by a mindfulness induction when compared to a no- intervention control group.Conclusions: The findings are discussed in terms of the efficacy of mindfulness training in reducing TBI-related cognitive deficits.

Stimulus Overselectivity in Typical Development: Implications for Teaching Children with Autism

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 discriminations involving simultaneous multiple cues has not been established. Thirty-seven typically developing preschoolers completed a task requiring response to simultaneous cues (color and shape) to establish the age at which typically developing children can successfully respond to multiple cues. Results demonstrate that typically developing children under 36months of age have difficulty responding to multiple cues. Implications for behavioral treatment for autism are discussed.

Effect of Observing-Response Procedures on Overselectivity in Individuals With Autism Spectrum Disorders

Stimulus overselectivity occurs when one aspect of the environment controls behavior at the expense of other equally salient aspects. Stimulus overselectivity can be reduced for some individuals with learning disabilities, if they engage in an observing response in which they point to, touch, or name each of the stimuli prior to selecting the one requested. To see whether this would apply to another population, a total of 55 participants with autism spectrum disorders (ASD) were trained on match-to-sample (MTS), or simple discrimination tasks, to determine whether overselectivity could be eliminated by using an observing response. MTS tasks were presented in a table-top format as well as on a computer. The observing-response procedure did not eliminate overselectivity for any of the participants, regardless of age, task, or format of presentation. These results are interpreted to call to question the effectiveness of this procedure in this context for individuals with ASD.

Effect of a surprising downward shift in reinforcer value on stimulus over-selectivity in a simultaneous discrimination procedure

Stimulus over-selectivity refers to the phenomenon whereby behavior is controlled by a subset of elements in the environment at the expense of other equally salient aspects of the environment. The experiments explored whether this cue interference effect was reduced following a surprising downward shift in reinforcer value. Experiment 1 revealed that a downward shift in reinforcer value reduced over-selectivity in non-clinical adults under-taking a concurrent cognitive task. Experiments 2 and 3 ruled out a generalization decrement account of this effect; through manipulating the color of the stimuli across phases, we failed to find a reduction in over-selectivity, except for when the nature of the stimuli in one task changed in the context of another one that remained the same. Experiment 4 explored whether a reduction in over-selectivity is a function of the reinforcer and not the stimuli and failed to find a differential effect of reinforcer quality. Taken together, the results extend earlier findings of an attenuation of blocking following a surprise downward shift in reinforcer value to an over-selectivity paradigm in human subjects. Such work has important implications for remediation of over-selectivity.