The PEAK Relational Training Program has been recently published and favorable results for reliability and validity measures have been reported (Dixon, 2014). Results of two studies have demonstrated a high correlation with scores on the PEAK assessment scores, IQ scores as well as high reliability in scoring the PEAK assessments (Dixon, Carman, Tyler, Whiting, Enoch, & Daar, In press; Dixon, Whiting, Rowsey, & Belisle, In press). The current study evaluated normative data for Module 1 using 45 children ages 1 through 6 to validate it's utility in measuring the language of typically developing individuals. Normative data was collected and a strong positive correlation was identified between participants' age and PEAK assessment scores (r=.832, p=<.001). Implications support the use of PEAK to teach language and learning and continual investigation of its psychometric properties.

This study examined the development of social cognition in children with and without autism spectrum disorder (ASD), as well as the influence of behavioral and molecular genetics on these higher-order cognitive abilities. Specifically, it was hypothesized that children with ASD would perform more poorly on all social cognitive tasks compared with typically developing peers. In addition, it was hypothesized that typically developing children who performed better on a simpler social cognitive task at ages 3 or 4 would perform better at follow-up (i.e., one time between the ages of 6-10). Lastly, it was hypothesized that children who had at least one risk allele in both the DRD4 and the 5-HTTLPR polymorphisms would perform worse than those who had at least one risk allele in either polymorphism, who, in turn, would perform worse than children without any risk alleles. The twin sample included 62 families of multiples (twins, triplets, or quadruplets) who were recruited through the Southern Illinois Twins and Siblings Study (SITSS), and the ASD sample included 25 children who were recruited from the Center for Autism Spectrum Disorders at SIU. Significant group differences were found for children's performance on all of the social cognitive tasks. Furthermore, results showed that some areas of social cognition (theory of mind and the understanding of non-literal language) are more influenced by genetic factors than are other cognitive skills. Lastly, results from the molecular genetic analyses suggest that basic social cognitive skills (e.g., theory of mind) may be influenced by underlying biological factors in the serotonergic and dopaminergic pathways. The present study provided useful information on how psychological and genetic factors influence the development of social cognitive abilities in children with and without ASD.

The current set of experiments examined the utility of implementing the Promoting the Emergence of Advanced Knowledge (PEAK) Relational Training System (Dixon, 2014a, 2014b), an empirically validated assessment and intervention guide developed for children diagnosed with autism spectrum disorder (ASD), within Intensive Behavioral Intervention (IBI). Experiment 1 examined the relationship between scores on the commonly used Vineland Adaptive Behavior Scales Second Edition (VABS-II) (Sparrow, Cicchetto, & Balla, 2005) and scores on the PEAK Direct Training (PEAK-DT) (Dixon, 2014a) and PEAK Generalization (PEAK-G) (Dixon, 2014b) program assessments to examine additional psychometric properties suggesting the potential utility for use within IBI services. Experiment 2 examined the extent to which the PEAK manual (Dixon, 2014b) or additional staff training increased PEAK discrete trial training (DTT) procedural integrity of staff providing IBI to children diagnosed with ASD. Experiment 3 examined the effects of PEAK-G curriculum and instruction on the advanced language skills of children with ASD receiving IBI services. Results suggest that PEAK may be a valid assessment tool and effective intervention guide for use in IBI. Also, the manual and other effective staff training procedures (e.g., feedback, behavioral skills training) effectively enhance PEAK-G DTT procedural integrity. Lastly, the set of experiments in the current paper contributes to the dissemination of empirically based, behavior-analytic research that contributes to practical assessments and advanced interventions for children diagnosed with ASD. Specifically, PEAK-G enhances the language repertoires of children diagnosed with ASD through direct contingencies and programming for generalization across generalization gradients.

The present study investigates the language phenomenon of stimulus equivalence in children with Autism Spectrum Disorder. Stimulus equivalence is comprised of 3 main concepts: reflexivity, symmetry, and transitivity. Specifically, the researcher evaluated the ability to teach, test, and transfer sequential reflexivity across two participants. Two 4-year-old children diagnosed with Autism Spectrum Disorder participated in the study. Methods were derived from the program: Reflexivity: Pictures – 2A, along with a yes/no response modification to suite both of the participant’s current level of developmental skills. The results suggest that the PEAK-E curriculum was effective in training and testing both children to establish reflexivity across stimulus set one. In addition, both participants demonstrated a transfer of stimulus function to an untrained stimulus set two once the trained stimulus set one was mastered.

The increasing prevalence of Autism Spectrum Disorder has produced a longstanding relevance for continued progressive measures towards a systematic approach to the treatment of deficient language repertoires. Current behavior analytic assessments, such as the Assessment of Basic Language and Learning Skills-Revised (ABLLS-R), have demonstrated utility in providing relative measures of the functional characteristics of an individual’s language and learner repertoire, as consistent with a traditional Skinnerian approach. Further assessments have been created under other existing theoretical frameworks, such as the Test of Language Development (TOLD), and the Promoting the Emergence of Advanced Knowledge Relational Training System (PEAK). Each assessment was run with 17 children with Autism. A Spearman’s rank order correlation was then conducted to examine the relationships between the ABBLS-R, the TOLD-I:4, and PEAK-E-PA. Therefore, the purpose of the present investigation was to examine any existing relationships between these assessments in order to evaluate their treatment utility, produced measures, and overall implications towards an understanding of language development in children with Autism.

Autism spectrum disorder (ASD) is a pervasive lifelong developmental delay with a prevalence of 1 in 68 children. This growing epidemic occurs for unspecified causes and researchers continue to explore evidence-based treatments available. Parent–child interaction therapy (PCIT) is a parent training program, initially developed for implementation with typically-developing children. PCIT has shown effectiveness in increasing child compliance, minimizing disruptive problem, improving parent-child relationship satisfaction, and communication. The present study investigated the efficacy of PCIT as an evidence-based practice (EBP) for children with ASD by implementing a non-concurrent multiple baseline design across three participants. Results indicated socially significant increases in child compliance, decreases in aberrant behavior, rapid acquisition and maintenance of acquired parenting skills, as well as improved parent-child relationship satisfaction. This study aimed to replicate previous research measuring the effectiveness of PCIT with children with ASD.

Many children and adolescents with autism spectrum disorder (ASD) suffer from anxiety, depression, and other disorders. These disorders make it difficult to leave healthy and productive lives and can be experienced across school and social life. The mechanisms underlying anxiety and other disorders can be explained through language and cognition and this is the rational underlying Relational Frame Theory (RFT). RFT suggests that human language and cognition are a direct cause of many human psychological problems as we are able to evaluate words. The cognitive fusion, experiential avoidance, and suppression described by RFT have been expanded to include treatment methods within Acceptance and Commitment Therapy (ACT). ACT is a psychotherapeutic approach that attempts to undermine emotional avoidance explained through RFT and promotes positive behavior change. The purpose of the current study was to evaluate the efficacy of ACT in increasing value-directed behavior in three adults with ASD. The results of this study revealed that brief ACT experiential exercises were effective in increasing value-directed behavior in all participants. Keywords: Autism spectrum disorder (ASD), relational frame theory (RFT), Acceptance and commitment therapy (ACT)

Currently there is limited published literature on procedures for teaching distinction to individuals who are diagnosed with autism. The purpose of the current study was to evaluate the effectiveness of the procedures outlined within the PEAK T curriculum to teaching participants to respond in terms of the non-arbitrary property of distinction (i.e., “different”). The procedures that are described in the PEAK T program- 3D- Distinction: Picture Discrimination was replicated across three young males diagnosed with autism using a multiple exemplar simple discrimination training. Responding to non-arbitrary features of stimuli other than sameness is pivotal in the development of more complex forms of language. All three individuals achieved mastery criterion. The results continue to add to the need for research on the different frames of RFT.

Prisoners have high rates of physical and mental morbidity and of re-offending. There have been concerns that autism spectrum disorders (ASDs) may be overrepresented and under-diagnosed in this population. The aims of this study were to examine the effectiveness of an instrument which was developed to screen for ASDs in prisons and to establish whether male Scottish prisoners differ from community controls with respect to facial emotion recognition, as measured by behavioural testing, and differ on a neural basis while performing complex social judgements, as measured using functional magnetic resonance imaging (fMRI). A total of 2458 prisoners (approximately 40% of the convicted prison population) were examined using the screening tool, of whom a further 127 were interviewed in depth and were assessed for facial emotion recognition ability. FMRI was used to examine haemodynamic changes in a small sample of liberated prisoners (9) during a social judgement (approachability) versus control (gender judgments) task. The screening tool had poor sensitivity (28.6%) and specificity (75.6%) and was not effective or useful in screening for ASDs in this population. Significant deficits in negative facial emotion recognition were found in the prisoner group in comparison with age- and sex-matched community controls. Region of interest analysis of fMRI data in the bilateral amygdala revealed significantly greater activation in the left amygdala in ex-prisoners versus controls during the social judgement task. The identification of these abnormalities in facial emotion recognition and social judgement are in keeping with current literature on antisocial populations. They may offer the opportunity for development of interventions aimed at reducing re-offending in the future.

Intensive Behavioural Intervention (IBI) is one of the most widely used treatments for children with an autism spectrum disorder (ASD). While IBI has been recognized as the treatment of choice for very young children with an ASD, its sensible use among school age children is a matter of dispute. The aim of this thesis was to determine the clinical effectiveness of IBI, as compared with no treatment or treatment-as-usual, for the management of cognitive functioning and adaptive skills in preschool and school age children with an ASD, as well as to examine predictors of treatment response. Peer-reviewed, English language publications were identified using MEDLINE, EMBASE, PsychINFO, CINAHL, and ERIC from 1995 to September 1, 2014. Grey literature and reference lists of published papers were also searched for relevant records. Retrieved citations were screened by two independent reviewers, and data extraction was performed by a single reviewer with verification by a second reviewer. The methodological quality and procedural fidelity of included studies was assessed by one reviewer, and a subset of included studies were pooled in a random-effects meta-analysis using the standardized mean difference (SMD) effect size. A total of 24 unique studies were selected for inclusion in this review, comprising a total of 1,816 participants. Findings revealed that IBI improves full-scale IQ (SMD ES = 0.66, 95% CI 0.46 to 0.85, p<0.00001; 13 studies) and adaptive skills (SMD ES = 0.57, 95% CI 0.33 to 0.82, p<0.00001; 12 studies) in preschool and school age children with an ASD, with seemingly higher clinical benefits in children aged under 4 years at intake. Better outcomes with IBI are predicted by children’s relatively younger age, increased cognitive and adaptive ability, as well as a milder severity of symptoms at treatment entry. Results warrant careful interpretation in light of several methodological limitations and inadequate monitoring of procedural fidelity.