Examining the relationship between heart rate and problem behavior: a case study of severe skin picking in Prader-Willi syndrome

A Scoping Review of Research Evaluating Physiological Information for Individuals With Developmental Disabilities: Augmentative and Alternative Communication Research Considerations

PURPOSE

Today, an ever-increasing number of technological advancements are becoming mainstream. As the availability of technological innovations increases, so do opportunities for evaluating any benefits of those innovations in augmentative and alternative communication (AAC) research for individuals with developmental disabilities. One innovation that has become mainstream is the use of noninvasive wearable technology to provide physiological information (e.g., heart rate, skin conductance). Such information could be valuable in AAC research, but more information about its potential feasibility and utility is needed.

METHOD

A scoping review was conducted to review and report on existing research that has evaluated (a) physiological information as a communication intervention tool for individuals with developmental disabilities and (b) the relationship between physiological information from individuals with developmental disabilities and behavioral and/or environmental information in real time.

RESULTS

Results revealed that, while little communication intervention research has been completed, descriptive research demonstrates that physiological information from individuals with developmental disabilities gathered using wearable technology corresponds meaningfully to observable environmental and behavioral events.

CONCLUSIONS

Future AAC research incorporating wearable technology to gather physiological information is warranted. Such research could evaluate potential benefits such as preempting challenging behavior with communication opportunities, signaling readiness for language learning, indicating AAC feature preferences, and expanding methodological approaches.

Skin Picking in People with Prader-Willi Syndrome: Phenomenology and Management

Skin picking is highly prevalent in people with Prader-Willi syndrome (PWS). This study addressed the temporal (frequency, duration) and wider characteristics (e.g. type of skin picked, apparent motivations, or management strategies) of skin picking to inform intervention strategies. Nineteen parents/carers who observe skin picking shown by the person they care for completed a semi-structured interview. Results were consistent with previous research but advanced the field by finding that most participants picked skin with an imperfection and that parents/carers most commonly use distraction as a management strategy. Interventions that are behavioural, support emotion regulation and/ or are used in the typically developing population are therefore likely to be beneficial for future research.

Functional analysis and treatment of problem behavior exhibited by children with fragile X syndrome

The efficacy of function-based interventions for the treatment of severe problem behavior exhibited by individuals with intellectual and developmental disabilities (IDD) is well established. However, few studies have reported on behavioral interventions in fragile X syndrome (FXS) specifically. The present study is a consecutive case-series analysis that reports on functional analysis and treatment of problem behavior of nine children with FXS. Assessment findings were consistent with previous research indicating that among individuals with FXS, problem behavior is more commonly maintained by escape from demands and access to tangible items, relative to the broader population of individuals with IDD. Functional analysis-based behavioral interventions resulted in a mean reduction in problem behavior of 95.2% across the nine participants. Additionally, generalization of treatment effects from controlled clinical settings to home, school, and community was demonstrated. The current findings suggest that function-based behavioral interventions shown to be effective with the broader population of individuals with IDD are also effective for individuals with FXS. Our results in combination with those of previous studies describing functional analysis outcomes provide additional evidence for a unique functional behavioral phenotype for severe problem behavior in individuals with FXS. Implications of study findings for early intervention and prevention of problem behavior in children with FXS are discussed.

Neural correlates of self-injurious behavior in Prader-Willi syndrome

Individuals with Prader-Willi syndrome (PWS), a genetic disorder caused by mutations to the q11-13 region on chromosome 15, commonly show severe skin-picking behaviors that can cause open wounds and sores on the body. To our knowledge, however, no studies have examined the potential neural mechanisms underlying these behaviors. Seventeen individuals with PWS, aged 6-25 years, who showed severe skin-picking behaviors, were recruited and scanned on a 3T scanner. We used functional magnetic resonance imaging (fMRI) while episodes of skin picking were recorded on an MRI-safe video camera. Three participants displayed skin picking continuously throughout the scan, three participants did not display skin picking, and the data for one participant evidenced significant B0 inhomogeneity that could not be corrected. The data for the remaining 10 participants (six male, four female) who displayed a sufficient number of picking and nonpicking episodes were subjected to fMRI analysis. Results showed that regions involved in interoceptive, motor, attention, and somatosensory processing were activated during episodes of skin-picking behavior compared with nonpicking episodes. Scores obtained on the Self-Injury Trauma scale were significantly negatively correlated with mean activation within the right insula and left precentral gyrus. These data indicate that itch and pain processes appear to underlie skin-picking behaviors in PWS, suggesting that interoceptive disturbance may contribute to the severity and maintenance of abnormal skin-picking behaviors in PWS. Implications for treatments are discussed.

Cardiac autonomic regulation in autism and Fragile X syndrome: a review

Despite the significance of efforts to understand the biological basis of autism, progress in this area has been hindered, in part, by the considerable heterogeneity in the disorder. Fragile X syndrome (FXS), a monogenic condition associated with high risk for autism, may pave the way for the dissection of biological heterogeneity within idiopathic autism. This article adopts a cross-syndrome biomarker approach to evaluate potentially overlapping profiles of cardiac arousal dysregulation (and broader autonomic dysfunction) in autism and FXS. Approaches such as this, aimed at delineating shared mechanisms across genetic syndromes, hold great potential for improving diagnostic precision, promoting earlier identification, and uncovering key systems that can be targeted in pharmaceutical/behavioral interventions. Biomarker approaches may be vital to deconstructing complex psychiatric disorders and are currently promoted as such by major research initiatives such as the NIMH Research Domain Criteria (RDoC). Evidence reviewed here supports physiological dysregulation in a subset of individuals with autism, as evidenced by patterns of hyperarousal and dampened parasympathetic vagal tone that overlap with the well-documented physiological profile of FXS. Moreover, there is growing support for a link between aberrant cardiac activity and core deficits associated with autism, such as communication and social impairment. The delineation of physiological mechanisms common to autism and FXS could lend insight into relationships between genetic etiology and behavioral endstates, highlighting FMR1 as a potential candidate gene. Research gaps and potential pitfalls are discussed to inform timely, well-controlled biomarker research that will ultimately promote better diagnosis and treatment of autism and associated conditions.

Experimental functional analysis of severe skin-picking behavior in Prader-Willi syndrome

Skin picking is an extremely distressing and treatment resistant behavior commonly shown by individuals with Prader-Willi syndrome (PWS). However, with the exception of a limited number of published single-case and survey studies, little is known about the environmental determinants of skin picking in this population. In this study, functional analyses were conducted with thirteen individuals with PWS, aged 6-23 years, who engaged in severe skin-picking behavior. In addition to the conditions typically employed in a functional analysis (i.e., alone, attention, play, demand), we included an ignore condition to examine potential effects of stimulus control by the presence of an adult. Twelve participants engaged in skin picking during the functional analysis, with the highest levels occurring in the alone and ignore conditions for eight participants, suggesting that skin picking in these participants was maintained by automatic reinforcement. For the remaining four participants, an undifferentiated pattern of low-rate skin picking was observed across conditions. These data confirm previous studies indicating that skin picking in PWS may be maintained most often by automatically produced sensory consequences. There were no associations between demographic characteristics of the participants (e.g., sex, age, IQ or BMI) and levels of skin picking observed in the functional analysis. Additional investigations are needed to identify the nature of the sensory consequences produced during episodes of skin picking in PWS. Behavioral interventions designed to extinguish or compete with the potential sensory consequences arising from skin picking in PWS are also warranted.

An analysis of the topography, severity, potential sources of reinforcement, and treatments utilized for skin picking in Prader-Willi syndrome

We examined the topography, severity, potential sources of reinforcement, and treatments utilized for skin-picking behavior shown by individuals with Prader-Willi syndrome (PWS). The parents of 55 individuals with PWS, aged 6-25 years, were interviewed about their child's skin-picking behavior using the Self-Injury Trauma Scale (SIT; Iwata, Pace, Kissel, Nau, & Farber, 1990) and the Functional Analysis Screening Tool (FAST; Iwata, DeLeon, & Roscoe, 2013). Results showed that skin picking in PWS occurred on the extremities (i.e., arms, legs, hands, and feet) for 75% of cases and resulted in bodily injury for 83.7% cases. Skin picking posed a high risk to the individual concerned in 41.8% of cases. Automatic sensory stimulation was identified as a potential source of reinforcement in the majority of cases (52.7%) followed by access to social attention or preferred items (36.4%). Treatments utilized by parents were primarily behavioral strategies (56.3%) followed by basic first aid (54.5%). There were no differences in the topography, severity or potential source of reinforcement between those with the deletion (DEL) subtype and those with the uniparental disomy (UPD) subtype. Taken together, these data indicate that skin picking shown by individuals with PWS is a particularly severe and intractable behavioral issue that may be maintained by (as yet unknown) sensory consequences. Further studies to identify the determinants of skin picking in PWS are therefore needed. The implications for interventions are discussed.