Recent research on aetiology, development and phenomenology of self-injurious behaviour in people with intellectual disabilities: a systematic review and implications for treatment

Correlates of Impairment and Growth in Families of Young Autistic Children

The purpose of this project was to investigate potential correlates of family life impairment in families of young autistic children. This project incorporated measures of specific child and parent challenges in addition to a commonly used unidimensional measure of autism characteristics. In this way, we could assess whether such challenges explain variance in family life impairment, and whether their inclusion diminish associations between autism characteristics and family life impairment. Cross-sectional data were collected from 564 parents of autistic children aged 2 to 5 years who participated in a larger online study. Participants completed measures on child characteristics (autism characteristics, emotion dysregulation, speaking ability, flexibility, and sleep problems), parent depression, and family life impairment, using the Family Life Impairment Scale (FLIS). Multiple linear regression models were generated to examine whether any of the independent variables were associated with the four domains of the FLIS. Models controlled for child age and sex, parent education, and single-parent homes. All independent variables were associated with impairment in one or more FLIS domains. None of the primary independent variables were significantly associated with positive growth. More overt characteristics and behaviors (e.g., autism characteristics, reactivity, speaking ability, and flexibility) were associated with impairment in domains that reflected a family's ability to navigate the community. However, sleep challenges and parent and child emotional difficulties were most strongly associated with parent impairment. Findings suggests that families may have different needs across contexts and provide new avenues through which they might be better supported.

Chronic traumatic encephalopathy-neuropathologic change in a routine neuropathology service: 7-year follow-up

To follow our 2016 study of chronic traumatic encephalopathy neuropathologic change (CTE-NC) in our forensic autopsy service, we prospectively screened all cases with clinical histories of multiple concussions, persistent post-head injury symptoms, or ≥3 hospital investigations for head injuries from 2016 to 2022 inclusive using hyperphosphorylated tau (p-tau) immunostaining. The cases had routine brain sampling plus 4-6 additional lateral hemisphere samples. When "pathognomonic" CTE-NC lesions were identified, additional p-tau immunostaining was done for CTE-NC staging. Of ∼1100 adult brains aged 18-65 years examined, 85 were screened, and 16 were positive for CTE-NC (2 women, 14 men, ages 35-61 years, median 47 years). Alcohol abuse was documented in 14 of 16 (8 in combination with other substances); 5 had developmental brain anomalies (2 presumed genetic, 3 from acquired perinatal insults). Widespread p-tau deposits (high CTE-NC) were found in 7 of 16. Old brain contusions were present in 9 of 16, but CTE-NC did not colocalize. Of particular interest were (1) a man with FGFR3 mutation/hypochondroplasia and life-long head banging, (2) a woman with cerebral palsy and life-long head banging, and (3) a man with bilateral peri-Sylvian polymicrogyria, alcohol abuse, and multiple head injuries. Thus, CTE-NC occurs in association with repeated head trauma outside contact sports. Substance abuse is a common determinant of risk behavior. The utility of diagnosing mild-/low-stage CTE-NC in this population remains to be determined.

Professionals' attitudes towards people with intellectual disabilities who self-harm: A literature review

BACKGROUND

National Institute for Health and Care Excellence (NICE, 2013) Guidance on Self-Harm states that professionals supporting people who self-harm should demonstrate compassion, respect and dignity. This literature review examines the evidence for professionals' attitudes towards people with intellectual disabilities who self-harm.

METHOD

Four databases (PsychInfo, IBSS, CINAHL and Medline) were systematically searched to find relevant research since 2000.

RESULTS

Four studies met the criteria. Attitudes of professionals supporting people with intellectual disabilities are contrasted with those of professionals in settings focused on supporting people without intellectual disabilities. Professionals supporting people with intellectual disabilities tended to display attitudes and attributions reflective of biobehavioural and psychosocial theories of self-harm, with a greater emphasis on relationships.

CONCLUSION

Much more research is needed which examines the attitudes of professionals supporting people with intellectual disabilities who self-harm.

Pathophysiological Heterogeneity of the BBSOA Neurodevelopmental Syndrome

The formation and maturation of the human brain is regulated by highly coordinated developmental events, such as neural cell proliferation, migration and differentiation. Any impairment of these interconnected multi-factorial processes can affect brain structure and function and lead to distinctive neurodevelopmental disorders. Here, we review the pathophysiology of the Bosch–Boonstra–Schaaf Optic Atrophy Syndrome (BBSOAS; OMIM 615722; ORPHA 401777), a recently described monogenic neurodevelopmental syndrome caused by the haploinsufficiency of NR2F1 gene, a key transcriptional regulator of brain development. Although intellectual disability, developmental delay and visual impairment are arguably the most common symptoms affecting BBSOAS patients, multiple additional features are often reported, including epilepsy, autistic traits and hypotonia. The presence of specific symptoms and their variable level of severity might depend on still poorly characterized genotype–phenotype correlations. We begin with an overview of the several mutations of NR2F1 identified to date, then further focuses on the main pathological features of BBSOAS patients, providing evidence—whenever possible—for the existing genotype–phenotype correlations. On the clinical side, we lay out an up-to-date list of clinical examinations and therapeutic interventions recommended for children with BBSOAS. On the experimental side, we describe state-of-the-art in vivo and in vitro studies aiming at deciphering the role of mouse Nr2f1, in physiological conditions and in pathological contexts, underlying the BBSOAS features. Furthermore, by modeling distinct NR2F1 genetic alterations in terms of dimer formation and nuclear receptor binding efficiencies, we attempt to estimate the total amounts of functional NR2F1 acting in developing brain cells in normal and pathological conditions. Finally, using the NR2F1 gene and BBSOAS as a paradigm of monogenic rare neurodevelopmental disorder, we aim to set the path for future explorations of causative links between impaired brain development and the appearance of symptoms in human neurological syndromes.

Effects of Physical Exercise Interventions on Stereotyped Motor Behaviours in Children with ASD: A Meta-Analysis

Studies have reported that physical exercise reduces maladaptive stereotyped motor behaviours (SMB) in children with ASD, but these intervention studies vary in design and outcome. The present systematic review and meta-analysis included 22 studies, involving 274 children with ASD, to quantify the effect of exercise on SMB and its potential moderators. Multi-level modelling revealed a large overall effect, Hedges' g = 1.16, with significant heterogeneity across participant, treatment, and study levels. Further, a more appropriate model using between-case estimation for within-subject effects to improve comparability between single-case and group-design studies, yielded a smaller but still significant effect, g = 0.51. Lastly, higher exercise intensity, but not age, exercise duration or settings, reliably predicted treatment effectiveness. Implications for clinical practice and research are discussed.

Etiology and Management of Behavioral Disorder in Adults With Intellectual and Developmental Disabilities

Intellectual disability (ID) encompasses a wide variety of disorders that can severely affect an individual’s cognitive, social, emotional, and physical development, even when identified early in life. Initially, individuals with such disorders had shorter life expectancies. However, medical advances have increased the life expectancy of individuals with ID similar to that of the general population. More attention must be paid to manage diseases affecting the intellectually disabled elderly, such as diabetes, cardiovascular disease, chronic constipation, and behavioral disorders.

From Multisensory Assessment to Functional Interpretation of Social Behavioral Phenotype in Transgenic Mouse Models for Autism Spectrum Disorders

Autism spectrum disorder (ASD) is a common heterogeneous disorder, defined solely by the core behavioral characteristics, including impaired social interaction and restricted and repeated behavior. Although an increasing number of studies have been performed extensively, the neurobiological mechanisms underlying the core symptoms of ASD remain largely unknown. Transgenic mouse models provide a useful tool for evaluating genetic and neuronal mechanisms underlying ASD pathology, which are prerequisites for validating behavioral phenotypes that mimic the core symptoms of human ASD. The purpose of this review is to propose a better strategy for analyzing and interpreting social investigatory behaviors in transgenic mouse models of ASD. Mice are nocturnal, and employ multimodal processing mechanisms for social communicative behaviors, including those that involve olfactory and tactile senses. Most behavioral paradigms that have been developed for measuring a particular ASD-like behavior in mouse models, such as social recognition, preference, and discrimination tests, are based on the evaluation of distance-based investigatory behavior in response to social stimuli. This investigatory behavior in mice is regulated by multimodal processing involving with two different motives: first, an olfactory-based novelty assessment, and second, tactile-based social contact, in a temporally sequential manner. Accurate interpretation of investigatory behavior exhibited by test mice can be achieved by functional analysis of these multimodal, sequential behaviors, which will lead to a better understanding of the specific features of social deficits associated with ASD in transgenic mouse models, at high temporal and spatial resolutions.

The evolution of self-injurious behaviors in people with intellectual disability and epilepsy: A follow-up study

PURPOSE

Longitudinal studies of the evolution of Self-Injurious Behaviors (SIBs) in people with Intellectual Disability (ID) and epilepsy are not common. This study aimed to analyze the evolution (in terms of remission and persistence) and changes in the type, localization, frequency, and intensity of SIBs.

METHODS

SIBs were assessed in a sample of 52 people with ID and epilepsy, and re-evaluated after a seven-year interval, using the "Scale for the Assessment of Self-Injurious Behaviors". The scale was administered to caregivers (parents or health professionals) through a semi-structured interview conducted by a specifically trained psychologist.

RESULTS

The most frequent types of SIBs identified were: self-biting, self-hitting with objects, self-hitting with hand, object-finger in cavities. The main localizations of SIBs were: hands, mouth, head and cheeks. SIBs were found to be maintained after seven years, for type, localization, frequency, and intensity, in 90.4% of the sample. SIB types were stable over time, as were the affected areas. Global SIB frequency and intensity scores were found to be unchanged. Finally, a positive correlation was found between the frequency of SIBs and levels of intellectual disability. SIBs (frequency and intensity) and seizure frequency showed no correlation.

CONCLUSION

Given the negative impact of SIBs on the adaptation and quality of life of people with ID and epilepsy, we believe that further studies on biological, psychological and environmental aspects are needed in order to identify any potential factors that might explain the persistence of SIBs and to find effective interventions to reduce them.

Behavioral Approaches to Assessment and Early Intervention for Severe Problem Behavior in Intellectual and Developmental Disabilities

This article summarizes the literature on prevalence and establishment of severe problem behavior in individuals with intellectual and developmental disabilities, empirical support for applied behavior analysis, and evidence-based behavioral assessment and treatment procedures. Early intervention and prevention approaches and the role of the pediatrician with regard to surveillance, early intervention, and coordination of care are discussed.

Deficiency of SHANK3 isoforms impairs thermal hyperalgesia and dysregulates the expression of postsynaptic proteins in the spinal cord

SHANK3 is one of the scaffolding proteins in the postsynaptic density (PSD). Pain perception and underlying mechanisms were investigated in Shank3 exon 21 deficient (Shank3^△C) mice. Sixty-six mice were attributed according to their genotype to three groups: (1) wild-type (WT), (2) heterozygous Shank3^△C/+, and (3) homozygous Shank3^△C/△C. Complete Freund's adjuvant (CFA) was used to induce inflammatory pain, and thermal hyperalgesia was determined. CFA treatment reduced the thermal threshold in the WT group; groups expressing mutations of Shank3 (^△C/+ and ^△C/△C) had higher thresholds after CFA administration compared to the WT group. Mice with Shank3 mutations (^△C/+ or ^△C/△C) had a lower expression of GluN2A and IP₃R proteins and a higher expression of mGluR5 protein in the PSD compared to WT mice without changes in GluN1, GluN2B, and Homer expression. The crosslinking of Homer-IP₃R, but not Homer-mGluR5, was decreased in the total lysate. Deficit of Shank3 exon 21 may lead to impaired perception of thermal pain in mice under inflammatory conditions. This impairment may result from protein dysregulation in the PSD like downregulation of the GluN2A subunit, which may reduce NMDAR-mediated currents, and/or decreased crosslinking between Homer and IP₃R, which may reduce the release of Ca²⁺ from intracellular stores.

Management of Self-injurious Behaviors in Children with Neurodevelopmental Disorders: A Pharmacotherapy Overview

Neurodevelopmental disorders (NDDs), a group of disorders affecting ~1-2% of the general population, are caused by changes in brain development that result in behavioral and cognitive alterations, sensory and motor changes, and speech and language deficits. Neurodevelopmental disorders encompass a heterogeneous group of disorders including, but not limited to, Smith-Magenis syndrome, Lesch-Nyhan disease, cri du chat syndrome, Prader-Willi syndrome, pervasive developmental disorders, fragile X syndrome, Rett syndrome, Cornelia de Lange syndrome, and Down syndrome. Self-injurious behaviors (SIBs) are common in children with NDDs; depending on the specific NDD, the incidence of SIBs is nearly 100%. The management of SIBs in this population is complex, and little high-quality data exist to guide a consistent approach to therapy. However, managing SIBs is of the utmost importance for the child as well as the family and caregivers. Behavior therapies must be implemented as first-line therapy. If behavioral interventions alone fail, pharmacotherapy becomes an essential part of management plans. The limited available evidence for the use of common pharmacologic agents, such as second-generation antipsychotics, and less common agents, such as clonidine, n-acetylcysteine, riluzole, naltrexone, and topical anesthetics, is reviewed. Additional data from well-designed studies in children with NDDs are needed to gain a better understanding of this common and troublesome problem including efficacy and safety implications associated with pharmacotherapy. Until then, clinicians must rely on the limited available data, clinical expertise, and ongoing systematic monitoring when managing SIBs in children with NDDs.

Demonstration of Parent Training to Address Early Self-Injury in Young Children with Intellectual and Developmental Delays

Individuals with intellectual and developmental disabilities (IDD) are at a high risk for engaging in self-injurious behavior (SIB). Prognosis is poor when SIB emerges early. Limited research exists on interventions teaching parents how to manage their young child's SIB. This investigation assessed the feasibility of adapting an applied behavior analytic parent training program with 11 parents of children 1-5 years of age with IDD and SIB. Quantitative and observational measures were used to assess outcomes; semi-structured interviews assessed caregiver satisfaction. Outcomes yielded preliminary data suggesting the adapted curriculum was feasible and acceptable to parents. Initial efficacy outcomes yielded decreases in SIB and observed negative parent-child interactions on pre- and post-measures. Qualitative data provided areas for further curriculum refinement.

Mechanisms of Tactile Sensory Phenotypes in Autism: Current Understanding and Future Directions for Research

PURPOSE OF REVIEW

This review aims to summarize the current body of behavioral, physiological, and molecular knowledge concerning tactile sensitivity in autism spectrum disorder (ASD), with a focus on recent studies utilizing rodent models.

RECENT FINDINGS

Mice with mutations in the ASD-related genes, Shank3, Fmr1, UBE3A, and Mecp2, display tactile abnormalities. Some of these abnormalities appear to be caused by mutation-related changes in the PNS, as opposed to changes in the processing of touch stimuli in the CNS, as previously thought. There is also growing evidence suggesting that peripheral mechanisms may contribute to some of the core symptoms and common comorbidities of ASD. Researchers are therefore beginning to assess the therapeutic potential of targeting the PNS in treating some of the core symptoms of ASD. Sensory abnormalities are common in rodent models of ASD. There is growing evidence that sensory hypersensitivity, especially tactile sensitivity, may contribute to social deficits and other autism-related behaviors.

Risk Factors for Self-injurious Behavior in an Inpatient Psychiatric Sample of Children with Autism Spectrum Disorder: A Naturalistic Observation Study

Limited information about self-injurious behavior (SIB) is known for children and adolescents with Autism Spectrum Disorder (ASD) who require intensive behavioral health interventions. We examined risk-factors for SIB in 302 individuals with ASD (ages 4-20) admitted to six specialized psychiatric inpatient units. Seventy-four percent were reported by a caregiver to display SIB, however, only 25% were observed to engage in daily SIB during hospitalization. Those exhibiting SIB across environments had significantly higher ratings on caregiver questionnaires of SIB severity. Tree-structured classification was used to develop and validate two predictive models, one indicating which inpatient youth with ASD are likely to have SIB and a second indicating which individuals with SIB at home are likely to continue in an inpatient setting.

Altered Global mRNA Expressions of Pain and Aggression Related Genes in the Blood of Children with Autism Spectrum Disorders

Autism spectrum disorder (ASD) is characterized by repetitive stereotypic behaviors, restricted interests, social withdrawal, and communication deficits. Aggression and insensitivity to pain are largely unexplained in these cases. We analyzed nine mRNA expressions of the candidate genes related to aggression and insensitivity to pain in the peripheral blood of patients with ASD. Whole blood samples were obtained from 40 autistic patients (33 boys, 7 girls) and 50 age- and sex-matched controls (37 boys and 13 girls) to isolate RNA. Gene expression was assessed by quantitative Real-Time PCR (qRT-PCR) in the Erciyes University Genome and Stem Cell Center (GENKOK). All of the gene expressions except CRHR1 and SLC6A4 were found to be statistically different between the ASD patients and controls. Gene expression also differed according to gender. Alterations in the mRNA expression patterns of the HTR1E, OPRL1, OPRM1, TACR1, PRKG1, SCN9A and DRD4 genes provide further evidence for a relevant effect of the respective candidate genes on the pathophysiology of ASD. Future studies may determine the sensitivity of these candidate markers in larger samples including further neuropsychiatric diagnosis.

Risk factors and topographies for self-injurious behaviour in a sample of adults with intellectual developmental disorders

BACKGROUND

Self-injurious behaviour (SIB) is a prevalent form of challenging behaviour in people with intellectual developmental disorders (IDD). Existing research has yielded conflicting findings concerning the major risk factors involved, and in addition, SIB shows multiple topographies and presentations. Although presence of autism spectrum disorders (ASD) and severity of intellectual disability (ID) are known risk factors for SIB, there are no studies comparing SIB topographies by severity degrees of ID and ASD. The purpose of the present paper has been to identify risk factors and topographies for SIB in a representative, stratified and randomised sample of adults with IDD.

METHOD

This study was conducted on the basis of data collected by the POMONA-ESP project, in a sample of 833 adults with IDD. Data concerning demographic and health information, ASD symptoms, psychopathology and ID, have been analysed to determine the presence of risk factors for SIB among participants and to explore the occurrence and topographies of SIB across different severity levels of ID and ASD symptoms.

RESULTS

Self-injurious behaviour prevalence in the sample was 16.2%. Younger age, oral pain, greater severity of ID, presence of dual diagnosis, psychiatric medication intake and higher scores on Childhood Autism Rating Scale were risk factors for SIB among participants, whereas number of areas with functioning limitations, place of residence, diagnosis of epilepsy and sex were not. SIB was more frequent in participants with ASD symptoms regardless of its severity level, and they displayed a higher number of different topographies of SIB. People with profound ID without co-morbid ASD symptoms showed similar results concerning SIB prevalence and topographies.

CONCLUSIONS

Knowledge on risk factors and topographies of SIB might play a vital role in the development of prevention strategies and management of SIB in people with IDD. The mere presence of ASD symptoms, regardless of its severity level, can be a crucial factor to be taken into account in assessing SIB. Accordingly, the presence of SIB in people with ID, especially when presented with a varied number of topographies, might provide guidance on ASD differential diagnosis.

Classification of self-injurious behaviour across the continuum of relative environmental-biological influence

Self-injurious behaviour (SIB) is generally considered to be the product of interactions between dysfunction stemming from the primary developmental disability and experiences that occasion and reinforce SIB. As a result of these complex interactions, SIB presents as a heterogeneous problem. Recent research delineating subtypes of SIB that are nonsocially mediated, including one that is amenable to change and one that is highly invariant, enables classification of SIB across a broader continuum of relative environmental-biological influence. Directly examining how the functional classes of SIB differ has the potential to structure research, will improve our understanding this problem, and lead to more targeted behavioural and pharmacological interventions. Recognising that SIB is not a single entity but is composed of distinct functional classes would better align research with conceptual models that view SIB as the product of interactions between environmental and biological variables.

Treatment of severe problem behaviour in children with autism spectrum disorder and intellectual disabilities

Children with autism spectrum disorder (ASD) and intellectual disabilities (ID) present with problem behaviour at rates disproportionately higher than their typically-developing peers. Problem behaviour, such as self-injury, aggression, pica, disruption, and elopement result in a diminished quality-of-life for the individual and family. Applied behaviour analysis has a well-established research base, detailing a number of assessment and treatment methods designed to address behaviour problems in children with ASD and ID. Although the variables that lead to the emergence of problem behaviour are not precisely known, those that are currently responsible for the maintenance of these problems can be identified via functional behaviour assessment, which is designed to identify events that occasion problem behaviour, consequences that maintain it, as well as other environmental factors that exert influence on the behaviour. Corresponding function-based treatment is implemented when environmental determinants are identified, with the aim of decreasing or eliminating problem behaviour, as well as teaching the individual to engage in more appropriate, alternative behaviour. In some cases, when problem behaviour is under the control of both environmental and biological variables, including psychiatric conditions, combining behavioural and pharmacological interventions is viewed as optimal, although there is limited empirical support for integrating these approaches.

Self-Injurious Behavior in Children With Developmental Disabilities: A Systematic Review of Behavioral Intervention Literature

We reviewed single-case research studies examining the effects of behavioral interventions for self-injurious behavior (SIB) in young children with autism and developmental disabilities. Systematic searches of electronic databases, journals, and reference lists identified 46 studies (66 participants younger than the age of 12) meeting inclusion criteria. Studies were examined based on (a) participant demographics, (b) topography and function of SIB, (c) type of functional behavior assessment (FBA), (d) intervention procedures and outcomes, and (e) experimental design and measurement. Intervention strategies were categorized as antecedent manipulations, teaching behavior, consequence-based procedures, and/or extinction procedures. Positive outcomes were reported for 78% of participants in the reviewed studies and 88% of the participants were diagnosed with autism. Results suggest the effectiveness of behavioral interventions to decrease SIB for young children with disabilities; however, the frequent use of packaged interventions without component analysis limits the conclusiveness of any treatment recommendation. Suggestions for future research are discussed.

Potential Risk Factors for the Development of Self-Injurious Behavior among Infants at Risk for Autism Spectrum Disorder

Prevalence of self-injurious behavior (SIB) is as high as 50% among children with autism spectrum disorder (ASD). Identification of risk factors for the development of SIB is critical to early intervention and prevention. However, there is little empirical research utilizing a prospective design to identify early risk factors for SIB. The purpose of this study was to evaluate behavioral characteristics predicting SIB at age 2 years among 235 infants at high familial risk for ASD. Logistic regression results indicated that presence of SIB or proto-SIB and lower developmental functioning at age 12 months significantly predicted SIB at 24 months. A pattern of persistent SIB over this period was associated with a diagnosis of autism and poorer cognitive and adaptive outcomes.

Signalling changes to individuals who show resistance to change can reduce challenging behaviour

BACKGROUND & OBJECTIVES

Several neurodevelopmental disorders are associated with resistance to change and challenging behaviours - including temper outbursts - that ensue following changes to routines, plans or expectations (here, collectively: expectations). Here, a change signalling intervention was tested for proof of concept and potential practical effectiveness.

METHODS

Twelve individuals with Prader-Willi syndrome participated in researcher- and caregiver-led pairing of a distinctive visual-verbal signal with subsequent changes to expectations. Specific expectations for a planned subset of five participants were systematically observed in minimally manipulated natural environments. Nine caregivers completed a temper outburst diary during a four week baseline period and a two week signalling evaluation period.

RESULTS

Participants demonstrated consistently less temper outburst behaviour in the systematic observations when changes imposed to expectations were signalled, compared to when changes were not signalled. Four of the nine participants whose caregivers completed the behaviour diary demonstrated reliable reductions in temper outbursts between baseline and signalling evaluation.

LIMITATIONS

An active control group for the present initial evaluation of the signalling strategy using evidence from caregiver behaviour diaries was outside the scope of the present pilot study. Thus, findings cannot support the clinical efficacy of the present signalling approach.

CONCLUSIONS

Proof of concept evidence that reliable pairing of a distinctive cue with a subsequent change to expectation can reduce associated challenging behaviour is provided. Data provide additional support for the importance of specific practical steps in further evaluations of the change signalling approach.

SHANK3 Deficiency Impairs Heat Hyperalgesia and TRPV1 Signaling in Primary Sensory Neurons

Abnormal pain sensitivity is commonly associated with autism spectrum disorders (ASDs) and affects the life quality of ASD individuals. SHANK3 deficiency was implicated in ASD and pain dysregulation. Here, we report functional expression of SHANK3 in mouse dorsal root ganglion (DRG) sensory neurons and spinal cord presynaptic terminals. Homozygous and heterozygous Shank3 complete knockout (Δe4-22) results in impaired heat hyperalgesia in inflammatory and neuropathic pain. Specific deletion of Shank3 in Nav1.8-expressing sensory neurons also impairs heat hyperalgesia in homozygous and heterozygous mice. SHANK3 interacts with transient receptor potential subtype V1 (TRPV1) via Proline-rich region and regulates TRPV1 surface expression. Furthermore, capsaicin-induced spontaneous pain, inward currents in DRG neurons, and synaptic currents in spinal cord neurons are all reduced after Shank3 haploinsufficiency. Finally, partial knockdown of SHANK3 expression in human DRG neurons abrogates TRPV1 function. Our findings reveal a peripheral mechanism of SHANK3, which may underlie pain deficits in SHANK3-related ASDs.

Increased Exposure to Rigid Routines can Lead to Increased Challenging Behavior Following Changes to Those Routines

Several neurodevelopmental disorders are associated with preference for routine and challenging behavior following changes to routines. We examine individuals with Prader-Willi syndrome, who show elevated levels of this behavior, to better understand how previous experience of a routine can affect challenging behavior elicited by disruption to that routine. Play based challenges exposed 16 participants to routines, which were either adhered to or changed. Temper outburst behaviors, heart rate and movement were measured. As participants were exposed to routines for longer before a change (between 10 and 80 min; within participants), more temper outburst behaviors were elicited by changes. Increased emotional arousal was also elicited, which was indexed by heart rate increases not driven by movement. Further study will be important to understand whether current intervention approaches that limit exposure to changes, may benefit from the structured integration of flexibility to ensure that the opportunity for routine establishment is also limited.

Comparative analysis of self-injury in people with psychopathology or neurodevelopmental disorders

Self-injury is a complex and poorly understood behavior observed in people with psychopathology or neurodevelopmental disorders (NDD). Despite the differences in etiology and progression of these distinct disease domains, it is possible that overlapping molecular pathways underlie the expression of self-injurious behaviors (SIBs). This review outlines the similarities and differences at the behavioural and molecular level, where SIBs in both conditions may involve opioid, nucleoside, and dopamine signalling. These points of convergence have important implications for treatment and research of SIB in both populations.

Stereotyped behaviors predicting self-injurious behavior in individuals with intellectual disabilities

We examined the relation between stereotyped behavior and self-injurious behavior (SIB) for 1871 individuals with intellectual disabilities who had a score of >0 on the Behavior Problem Inventory (BPI-01; Rojahn et al., 2001). We report three main findings: First, structural equation modeling techniques (SEM) revealed that the BPI-01stereotyped behavior subscale scores predicted BPI-01 SIB subscale scores. Second, when stereotyped behavior was modeled as a predictor of SIB, mixture-modeling techniques revealed two groups of individuals: one in which stereotyped behavior was a strong, statistically significant predictor of SIB (69% of the sample), and another one in which stereotyped behavior was not a predictor of SIB (31%). Finally, two specific stereotyped behavior topographies (i.e., body rocking and yelling) were identified that significantly predicted five different SIB topographies (i.e., self-biting, head hitting, body hitting, self-pinching, and hair pulling). Results are discussed in terms of future research needed to identify bio-behavioral variables correlated with cases of SIB that can, and cannot, be predicted by the presence of stereotyped behavior.

The progression of severe behavior disorder in young children with intellectual and developmental disabilities

Behavior disorders, such as self-injurious, stereotypic, and aggressive behavior are common among individuals with intellectual or developmental disabilities. While we have learned much about those behaviors over the past few decades, longitudinal research that looks at developmental trajectory has been rare. This study was designed to examine the trajectory of these three forms of severe behavior disorders over a one year time period. The behaviors were measured on two dimensions: frequency of occurrence and severity. Participants were 160 infants and toddlers at risk for developmental delays in Lima, Peru. Using structural equation modeling, we found that the frequency of self-injury and stereotypic behavior and the severity of aggressive behavior remained stable over the 12-month period. Uni-directional structural models fit the data best for self-injurious and aggressive behavior (with frequency being a leading indicator of future severity of self-injury and severity being a leading indicator of future frequency for aggression). For stereotypic behavior, a cross-lagged autoregressive model fit the data best, with both dimensions of frequency and severity involved as leading indicators of each other. These models did not vary significantly across diagnostic groups, suggesting that toddlers exhibiting behavior disorders may be assisted with interventions that target the specific frequencies or severities of behaviors, regardless of diagnostic category.

Pain sensitivity and observer perception of pain in individuals with autistic spectrum disorder

The peer-reviewed literature investigating the relationship between pain expression and perception of pain in individuals with ASD is sparse. The aim of the present systematic PRIMSA review was twofold: first, to see what evidence there is for the widely held belief that individuals with ASD are insensitive to pain or have a high pain threshold in the peer-reviewed literature and, second, to examine whether individuals with ASD react or express pain differently. Fifteen studies investigating pain in individuals with ASD were identified. The case studies all reported pain insensitivity in individuals with ASD. However, the majority of the ten experimental studies reviewed indicate that the idea that individuals with ASD are pain insensitive needs to be challenged. The findings also highlight the strong possibility that not all children with ASD express their physical discomfort in the same way as a neurotypical child would (i.e., cry, moan, seek comfort, etc.) which may lead caregivers and the medical profession to interpret this as pain insensitivity or incorrectly lead them to believe that the child is in no pain. These results have important implications for the assessment and management of pain in children with ASD.