Experimental functional analysis of aggression in children with Angelman syndrome

Association Between Challenging Behaviour and Sleep Problems in Adults Enrolled in the Global Angelman Syndrome Registry

Angelman Syndrome (AS) is a rare genetic disorder that impacts 1:20,000 people. Challenging behaviour, such as severe injurious behaviour, aggression and frequent unprovoked episodes of laughter are a significant problem among adults with AS that adversely impacts an individual's quality of life. This study, for the first time, aims understand the characteristic of challenging behaviour, its frequency, and the factors associated with it in adults with AS. Data from participants with AS (N = 37; aged 18-46 years) registered with the Global Angelman Registry, were divided into challenging behaviour and non-challenging behaviour groups based on the presence or absence of 50% of the behaviours recorded in the registry. Descriptive statistics, chi-squared and t-test analysis were conducted to assess the impact of variables on challenging behaviour. Multiple regressions were conducted to investigate the predictors of challenging behaviour. 56% of the sample presented with challenging behaviour. Disorders of arousal, self-injury, behaviour dysregulation, repetitive behaviour, and the lack of physical therapy accounted for 59% of the variance of challenging behaviour in this population. It was found that challenging behaviour was very common in this population. A significant association was found between challenging behaviour and both sleep arousal and the lack of physical therapy. Sleep arousal and the lack of physical therapy were the key factors associated with challenging behaviour in this study. Targeted interventions are needed to decrease challenging behaviour and future research should focus on sleep interventions and increased opportunities for physical therapy.

Current and emerging treatment options for Angelman syndrome

INTRODUCTION

Angelman syndrome (AS) is a neurodevelopmental disorder characterized by intellectual disability, limited expressive language, epilepsy, and motor impairment. Angelman syndrome is caused by haploinsufficiency of the UBE3A gene on the maternal copy of chromosome 15. There have been ongoing advances in the understanding of neurological, behavioral, and sleep-based problems and associated treatments for patients with AS. These results along with gene-based therapies entering into clinical development prompted this review.

AREAS COVERED

The authors summarize the research basis describing phenomenology of epilepsy and behavioral concerns such as hyperactivity behavior, aggression, self-injury, repetitive behavior, and sleep disorder. The evidence for recent treatment advances in these target symptom domains of concern is reviewed, and the potential for emerging gene therapy treatments is considered.

EXPERT OPINION

The prospect for emerging gene therapies means that increasing efforts should be directed toward the early identification of AS implemented equitably. Recent studies emphasize the important role of behavioral therapy in addressing mental health concerns such as aggression and disordered sleep.

Association between early and current gastro-intestinal symptoms and co-morbidities in children and adolescents with Angelman syndrome

BACKGROUND

Angelman syndrome (AS) is a neurogenetic disorder that causes severe intellectual disability, expressive language deficits, motor impairment, ataxia, sleep problems, epileptic seizures and a happy disposition. People with AS frequently experience gastrointestinal (GI) symptoms.

METHOD

This study used data from the Global Angelman Syndrome Registry to explore the relationship between early and current GI symptoms and co-morbidity in children and adolescents with AS (n = 173). Two groups that experienced a high (n = 91) and a low (n = 82) frequency of GI symptoms were examined in relation to feeding and GI history in infancy, sleep and toileting problems, levels of language and communication and challenging behaviours. Predictors of GI symptoms were then investigated using a series of logistic regressions.

RESULTS

This analysis found that constipation and gastroesophageal reflux affected 84% and 64%, of the sample, respectively. The high frequency of GI symptoms were significantly associated with: 'refusal to nurse', 'vomiting', 'arching', 'difficulty gaining weight', gastroesophageal reflux, 'solid food transition', frequency of night-time urinary continence and sleep hyperhidrosis during infancy. GI symptoms were not significantly associated with sleep, toileting, language or challenging behaviours. Significant predictors of high frequency GI symptoms were gastroesophageal reflux and sleep hyperhidrosis.

CONCLUSIONS

Future research needs to investigate the association between AS and GI co-morbidity in adults with AS.

Relationships between challenging behavior and gastrointestinal symptoms, sleep problems, and internalizing and externalizing symptoms in children and adolescents with Angelman syndrome

BACKGROUND

Angelman syndrome (AS), is a rare genetic disorder. This study investigated the relationship between parent-reported comorbid symptoms including gastrointestinal symptoms, sleep problems, internalizing symptoms, and behavior problems in children and adolescents with AS.

METHOD

Parents of 98 children and adolescents with AS completed the Gastrointestinal Symptom Inventory, Children's Sleep Habits Questionnaire, Child Behavior Checklist, Social Communication Questionnaire, and the Behavior Problem Inventory-Short Form. Data were analyzed using descriptive statistics, Pearson's correlation coefficients, and hierarchical multiple regressions.

RESULTS

There was a high frequency of GI symptoms (99%), sleep problems (95.9%), challenging behavior (98%), internalizing symptoms (38%), and 72.4% of children and adolescents presented with ASD symptoms. Self-injurious behavior (SIB), aggressive/destructive behavior, and the frequency of stereotyped behavior positively correlated with GI symptoms and sleep problems and it was moderately negatively associated with age. Internalizing symptoms and age were positively associated with SIB. Aggression was significantly related to gender, but not the presence of ASD symptoms.

CONCLUSIONS

Findings highlight the relationships between comorbid conditions. They may lead to a deeper understanding of how comorbidities present in children and adolescents with Angelman Syndrome.

A multidisciplinary approach and consensus statement to establish standards of care for Angelman syndrome

BACKGROUND

Angelman syndrome (AS) is a rare neurogenetic disorder present in approximately 1/12,000 individuals and characterized by developmental delay, cognitive impairment, motor dysfunction, seizures, gastrointestinal concerns, and abnormal electroencephalographic background. AS is caused by absent expression of the paternally imprinted gene UBE3A in the central nervous system. Disparities in the management of AS are a major problem in preparing for precision therapies and occur even in patients with access to experts and recognized clinics. AS patients receive care based on collective provider experience due to limited evidence-based literature. We present a consensus statement and comprehensive literature review that proposes a standard of care practices for the management of AS at a critical time when therapeutics to alter the natural history of the disease are on the horizon.

METHODS

We compiled the key recognized clinical features of AS based on consensus from a team of specialists managing patients with AS. Working groups were established to address each focus area with committees comprised of providers who manage >5 individuals. Committees developed management guidelines for their area of expertise. These were compiled into a final document to provide a framework for standardizing management. Evidence from the medical literature was also comprehensively reviewed.

RESULTS

Areas covered by working groups in the consensus document include genetics, developmental medicine, psychology, general health concerns, neurology (including movement disorders), sleep, psychiatry, orthopedics, ophthalmology, communication, early intervention and therapies, and caregiver health. Working groups created frameworks, including flowcharts and tables, to help with quick access for providers. Data from the literature were incorporated to ensure providers had review of experiential versus evidence-based care guidelines.

CONCLUSION

Standards of care in the management of AS are keys to ensure optimal care at a critical time when new disease-modifying therapies are emerging. This document is a framework for providers of all familiarity levels.

Parent Description of Anxiety in Angelman Syndrome

Anxiety is being increasingly identified in Angelman syndrome (AS). Qualitative questions and quantitative assessments were used to evaluate for anxiety in 50 subjects with AS. In-person evaluations assessed behaviors concerning for anxiety and circumstances wherein they occurred. Caregivers completed anxiety and other behavioral rating scales. Caregiver responses were categorized and compared to items from anxiety rating scales. The most common behavioral manifestation of anxiety was "aggression." The most common circumstance was "separation from caregiver/parent." Subjects had elevated scores on anxiety, irritability and hyperactivity scales with lower mean scores among subjects with a maternal deletion. The Pediatric Anxiety Rating Scale best captured behaviors described by caregivers. Existing anxiety scales should be adapted for use in AS.

Refining the Behavioral Phenotype of Angelman Syndrome: Examining Differences in Motivation for Social Contact Between Genetic Subgroups

Angelman syndrome (AS) is caused by loss of information from the 15q11.2-13 region on the maternal chromosome with striking phenotypic difference from Prader–Willi syndrome in which information is lost from the same region on the paternal chromosome. Motivation for social contact and sensory seeking behaviors are often noted as characteristics of the phenotype of AS and it has been argued that the strong drive for social contact supports a kinship theory interpretation of genomic imprinting. In this study we developed an experimental paradigm for quantifying the motivation for social contact in AS and examined differences across the genetic subtypes that cause AS [deletion, imprinting centre defect (ICD), uniparental disomy and UBE3A mutation]. Using single case experimental designs we examined the rate of acquisition of behavioral responses using operant learning paradigms for 21 children with AS whilst systematically varying the nature of social and sensory reinforcement. Variability in rates of acquisition was influenced by the nature of rewarding stimuli. Across the total sample both sensory stimuli and social contact could increase the rate of rewarded behavior with difference between children in the most effective reward. A striking difference in the rewarding properties of social contact across genetic subtypes was evidenced by non-deletion genetic causes of AS showing significantly higher rates of responding than the deletion cause in the social reinforcement paradigm. The results indicate that reinforcer assessment can beneficially inform behavioral interventions and that within syndrome variability in the behavioral phenotype of AS is likely driven by genetic difference. The non-deletion cause of AS, and particularly the ICD group, may be the optimal group for further study of genomic imprinting.

Aberrant aggressive behavior in a mouse model of Angelman syndrome

Angelman syndrome (AS) is a genetic neurodevelopmental disorder due to the absence of the E3-ligase protein, UBE3A. Inappropriate social interactions, usually hyper-sociability, is a part of that syndrome. In addition, clinical surveys and case reports describe aggressive behavior in AS individuals as a severe difficulty for caretakers. A mouse model for AS recapitulates most of the human AS phenotypes. However, very few studies utilized this mouse model for investigating affiliative social behavior, and not even a single study examined aggressive behavior. Hence, the aim of the herein study was to examine affiliative and aggressive social behavior. For that, we utilized a battery of behavioral paradigms, and performed detailed analyses of these behaviors. AS mice exhibited a unique characteristic of reduced habituation towards a social stimulus in comparison to their wild-type (WT) littermates. However, overall there were no additional marked differences in affiliative social behavior. In contrast to the mild changes in affiliative behavior, there was a striking enhanced aggression in the AS mice compared to their WT littermates. The herein findings emphasize the use of AS mouse model in characterizing and measuring inappropriate aggressive behavior, and suggests these as tools for investigating therapeutic interventions aimed at attenuating aggressive behavior.

Maladaptive behaviors in individuals with Angelman syndrome

Maladaptive behaviors are challenging and a source of stress for caregivers of individuals with Angelman Syndrome (AS). There is limited information on how these maladaptive behaviors vary over time among individuals with AS due to different genetic etiologies. In this study, caregivers of 301 individuals with AS were asked questions about their child's behavior and completed the Aberrant Behavior Checklist-Community version (ABC-C). Developmental functioning was evaluated with either the Bayley Scales of Infant Development, Third Edition (Bayley-III) or the Mullen Scales of Early Learning (MSEL). Family functioning was assessed using the parent-completed Parenting Stress Index (PSI) and the Family Quality of Life questionnaire (FQoL). Approximately 70% of participants had AS due to a deletion on the maternally-inherited copy of chromosome 15q11q13. Results revealed that at baseline, individuals with AS had low scores in the domains of lethargy (mean: 2.6-4.2 depending on genotype) and stereotypy (mean: 2.3-4.2 depending on genotype). Higher cognitive functioning was associated with increased irritability (r = 0.32, p < .01). Hyperactivity (p < .05) and irritability (p < .05) increased with age across all genotypes and should be ongoing targets for both behavioral and pharmacological treatment. Concerns for short attention span were endorsed by more than 70% of caregivers at baseline. Maladaptive behaviors, particularly hyperactivity, irritability and aggression, adversely affected parental stress, and family quality of life.

Using a Functional Analysis Followed by Differential Reinforcement and Extinction to Reduce Challenging Behaviors in Children With Smith-Magenis Syndrome

Smith-Magenis syndrome (SMS) is a genetic disorder, commonly caused by a 17p11.2 deletion, affecting the Retinoic Acid Induced 1 gene. It affects approximately 1 in 25,000 individuals, with over 90% engaging in challenging behaviors. Function-based treatments, using the principles of applied behavior analysis, have consistently been shown to decrease challenging behaviors exhibited by individuals with developmental delays. However, additional research is needed to determine the effects of these interventions with specific diagnostic subsets, including SMS. The current study identified the function of challenging behavior for 2 children with SMS and found a function-based treatment, consisting of differential reinforcement and extinction, reduced challenging behavior for both.

Unmet clinical needs and burden in Angelman syndrome: a review of the literature

Background

Angelman syndrome (AS) is a rare disorder with a relatively well-defined phenotype. Despite this, very little is known regarding the unmet clinical needs and burden of this condition, especially with regard to some of the most prevalent clinical features—movement disorders, communication impairments, behavior, and sleep.

Main text

A targeted literature review using electronic medical databases (e.g., PubMed) was conducted to identify recent studies focused on specific areas of the AS phenotype (motor, communication, behavior, sleep) as well as epidemiology, diagnostic processes, treatment, and burden. 142 articles were reviewed and summarized. Findings suggest significant impairment across the life span in all areas of function. While some issues may resolve as individuals get older (e.g., hyperactivity), others become worse (e.g., movement disorders, aggression, anxiety). There are no treatments focused on the underlying etiology, and the symptom-based therapies currently prescribed do not have much, if any, empirical support.

Conclusions

The lack of standardized treatment protocols or approved therapies, combined with the severity of the condition, results in high unmet clinical needs in the areas of motor functioning, communication, behavior, and sleep for individuals with AS and their families.

Intrafamily and intragenomic conflicts in human warfare

Recent years have seen an explosion of multidisciplinary interest in ancient human warfare. Theory has emphasized a key role for kin-selected cooperation, modulated by sex-specific demography, in explaining intergroup violence. However, conflicts of interest remain a relatively underexplored factor in the evolutionary-ecological study of warfare, with little consideration given to which parties influence the decision to go to war and how their motivations may differ. We develop a mathematical model to investigate the interplay between sex-specific demography and human warfare, showing that: the ecology of warfare drives the evolution of sex-biased dispersal; sex-biased dispersal modulates intrafamily and intragenomic conflicts in relation to warfare; intragenomic conflict drives parent-of-origin-specific patterns of gene expression-i.e. 'genomic imprinting'-in relation to warfare phenotypes; and an ecological perspective of conflicts at the levels of the gene, individual, and social group yields novel predictions as to pathologies associated with mutations and epimutations at loci underpinning human violence.

A Comparative Study of Sociability in Angelman, Cornelia de Lange, Fragile X, Down and Rubinstein Taybi Syndromes and Autism Spectrum Disorder

Few comparative studies have evaluated the heterogeneity of sociability across a range of neurodevelopmental disorders. The Sociability Questionnaire for People with Intellectual Disability (SQID) was completed by caregivers of individuals with Cornelia de Lange (n = 98), Angelman (n = 66), Fragile X (n = 142), Down (n = 117) and Rubinstein Taybi (n = 88) syndromes and autism spectrum disorder (ASD; n = 107). Between groups and age-band (<12yrs; 12-18yrs; >18yrs) comparisons of SQID scores were conducted. Rates of behaviors indicative of selective mutism were also examined. Fragile X syndrome achieved the lowest SQID scores. Cornelia de Lange, ASD, and Fragile X groups scored significantly lower than Angelman, Down and Rubinstein Taybi groups. Selective mutism characteristics were highest in Cornelia de Lange (40%) followed by Fragile X (17.8%) and ASD (18.2%). Age-band differences were identified in Cornelia de Lange and Down syndrome.

Parent stress across molecular subtypes of children with Angelman syndrome

BACKGROUND

Parenting stress has been consistently reported among parents of children with developmental disabilities. However, to date, no studies have investigated the impact of a molecular subtype of Angelman syndrome (AS) on parent stress, despite distinct phenotypic differences among subtypes.

METHOD

Data for 124 families of children with three subtypes of AS: class I and II deletions (n = 99), imprinting centre defects (IC defects; n = 11) and paternal uniparental disomy (UPD; n = 14) were drawn from the AS Rare Diseases Clinical Research Network (RDCRN) database and collected from five research sites across the Unites States. The AS study at the RDCRN gathered health information to understand how the syndrome develops and how to treat it. Parents completed questionnaires on their perceived psychological stress, the severity of children's aberrant behaviour and children's sleep patterns. Children's adaptive functioning and developmental levels were clinically evaluated.

RESULTS

Child-related stress reached clinical levels for 40% of parents of children with deletions, 100% for IC defects and 64.3% for UPD. Sleep difficulties were similar and elevated across subtypes. There were no differences between molecular subtypes for overall child and parent-related stress. However, results showed greater isolation and lack of perceived parenting skills for parents of children with UPD compared with deletions. Better overall cognition for children with deletions was significantly related to more child-related stress while their poorer adaptive functioning was associated with more child-related stress. For all three groups, the severity of children's inappropriate behaviour was positively related to different aspects of stress.

CONCLUSIONS

How parents react to stress depends, in part, on children's AS molecular subtype. Despite falling under the larger umbrella term of AS, it is important to acknowledge the unique aspects associated with children's molecular subtype. Identifying these factors can lead to tailored interventions that fit the particular needs of families of children with different AS subtypes.

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.

The neurobiology of aggression: implications for the pharmacotherapy of aggressive challenging behaviour by people with intellectual disabilities

AIM

The aim of this review is to summarise current understanding of the neurobiology of aggression and within this context to consider the evidence base for the pharmacotherapy of aggressive challenging behaviour by people with intellectual disabilities (ID).

EVIDENCE

Aggressive encounters involve a variety of psychological processes and progress has been made in understanding the brain mechanisms involved. However, the role in aggression of the neurotransmitters serotonin, dopamine and γ-aminobutyric acid is no longer as clear as it once appeared, with the result that predictions cannot be made with confidence about drug effects on aggression. There have been relatively few controlled trials of pharmacotherapy for aggression in people with ID, or, indeed, in the general population, and their outcomes have largely been negative.

CONCLUSION

With the possible exception of risperidone, there is no reliable evidence that antidepressant, neuroleptic or anticonvulsant drugs are effective treatments for aggression by people with ID.

The prevalence of aggression in genetic syndromes: a review

Research into behavioural phenotypes identifies both environmental and organic factors as influencing aggression in children and adults with genetic disorders associated with intellectual disability. However, in contrast to self-injury there is a paucity of research that compares aggression across relevant syndromes. The primary aim of this review is to examine the association between aggression and genetic syndromes by analysis of prevalence studies. The review also examines the literature on the form of the behaviour and influence of environmental factors. Results imply that certain syndrome groups (Cri du Chat, Smith-Magenis, Prader-Willi, Angelman, Cornelia de Lange, and Fragile X syndromes; estimates over 70%) evidence a stronger association with aggression than others (e.g. Williams and Down syndromes; estimates below 15%). However, the strength of association is difficult to quantify due to methodological differences between studies. The results from examining form and environmental influences highlight the importance of phenotype-environment interactions. Research employing group comparison designs is warranted and future work on the assessment and intervention of aggression in genetic syndromes should consider the importance of phenotype-environment interactions.

Correlates of self-injurious, aggressive and destructive behaviour in children under five who are at risk of developmental delay

AIM

Several behavioural correlates of self-injury, aggression and destructive behaviour have been identified in children and young adults with intellectual disabilities. This cross-sectional study aimed to further explore these correlates in very young children with developmental delay.

METHODS

Parents of 56 children (40 male) under the age of five years (mean age 2 years 10 months) completed a questionnaire about their child's behaviour and the presence of behavioural correlates, including repetitive, over-active or impulsive behaviour and more severe developmental delay.

RESULTS

Parents reported very high prevalence of self-injurious, aggressive and destructive behaviour: 51%, 64% and 51%, respectively. A binary logistic regression revealed that a higher score on a measure of overactive and impulsive behaviour significantly predicted the presence of destructive behaviour. A multiple linear regression revealed that both repetitive behaviour and number of health problems approached significance as independent predictors of severe self-injurious behaviour.

INTERPRETATION

Despite the very small sample, several factors emerged as potential predictors of self-injurious, aggressive and destructive behaviour. These findings support the need for further investigation in a larger sample. Confirmation in this age group could help guide the development of targeted early intervention for these behaviours by identifying behavioural risk markers.

The nature of social preference and interactions in Smith-Magenis syndrome

This natural observation study was designed to evaluate hypothesized elevated 'attention-seeking' and preference for adult attention in Smith-Magenis syndrome. Ten children with Smith-Magenis syndrome were observed across one school day, together with an age matched sample of 10 children with Down syndrome. Levels of attention given to, and vigilance for, adults and peers were recorded and compared. Sequences of behaviour were analyzed to evaluate the temporal relationships between giving and receiving attention during adult-child interactions. Compared to children with Down syndrome, children with Smith-Magenis syndrome gave preferential attention to adults and looked towards adults significantly more than they looked towards peers. Sequential analyses revealed that while children with Smith-Magenis syndrome did not initiate interactions with adults more than children with Down syndrome did, reciprocity between child and adult social behaviours in Smith-Magenis syndrome within interactions was compromised. This less synchronous sequence of child and adult interactions in Smith-Magenis syndrome may be the result of children with Smith-Magenis syndrome attempting to initiate interaction at times when it is unavailable. The marked preference for interacting with adults over peers in Smith-Magenis syndrome indicates atypicality of social interaction in this syndrome.

The motivating operation and negatively reinforced problem behavior: a systematic review

The concept of motivational operations exerts an increasing influence on the understanding and assessment of problem behavior in people with intellectual and developmental disability. In this systematic review of 59 methodologically robust studies of the influence of motivational operations in negative reinforcement paradigms in this population, we identify themes related to situational and biological variables that have implications for assessment, intervention, and further research. There is now good evidence that motivational operations of differing origins influence negatively reinforced problem behavior, and that these might be subject to manipulation to facilitate favorable outcomes. There is also good evidence that some biological variables warrant consideration in assessment procedures as they predispose the person's behavior to be influenced by specific motivational operations. The implications for assessment and intervention are made explicit with reference to variables that are open to manipulation or that require further research and conceptualization within causal models.

Discrimination training reduces high rate social approach behaviors in Angelman syndrome: proof of principle

This proof of principle study was designed to evaluate whether excessively high rates of social approach behaviors in children with Angelman syndrome (AS) can be modified using a multiple schedule design. Four children with AS were exposed to a multiple schedule arrangement, in which social reinforcement and extinction, cued using a novel stimulus, were alternated. Twenty-five to 35 discrimination training sessions were conducted and levels of approach behaviors were measured before and after the discrimination training for two children. All four participants evidenced discrimination between conditions of reinforcement and extinction after 16-20 teaching sessions as indicated by lower rates of social approach behaviors in the presence of the S(Δ) for extinction. Reversal effects for the two children for whom this design was implemented were evident. The results demonstrate that after repeated training, the use of a novel stimulus can serve as a cue for children with AS to discriminate adult availability. This is a potentially effective component of a broader intervention strategy but highlights the need for sustained teaching procedures within this population.

Functional analysis and functional communication training in individuals with Angelman syndrome

OBJECTIVE

To assess the functions of challenging behaviour in four children with Angelman syndrome (AS) and to study the effects of functional communication training (FCT) with precursor-based prompting. This study builds on and extends the study of Allen et al.

METHOD

Experimental functional analysis assessed behavioural functions. FCT was implemented within an ABAB design and effect sizes were calculated. Burst analyses depict tendencies in (precursor) behaviours surrounding target behaviours.

RESULTS

Results show challenging behaviour to be aimed at receiving attention, tangibles or escape. Burst analysis designated physical and eye contact and reaching for tangibles as precursors. Effects of FCT ranged from small to large.

CONCLUSION

Behavioural functions for challenging behaviour were found and FCT was effective in reducing its frequency, when precursors were used as the onset of prompting. Functional equivalence between challenging and communicative behaviour was found. Implementing treatment for challenging behaviour based on precursors is advised.

The occurrence of challenging behaviours in children with autism spectrum disorders and atypical development

OBJECTIVE

This study examines the occurrence of challenging behaviours in children with ASDs and atypical development.

DESIGN

This study is a descriptive non-experimental design that inspects the frequencies of challenging behaviours among two diagnostic groups. This type of methodology is important since research in this area is still in the beginning stages of development.

METHODS

The sample consisted of 2131 children, with 633 having an ASD and 1498 having atypical development. The Baby and Infant Screen for Children with aUtIsm Traits-Part 3 (BISCUIT-Part 3) assesses problematic behaviours within this population. The frequencies of challenging behaviours were examined along with an inspection of the co-occurring items.

RESULTS

Greater percentages of problematic behaviours were found in the ASD group as compared to the group with atypical development.

CONCLUSION

Challenging behaviours are variables affecting the behavioural presentation of those with ASDs and may be considered into the treatment plans for these children.

Age related change in social behavior in children with Angelman syndrome

We investigated the relationship between age and laughing and smiling in children with Angelman syndrome. Twenty-four children with Angelman syndrome were exposed to three experimentally manipulated conditions: proximity only, restricted social interaction, and social interaction. Children smiled the most in the social interaction condition and the least in the proximity only condition confirming the effect of social interaction on these behaviors. There was a decline in smiling and laughing in the oldest group (13.4-15.9 years) only in the social interaction condition. This trajectory of a decline in resource soliciting behaviors with age is consistent with predictions based on kinship theory.

Feeding Therapy in a Child With Autistic Disorder: Sequential Food Presentation

The authors describe a feeding intervention for a 9-year-old male diagnosed with autistic disorder and mild mental retardation (also known as intellectual disability) who experienced food refusal related to food selectivity. Based on the results of a functional behavioral assessment, food refusal was found to be maintained by escape and tangible functions. Therefore, an intervention using escape extinction (i.e., nonremoval of nonpreferred foods with physical guidance as a secondary procedure), positive reinforcement (i.e., preferred foods and toys), and sequential food presentation was implemented. The child was successful in eating many novel foods both within the clinic and home environments. A 1-year follow-up found the effects of treatment to be maintained with significant increases in number of foods eaten and significant decreases in mealtime-related behavioral challenges. The treatment implications, recommendations to clinicians, and areas of future research are discussed.

[Anesthesia and Angelman syndrome]

Angelman syndrome (AS) is a rare neurodevelopmental disorder with an incidence of 1:10,000-1:40,000 caused by deficient genetic imprinting in the chromosomal segment 15q11-q13. Experimental data suggest that the gamma-aminobutyric acid A (GABA(A)) receptor as well as the N-methyl-D-aspartate (NMDA) or α-amino-3-hydroxy-5-methyl-4-isoxazole proprionic acid (AMPA) receptors may be affected by this condition. The first description of the syndrome goes back to 1965 when the British pediatrician Harry Angelman (1915-1996) recognized similar clinical features in three children. Angelman's description of puppet children was changed to happy puppet syndrome 2 years later before this euphemistic denotation was replaced by the concept Angelman syndrome over the years. Angelman syndrome is characterized by ataxia, jerky movements especially hand flapping, a seizure disorder with a characteristic electroencephalogram (EEG), severe learning difficulties, a happy disposition, lack of verbal communication and dysmorphic facial features. Most hospitalizations are caused by epilepsy and the most common indications for surgical procedures are in dental medicine. The first anesthesiology case report to be published dates back to 2001. A total of 13 cases have now been published and in 11 cases the age was registered (mean age 11.6 years, standard deviation 11.7 and 2 outliers aged 27 and 40 years). In this paper, the published case reports are contrasted with 15 cases of anesthesia in 6 patients with AS who underwent surgery during 14 years of routine operations at a Berlin anesthesiology clinic (mean age 15.9 years, standard deviation 4.2 with no outliers). Besides neurosurgical and orthopedic operations most were dental interventions. Summarized, these cases of anesthesia and the results of the published case reports allow the formulation of guidelines for administration of anesthesia in AS cases but do not permit conclusions on which method of anesthesia is the safest for AS patients. For the preoperative consultation and anesthetization, communication with the patients requires the aid of parents or other relatives. Water and reflecting surfaces may be used to gain contact with AS patients. Patients with AS feel pain like any other person although they are frequently smiling and laughing and this has to be considered especially in major surgery (e.g. scoliosis surgery). The most important life-threatening complication is bradycardia due to vagal hypertonia which can lead to asystole with delayed response to atropine. None of the Berlin patients had severe bradycardia but the complication has to be taken into consideration. The use of drugs to ensure complete reversal of neuromuscular relaxation should be avoided because anticholinergic agents could cause bradycardia. The use of sugammadex in cases of AS has not been tested. To avoid elevation of the vagal tone, the indications for laparascopy have to be considered very carefully. There is no evidence that any drug or hypnotic may be more appropriate or advantageous. Balanced anesthesia and total intravenous anesthesia are possible but the duration of drug effect has to be taken into account. If ketamine is used the side-effects of the drug (psychomimetic reactions, muscular rigidity) should be prevented by the consistent administration of propofol, midazolam or thiopental. Usually AS patients are agitated so that regional anesthesia techniques are difficult to administer. If regional anesthesia does have considerable advantages over general anesthesia in a particular case, peripheral regional anesthesia should be preferred, especially because scoliosis is often present. There is no evidence that AS patients cause more intubation problems but because of facial dysmorphia accurate evaluation is needed in advance. This is even more important for older AS patients because the dysmorphia tends to accelerate during the course of life. Although epilepsy is the primary feature of AS, not every EEG alteration indicates the presence of epilepsy. The advantage in using neuromonitoring for measuring the depth of anesthesia is limited. Administration of anticonvulsants must be continued if they were used preoperatively.

Phenotype-environment interactions in genetic syndromes associated with severe or profound intellectual disability

The research literature notes both biological and operant theories of behavior disorder in individuals with intellectual disabilities. These two theories of genetic predisposition and operant reinforcement remain quite distinct; neither theory on its own is sufficient to explain challenging behavior in genetic syndromes and an integrated approach is required. This literature review integrates the two approaches by exploring how environmental factors can influence problem behavior in genetic syndromes associated with intellectual disability. Particular attention is paid to studies that describe evidence that problem behaviors in syndromes that are considered to be phenotypic are associated with other aspects of an established behavioral phenotype. The review highlights how the study of phenotype-environment interactions within syndromes can promote understanding of the aetiology of problem behaviors both within genetic syndromes and, ultimately, the wider population of individuals with severe intellectual disabilities. The review also evaluates the current status of research and the methods typically employed. Implications for intervention, future research and extending existing causal models of challenging behavior are discussed.

What is the evidence for environmental causes of challenging behaviors in persons with intellectual disabilities and autism spectrum disorders?

An extensive literature on the causes of challenging behaviors has been developed, primarily in the applied behavior analysis literature. One hundred and seventy-three empirical studies were reviewed where functional assessment serves as the primary method of identifying these causes. Most of the studies were able to identify a clear function or functions. Most commonly established causes were attention, the efforts to acquire tangibles, negative reinforcement in the form of escape from tasks or environments, and sensory stimulation, also described as an alone condition. Examples are provided regarding how these conditions are investigated across studies. Biological and cognitive causes have also been demonstrated. However, to date the empirical literature is limited with the bulk of studies being correlational. Considerably more research is needed, but some causes and methods to identify them are beginning to emerge.

Person characteristics of individuals in functional assessment research

This paper is a review of person characteristics that were present in 173 studies that were reviewed on functional assessment. The purpose was to give the reader an idea about the types of individuals for which functional assessment is appropriate and to outline persons and their characteristics which have the best research support. The majority of participants were diagnosed with intellectual disability and/or autism. Additionally more males that females were included and children were frequently studied versus adolescents and older adults. Finally, while the majority of studies employed experimental functional analysis, the number of participants per study was small. Conversely, functional analysis scales were used in far fewer studies, but with much larger sample sizes. Thus, relatively equal numbers of individuals have been studied with both methods.

Replacement behaviors for identified functions of challenging behaviors

Functional assessment has become a major feature of learning-based research. A critical element of the majority of these studies includes not only methods and procedures to identify the cause of the challenging behavior, but to establish replacement treatment methods. By far the most common intervention in the 176 studies we reviewed was reinforcement. Noncontingent reinforcement (NCR) was the most common reinforcement method, followed by differential reinforcement of other behavior (DRO). Reinforcement plus extinction was the second most commonly employed treatment followed by functional communication training with or without reinforcement. Researchers proved to be very creative. Forty different treatment methods were employed. The implications of these data are discussed.

The prevalence and phenomenology of self-injurious and aggressive behaviour in genetic syndromes

BACKGROUND

Self-injurious and aggressive behaviours are reported as components of some behavioural phenotypes but there are few studies comparing across syndrome groups. In this study we examined the prevalence of these behaviours and the associated person characteristics in seven genetic syndromes.

METHODS

Questionnaire data on self-injury and aggression, mood, hyperactivity, autism spectrum disorder and repetitive behaviour were collected on Angelman (AS, n=104), Cornelia de Lange (CdLS, 101), Cri du Chat (CdCS, 58), Fragile X (FXS, 191), Lowe (LS, 56), Prader-Willi (PWS, 189) and Smith-Magenis (SMS, 42) syndromes.

RESULTS

A significantly higher prevalence of self-injury was evident in CdCS, CdLS, FXS, PWS, LS and SMS. The prevalence of aggression was significantly heightened in AS and SMS. Self-injury was associated with repetitive and impulsive behaviour in CdLS, FXS, PWS and LS. Impulsivity and overactivity were significantly higher in those showing aggression across all syndrome groups.

CONCLUSIONS

These data quantify the risk for self-injury and aggression in the syndromes studied with implications for early intervention. The associations between these behaviours and person characteristics both within and between syndromes warrant further research.

Decreasing Work Refusals in an Adult With Intellectual Disability

The authors describe an intervention for work refusals in a 49-year-old man with mild mental retardation, more commonly referred to as mild intellectual disability, and other comorbid Axis I diagnoses. Following a behavioral functional assessment, Intervention A, contingent reinforcement of work attendance with cigarettes and edibles was implemented to increase work attendance. A modified reversal to baseline (Intervention B) retained the contingent reinforcement with edibles but not cigarettes. Following Intervention B, a third intervention (Intervention C) reintroduced contingent reinforcement of work attendance with cigarettes and edibles in addition to a response cost procedure. Contingent reinforcement using the most preferred reinforcer was found to be an effective intervention in increasing work attendance; however, this intervention combined with response cost was found to be superior. Overall, a 45.4% decrease in work refusals was seen from baseline following implementation of contingent reinforcement using cigarettes and edibles (Intervention A), whereas a 65.1% decrease was seen between baseline and contingent reinforcement using cigarettes and edibles combined with response cost (Intervention C). Such decrease in work refusals was maintained during follow-up. Factors responsible for intervention success and implications for clinicians are discussed.

An Examination of Psychotropic Medication Side Effects: does taking a greater number of psychotropic medications from different classes affect presentation of side effects in adults with ID?

This study examined whether the number of psychotropic medications an individual is taking across classes influences side effects among adults with Intellectual Disability (ID). Participants were 80 adults diagnosed with ID. Dependent variables were the composite score and domain scores of the Matson Evaluation of Drug Side-effects (MEDS), which is an instrument used to assess side effects. There were three levels of the independent variable: Group 1--those taking zero psychotropic medications, Group 2--those taking one psychotropic medication, and Group 3--those taking two psychotropic medications across different medication classes. There was a significant main effect regarding number of psychotropic medication classes prescribed. Further analysis revealed that four of the nine MEDS domains had significantly different mean scores for number of psychotropic medication classes. For the majority of MEDS domains, such as Central Nervous System-General, Parkinsonism/Dyskinesia, and Behavioral/Akathesia domains, participants in the no psychotropic medication group had significantly lower mean scores than those in the one and two psychotropic medication groups. Only two MEDS domains, Cardiovascular and Hematologic Effects as well as Skin, Allergies, and Temperature, were significantly different between participants taking one psychotropic medication as compared with two psychotropic medications from different classes. Implications of these findings and recommendations for future research are discussed.

Compliance Training in an Adult With Dementia of the Alzheimer’s Type and Down Syndrome

The authors describe the treatment of noncompliance and public stripping in a 53-year-old man with Down syndrome and dementia. On the basis of a review of the relevant literature and a comprehensive functional behavioral analysis, an intervention procedure utilizing contingent reinforcement of compliance is conducted. Compliance with requests to allow assistance getting dressed is reinforced with a combination of verbal praise, physical contact, and edible reinforcers. Noncompliance decreases by 85.22% at follow-up. Factors responsible for intervention success and implications for clinicians are discussed.

Compliance Training in an Adult With Dementia of the Alzheimer’s Type and Down Syndrome

The authors describe the treatment of noncompliance and public stripping in a 53-year-old man with Down syndrome and dementia. Based on a review of the relevant literature and a comprehensive functional behavioral analysis, an intervention procedure utilizing contingent reinforcement of compliance was conducted. Compliance with requests to allow assistance getting dressed was reinforced with a combination of verbal praise, physical contact, and edible reinforcers. Noncompliance had decreased by 85.22% at follow-up. Factors responsible for intervention success and implications for clinicians are discussed.