Defining the social phenotype in Williams syndrome: a model for linking gene, the brain, and behavior

Contrasting neurofunctional correlates of face- and visuospatial-processing in children and adolescents with Williams syndrome: convergent results from four fMRI paradigms

Understanding neurogenetic mechanisms underlying neuropsychiatric disorders such as schizophrenia and autism is complicated by their inherent clinical and genetic heterogeneity. Williams syndrome (WS), a rare neurodevelopmental condition in which both the genetic alteration (hemideletion of ~ twenty-six 7q11.23 genes) and the cognitive/behavioral profile are well-defined, offers an invaluable opportunity to delineate gene-brain-behavior relationships. People with WS are characterized by increased social drive, including particular interest in faces, together with hallmark difficulty in visuospatial processing. Prior work, primarily in adults with WS, has searched for neural correlates of these characteristics, with reports of altered fusiform gyrus function while viewing socioemotional stimuli such as faces, along with hypoactivation of the intraparietal sulcus during visuospatial processing. Here, we investigated neural function in children and adolescents with WS by using four separate fMRI paradigms, two that probe each of these two cognitive/behavioral domains. During the two visuospatial tasks, but not during the two face processing tasks, we found bilateral intraparietal sulcus hypoactivation in WS. In contrast, during both face processing tasks, but not during the visuospatial tasks, we found fusiform hyperactivation. These data not only demonstrate that previous findings in adults with WS are also present in childhood and adolescence, but also provide a clear example that genetic mechanisms can bias neural circuit function, thereby affecting behavioral traits.

Intensive Care Unit Analgosedation After Cardiac Surgery in Children with Williams Syndrome : a Matched Case-Control Study

OBJECTIVE

Cardiovascular abnormalities are common in patients with Williams syndrome and frequently require surgical intervention necessitating analgesia and sedation in a population with a unique neuropsychiatric profile, potentially increasing the risk of adverse cardiac events during the perioperative period. Despite this risk, the overall postoperative analgosedative requirements in patients with WS in the cardiac intensive care unit have not yet been investigated. Our primary aim was to examine the analgosedative requirement in patients with WS after cardiac surgery compared to a control group. Our secondary aim was to compare the frequency of major ACE and mortality between the two groups.

DESIGN

Matched case-control study.

SETTING

Pediatric CICU at a Tertiary Children's Hospital.

PATIENTS

Patients with WS and age-matched controls who underwent cardiac surgery and were admitted to the CICU after cardiac surgery between July 2014 and January 2021.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Postoperative outcomes and total doses of analgosedative medications were collected in the first six days after surgery for the study groups. Median age was 29.8 (12.4-70.8) months for WS and 23.5 (11.2-42.3) months for controls. Across all study intervals (48 h and first 6 postoperative days), there were no differences between groups in total doses of morphine equivalents (5.0 mg/kg vs 5.6 mg/kg, p = 0.7 and 8.2 mg/kg vs 10.0 mg/kg, p = 0.7), midazolam equivalents (1.8 mg/kg vs 1.5 mg/kg, p = 0.4 and 3.4 mg/kg vs 3.8 mg/kg, p = 0.4), or dexmedetomidine (20.5 mcg/kg vs 24.4 mcg/kg, p = 0.5 and 42.3 mcg/kg vs 39.1 mcg/kg, p = 0.3). There was no difference in frequency of major ACE or mortality.

CONCLUSIONS

Patients with WS received similar analgosedative medication doses compared with controls. There was no significant difference in the frequency of major ACE (including cardiac arrest, extracorporeal membrane oxygenation, and surgical re-intervention) or mortality between the two groups, though these findings must be interpreted with caution. Further investigation is necessary to elucidate the adequacy of pain/sedation control, factors that might affect analgosedative needs in this unique population, and the impact on clinical outcomes.

Social disinhibition in acquired brain injury and neurological disease: a concept analysis

BACKGROUND

Social disinhibition is becoming increasingly recognised in the neuropsychological literature as a complex and debilitating sequalae associated with acquired frontal lobe damage. Despite this, the term has been inconsistently defined and described in both clinical and research contexts. The purpose of this paper was to explore and examine the concept of social disinhibition in the context of brain injury and other organic neurological conditions.

METHOD

A literature search for articles published in the English language from journal inception to June 2021 was conducted using MEDLINE, PsycInfo, Embase, CINAHL and Web of Science. A 'concept analysis' was conducted on the identified literature using Walker & Avant's (2019) framework.

RESULTS

The analysis suggested that while several terms are often used interchangeably with social disinhibition, including impulsivity and behavioural dysregulation, these terms may be differentiated and defined separately within the broader domain of 'behaviours of concern'. Attributes, antecedents and consequences of social disinhibition were also identified and discussed.

CONCLUSIONS

Clarifying the concept of social disinhibition has important implications in both clinical and research contexts, including increased understanding of the behaviours, more accurate estimates of incidence and prevalence, and the development and implementation of targeted rehabilitation programmes.

The social phenotype associated with Wiedemann-Steiner syndrome: Autistic traits juxtaposed with high social drive and prosociality

The aim of this study was to provide a descriptive overview of the social characteristics associated with Wiedemann-Steiner syndrome (WSS). A total of 24 parents of children/adults with WSS (11F, mean age = 12.94 years, SD = 8.00) completed the Social Responsiveness Scale 2nd Edition (SRS-2); Colorado Learning Difficulties Questionnaire (CLDQ) and Strengths and Difficulties Questionnaire (SDQ). Almost half our sample reported a diagnosis of autism spectrum disorder (ASD) and 70% had intellectual disability. On the SDQ, over 90% of participants were rated in borderline/clinical ranges in Peer Problems, yet the majority fell within normal limits in Prosocial Behaviors. Most fell in the moderate/severe difficulties ranges across SRS-2 Social Cognition, Communication, and Restricted/Repetitive Behaviors scales (all >70%); whereas substantially less participants met these ranges for deficits in Social Awareness (50%) and Social Motivation (33.33%). A pattern of relatively strong prosocial skills and social drive in the context of difficulties with inflexible behaviors, social cognition, and communication was observed, regardless of gender, ASD or intellectual disability diagnosis. The social phenotype associated with WSS is characterized by some autistic features paired with unusually high social motivation and prosocial tendencies.

Autism spectrum disorder symptom expression in individuals with 3q29 deletion syndrome

BACKGROUND

The 1.6 Mb 3q29 deletion is associated with neurodevelopmental and neuropsychiatric phenotypes, including a 19-fold increased risk for autism spectrum disorder (ASD). Previous work by our team identified elevated social disability in this population via parent-report questionnaires. However, clinical features of ASD in this population have not been explored in detail.

METHODS

Thirty-one individuals with 3q29 deletion syndrome (3q29del, 61.3% male) were evaluated using two gold-standard clinical ASD evaluations: the Autism Diagnostic Observation Schedule, Second Edition (ADOS-2), and the Autism Diagnostic Interview, Revised (ADI-R). Four matched comparators for each subject were ascertained from the National Database for Autism Research. Item-level scores on the ADOS-2 and ADI-R were compared between subjects with 3q29del and matched comparators.

RESULTS

Subjects with 3q29del and no ASD (3q29del-ASD) had greater evidence of social disability compared to typically developing (TD) comparison subjects across the ADOS-2. Subjects with 3q29del and ASD (3q29del + ASD) were largely indistinguishable from non-syndromic ASD (nsASD) subjects on the ADOS-2. 3q29del + ASD performed significantly better on social communication on the ADI-R than nsASD (3q29 + ASD mean = 11.36; nsASD mean = 15.70; p = 0.01), and this was driven by reduced deficits in nonverbal communication (3q29 + ASD mean = 1.73; nsASD mean = 3.63; p = 0.03). 3q29del + ASD reported significantly later age at the first two-word phrase compared to nsASD (3q29del + ASD mean = 43.89 months; nsASD mean = 37.86 months; p = 0.01). However, speech delay was not related to improved nonverbal communication in 3q29del + ASD.

LIMITATIONS

There were not enough TD comparators with ADI-R data in NDAR to include in the present analysis. Additionally, our relatively small sample size made it difficult to assess race and ethnicity effects.

CONCLUSIONS

3q29del is associated with significant social disability, irrespective of ASD diagnosis. 3q29del + ASD have similar levels of social disability to nsASD, while 3q29del-ASD have significantly increased social disability compared to TD individuals. However, social communication is reasonably well preserved in 3q29del + ASD relative to nsASD. It is critical that verbal ability and social disability be examined separately in this population to ensure equal access to ASD and social skills evaluations and services.

Differences and Similarities in Adaptive Functioning between Children with Autism Spectrum Disorder and Williams-Beuren Syndrome: A Longitudinal Study

Background: The last decade has seen a growing number of comparative studies on adaptive profiles between individuals with autism spectrum disorder (ASD) and Williams–Beuren syndrome (WBS), showing shared and syndrome-specific adaptive trajectories. Studies have revealed similarities in global adaptive profiles across conditions, while some differences have been found in preschoolers on the specific sub-domains of communication and socialization. However, the majority of studies that have focused on the differences in adaptive functioning across these two conditions used a cross-sectional design. To the best of our knowledge, there are no studies exploring the differences and similarities of adaptive functioning over time. Methods: We compared longitudinal data of adaptive functioning measured by Vineland Adaptive Behavior Scales (VABS) between two samples of children and adolescents with ASD and WBS, matched for chronological age and cognitive/developmental level at the time of the first evaluation. Results and Conclusions: We did not find any difference on the global adaptive level, both at the first evaluation and over time. However, significant differences emerged on the socialization and communication levels at the time of recruitment. Longitudinal data show that only the socialization domain remains different over time, with individuals with WBS having better functioning than those with ASD. The results on shared and distinct patterns of adaptive functioning between disorders are discussed from a developmental perspective, thus contributing to the implementation of age-specific interventions.

Psychotic Symptoms and Malignant Neuroleptic Syndrome in Williams Syndrome: A Case Report

BACKGROUND

Somatic and mental comorbidities are characteristic of individuals with Williams syndrome. The psychiatric profile of these patients mainly comprises affective disorders, while psychotic symptoms are rare.

METHODS

We present a case report of psychosis and malignant neuroleptic syndrome in a patient with Williams syndrome. We also conduct a review of recent works on the topic.

CASE PRESENTATION

A 38-year-old Caucasian male with Williams syndrome presented with somatic delusions, previously experiencing severe anxiety and concerns about a headache. The patient was prescribed olanzapine, which did not, however, have any effect on the delusions. After switching to lurasidone, the patient presented with malignant neuroleptic syndrome (muscle rigidity, tremor, urinary retention, fluctuating level of consciousness). He was hospitalized and the antipsychotic medication was discontinued. After somatic recovery, the patient did not experience severe anxiety and the somatic delusions diminished notably. The patient was discharged from the hospital in a stable physical condition, albeit still with transient worries about his health condition.

CONCLUSIONS

We present a case of the coincidence of Williams syndrome and psychosis. We hypothesize on the possible pathological relationships between the onset of the psychosis and severe anxiety in an individual with Williams syndrome. This case report duly contributes to the limited literature on psychiatric comorbidity in Williams syndrome.

Oxytocin and Oxytocin Receptor Gene Regulation in Williams Syndrome: A Systematic Review

Williams Syndrome (WS) is a rare genetic multisystem disorder that occurs because of a deletion of approximately 25 genes in the 7q11.23 chromosome region. This causes dysmorphic facial appearances, multiple congenital cardiovascular defects, delayed motor skills, and abnormalities in connective tissues and the endocrine system. The patients are mostly diagnosed with mild to moderate mental retardation, however, they have a hyper sociable, socially dis-inhibited, and outgoing personality, empathetic behavior, and are highly talkative. Oxytocin (OT), a neuropeptide synthesized at the hypothalamus, plays an important role in cognition and behavior, and is thought to be affecting WS patients' attitudes at its different amounts. Oxytocin receptor gene (OXTR), on chromosome 3p25.3, is considered regulating oxytocin receptors, via which OT exerts its effect. WS is a crucial disorder to understand gene, hormone, brain, and behavior associations in terms of sociality and neuropsychiatric conditions. Alterations to the WS gene region offer an opportunity to deepen our understandings of autism spectrum disorder, schizophrenia, anxiety, or depression. We aim to systematically present the data available of OT/OXTR regulation and expression, and the evidence for whether these mechanisms are dysregulated in WS. These results are important, as they predict strong epigenetic control over social behavior by methylation, single nucleotide polymorphisms, and other alterations. The comparison and collaboration of these studies may help to establish a better treatment or management approach for patients with WS if backed up with future research.

Cooperative Parent-Mediated Therapy in Children with Fragile X Syndrome and Williams Beuren Syndrome: A Pilot RCT Study of a Transdiagnostic Intervention-Preliminary Data

Children with fragile X syndrome and William Beuren syndrome share several socio-communicative deficits. In both populations, around 30/35% of individuals meets criteria for autism spectrum disorder on gold standard instruments. Notwithstanding, few studies have explored feasibility and validity of therapy for socio-communicative deficits in individuals with these genetic conditions. In this study, we present preliminary data on a pilot RCT aimed to verify the effectiveness of cooperative parent-mediated therapy for socio-communicative deficits in a transdiagnostic perspective in a small sample of 12 participants. Our preliminary data showed that the experimental group had significant improvement in one socio-communicative skill (responsivity) and in clinical global impression, while the control group in an adaptive measure of socialization and word production. Implications of these results are then discussed.

The effects of psychopathology and shame on social representations of health and lifestyle behaviours via free association: a graph analysis approach

BACKGROUND

There is a knowledge gap in whether psychopathology aspects can shape and mark the social representations about health and lifestyle. In this work, we investigated the association of psychopathology and shame with the centrality of the words describing eight common social representations of health and lifestyle.

METHODS

A convenience sample of 288 adults participated with an average age of 44.7, and 62.6% were women. The participants were asked to express three consecutive words associated with eight different health and lifestyle experiences by utilizing the free association method. The participants also were completed the Symptom Checklist-90-Revised (SCL-90-R), the Experiences of Shame Scale (ESS), and the Other as Shamer Scale (OAS). Canonical correlation analysis was applied to investigate the relationship between the set of the eight-word centralities and the psycho-demographic variables consisting of the subject's age and gender, the SCL 90 subscales, the OAS, and the ESS. Based on these findings, a structural equation explorative model was formed to test the unidimensionality of the five centralities construct.

RESULTS

Τhe psychological characteristics of interpersonal sensitivity, depression, external shame, and hostility were found to affect the word selection process on the social representations concerning nightlife, health, diet, lifestyle, and alcohol consumption. Participants with increased levels of depression tend to choose more centrally positioned words when the stimulus word was diet and more decentralized responses when the stimulus word was health. At the same time, higher external shame corresponded to more decentralized words for the categories of health and lifestyle.

CONCLUSIONS

Our results indicate that there is a potential interaction between the psychological state and how a social representation of health and lifestyle is constructed through selected words. Graph theory emerged as an additional tool to use to study these relations.

Parents' perspective on the social traits observed in school-age children with autism and children with Williams syndrome

Individuals with autism spectrum disorders and those with Williams syndrome often have impairments in social behaviors. These two neurodevelopmental disorders are often reputed to be on the opposite ends of the social spectrum, with autistic individuals being socially avoidant and those with Williams syndrome highly social. Most research on children with autism and Williams syndrome has focused on preschool and younger school-age children. The current study assessed school-age children between the ages of 7-14 years with high-functioning autism, Williams syndrome, and neurotypical developing peers. Parents completed the Salk Institute Sociability Questionnaire and the Social Responsiveness Scale, to provide unique insights into social functioning and tap into different behavioral areas, social approach behaviors, and social responsiveness. This study provides additional evidence that young children with autism and Williams syndrome continue to show divergent social-behavioral tendencies at school-age, despite controlling for age and intellect. Results of this study better elucidate disparities as well as commonalities across school-age children with neurodevelopmental disorders and their typically developing peers, providing insight into everyday social functioning.

Sharing Experiences in Infancy: From Primary Intersubjectivity to Shared Intentionality

We contrast two theses that make different assumptions about the developmental onset of human-unique sociality. The primary intersubjectivity thesis (PIT) argues that humans relate to each other in distinct ways from the beginning of life, as is shown by newborns' participation in face-to-face encounters or "primary intersubjectivity." According to this thesis, humans' innate relational capacity is the seedbed from which all subsequent social-emotional and social-cognitive developments continuously emerge. The shared intentionality thesis (SIT) states that human-unique forms of interaction develop at 9-12 months of age, when infants put their heads together with others in acts of object-focused joint attention and simple collaborative activities. According to this thesis, human-unique cognition emerges rapidly with the advent of mind-reading capacities that evolved specifically for the purpose of coordination. In this paper, we first contrast the two theses and then sketch the outlines of an account that unifies their strengths. This unified account endorses the PIT's recognition of the fundamental importance of primary intersubjectivity. Any act of sharing experiences is founded on the communicative capacity that is already displayed by young infants in primary intersubjectivity. At the same time, we question the PIT's interpretation that dyadic encounters have the triadic structure of joint attention. Lastly, we draw on empirical work on the development of joint attention, imitation, and social referencing that serves as evidence that primary intersubjectivity continuously unfolds into the capacity for triadic joint attention.

Abnormal auditory event-related potentials in Williams syndrome

Individuals with Williams Syndrome (WS) have specific auditory characteristics, including hypoacusis and hyperacusis, and music appreciation skills. Little is known about the functionality of the central auditory nervous system (CANS) for sound processing in WS. Thus, the objective of the present study was to evaluate the functionality of the CANS in individuals with WS, based on auditory event-related potentials, as far as cognitive and behavioral aspects are concerned. The study was carried out with 17 individuals, seven females and ten males, between seven and 17 years old, with WS, and 17 individuals with typical development matched by sex and chronological age to individuals with WS. None of these individuals had middle ear impairment or hearing loss. The subjects were evaluated for intelligence quotient, loudness discomfort level, and auditory event-related potentials with Tone Burst stimuli, on the oddball paradigm; the parents also answered the MTA-SNAP-IV questionnaire. Hyperacusis was found in six WS individuals and two individuals with typical development. In the present study, WS individuals present longer latency and reduced amplitude for P1, N1, N2 and P3 components. These results, suggesting a delay and hypoactive responses of the CANS in this syndrome, that cannot be related to the cognitive or behavioral aspects of these individuals, but it indicates a cortical immaturity to process acoustic stimuli.

Comparison of Adaptive Functioning in Children with Williams Beuren Syndrome and Autism Spectrum Disorder: A Cross-Syndrome Study

Williams Beuren syndrome (WBS) and autism spectrum disorder (ASD) have been long considered as "polar opposite" disorders. Although children with WBS appears to be hypersociable, recent researches have revealed difficulties in socio-communicative skills such as shared attention, showing or giving objects, social relationships comprehension, pragmatic use of language, and emotion's recognition. The aim of this cross-syndrome study is to compare clinician-report adaptive profiles of two wide developmental range children by means of Vineland Adaptive Behavior Scales-Interview Edition, Survey Form. Eighty individuals, 40 with WBS and 40 with ASD (31 preschoolers and 49 scholars) with ASD and WBS matched for chronological age and developmental/cognitive level were recruited. Analysis of domains and subdomains have been reported. Results showed no significant difference in global adaptive level between WBS and ASD in both preschooler and scholar children. Communication domain significantly differ in preschoolers (higher in WBS children), but not in scholars. Expressive subdomain significantly differ in both preschoolers and scholars (higher in WBS children). Play and Leisure subdomain significantly differ in scholars (higher in WBS children), but not in preschoolers. Our results support hypothesis on a shared global adaptive impairment in children with WBS and ASD, by extending this findings to scholar-age children. Analysis of domains and subdomains differences highlight the need for interventions targeting social-pragmatic skills since first years of life. Differences in preschoolers and scholars adaptive profiles could be explained through a developmental perspective. LAY SUMMARY: Little is known about differences in adaptive profiles between Williams Beuren syndrome and autism spectrum disorder. Our results show similarities in global adaptive level and difference in communication level. Furthermore, expressive skills seem to be higher in Williams Beuren Syndrome. Autism Res 2021, 14: 748-758. © 2020 International Society for Autism Research and Wiley Periodicals LLC.

Expressivity in children with autism and Williams syndrome

Purpose

The purpose of this study is to investigate the social and affective aspects of communication in school-age children with HFA and school-age children with WS using a micro-analytic approach. Social communication is important for success at home, school, work and in the community. Lacking the ability to effectively process and convey information can lead to deficits in social communication. Individuals with high functioning autism (HFA) and individuals with Williams syndrome (WS) often have significant impairments in social communication that impact their relationships with others. Currently, little is known about how school-age children use and integrate verbal and non-verbal behaviors in the context of a social interaction.

Design/methodology/approach

A micro-analytic coding scheme was devised to reveal which channels children use to convey information. Language, eye gaze behaviors and facial expressions of the child were coded during this dyadic social interaction. These behaviors were coded throughout the entire interview, as well as when the child was the speaker and when the child was the listener.

Findings

Language results continue to pose problems for the HFA and WS groups compared to their typically developing (TD) peers. For non-verbal communicative behaviors, a qualitative difference in the use of eye gaze was found between the HFA and WS groups. For facial expression, the WS and TD groups produced more facial expressions than the HFA group.

Research limitations/implications

No differences were observed in the HFA group when playing different roles in a conversation, suggesting they are not as sensitive to the social rules of a conversation as their peers. Insights from this study add knowledge toward understanding social-communicative development in school-age children.

Originality/value

In this study, two non-verbal behaviors will be assessed in multiple contexts: the entire biographical interview, when the child is the speaker and when the child is the listener. These social and expressive measures give an indication of how expressive school-age children are and provide information on their attention, affective state and communication skills when conversing with an adult. Insights from this study will add knowledge toward understanding social-communicative development in school-age children.

An Exploration of Social Cognition in Children with Different Degrees of Genetic Deletion in Williams Syndrome

An explanation for the social dysfunction observed in Williams syndrome may be deficits in social cognition. This study explored aspects of social cognition in children with Williams syndrome with different genotypes. The 12 participants included one with a 1.1 Mb deletion that retained the GTF2IRD1, GTF2I, and GTF2IRD2 genes, seven with a 1.5 Mb deletion that preserved the GTF2IRD2 gene, and four with a 1.8 Mb deletion with loss of all three genes. The participant retaining all three genes was found to have better performance on social judgment and first-order theory of mind tasks than the group with loss of all three genes. These results may reflect the influence of the GTF2I gene family on social cognition in Williams syndrome.

Hearing the feeling: Auditory emotion perception in Williams syndrome

BACKGROUND

Studies investigating recognition of facial expressions of emotions in Williams syndrome (WS) have reported difficulties in recognising negative expressions of emotion and a reliance on atypically developing underlying processes during task performance.

AIM

The aim of the study was to extend these findings to the recognition of emotions in auditory domains.

METHOD AND PROCEDURES

Children and adolescents with WS, together with chronological (CA) and verbal mental age matched (VMA) typically developing (TD) comparison groups, were asked to judge expressions of happiness, sadness, anger, and fear in vocal and musical conditions.

OUTCOMES AND RESULTS

Total emotion recognition scores did not differ between WS and VMA matched groups but profiles of discrimination across emotion categories were markedly different. For all groups, the accessibility of emotion category cues differed across music and speech domains. The results suggested that emotion discrimination is more strongly linked with cognitive ability in WS than in TD.

CONCLUSIONS AND IMPLICATIONS

Although WS and TD groups showed a significantly different profile of discrimination across emotion categories, similarities in the pattern of discrimination across domains and in the correlates of auditory emotion processing were observed. The results are discussed in the context of typical and atypical developmental trajectories and compensatory mechanisms in WS.

Decreased density of cholinergic interneurons in striatal territories in Williams syndrome

Williams syndrome (WS) is a rare neurodevelopmental disorder caused by the hemideletion of approximately 25-28 genes at 7q11.23. Its unusual social and cognitive phenotype is most strikingly characterized by the disinhibition of social behavior, in addition to reduced global IQ, with a relative sparing of language ability. Hypersociality and increased social approach behavior in WS may represent a unique inability to inhibit responses to specific social stimuli, which is likely associated with abnormalities of frontostriatal circuitry. The striatum is characterized by a diversity of interneuron subtypes, including inhibitory parvalbumin-positive interneurons (PV+) and excitatory cholinergic interneurons (Ch+). Animal model research has identified an important role for these specialized cells in regulating social approach behavior. Previous research in humans identified a depletion of interneuron subtypes associated with neuropsychiatric disorders. Here, we examined the density of PV+ and Ch+ interneurons in the striatum of 13 WS and neurotypical (NT) subjects. We found a significant reduction in the density of Ch+ interneurons in the medial caudate nucleus and nucleus accumbens, important regions receiving cortical afferents from the orbitofrontal and ventromedial prefrontal cortex, and circuitry involved in language and reward systems. No significant difference in the distribution of PV+ interneurons was found. The pattern of decreased Ch+ interneuron densities in WS differs from patterns of interneuron depletion found in other disorders.

Siblings of children with Williams syndrome: Correlates of psychosocial adjustment and sibling relationship quality

BACKGROUND

Previous research has examined adjustment in parents of children with Williams syndrome (WS), but little is known about sibling outcomes.

AIMS

To explore sibling adjustment and relationship quality, and their demographic, psychological and behavioural phenotypic correlates from the perspective of caregivers and siblings in families of children with WS.

METHODS AND PROCEDURES

Forty-one caregivers of children with WS participated in this questionnaire study on the adjustment and relationship quality of the siblings. In 31 of these families, self-report data were also provided by the siblings themselves. Data were also gathered on potential correlates, including anxiety and social functioning in the child with WS, caregiver mental health, and sibling social support.

OUTCOMES AND RESULTS

Sibling adjustment was similar to population norms, though significantly increased caregiver-reported emotional difficulties were found. Siblings reported greater behavioural, emotional and relationship difficulties than caregivers perceived them to have. Some significant associations were found between the behaviour of the child with WS, sibling behaviour problems and sibling relationship quality.

CONCLUSIONS AND IMPLICATIONS

A picture of relatively positive sibling adjustment and relationships emerged, but findings of individual differences and some emotional difficulties emphasise the need for an individualised approach to support in families of children with WS.

Anxiety in Williams Syndrome: The Role of Social Behaviour, Executive Functions and Change Over Time

Anxiety is a prevalent mental health issue for individuals with Williams syndrome (WS). Relatively little is known about the developmental course of anxiety, or how it links with core features of WS, namely social and executive functioning (EF). In this study, parent-reports of anxiety were compared across a 4-year period (N = 17), and links between anxiety, social and EF were explored from concurrent parent-reports (N = 26). Results indicated that high anxiety persisted over time, and anxiety was related to impairments in both social and executive functioning. Importantly, results indicated that impairments in EFs may drive the links between anxiety and social functioning. This timely investigation provides new insights into anxiety in WS and highlights potential areas for intervention.

Williams Syndrome, Human Self-Domestication, and Language Evolution

Language evolution resulted from changes in our biology, behavior, and culture. One source of these changes might be human self-domestication. Williams syndrome (WS) is a clinical condition with a clearly defined genetic basis which results in a distinctive behavioral and cognitive profile, including enhanced sociability. In this paper we show evidence that the WS phenotype can be satisfactorily construed as a hyper-domesticated human phenotype, plausibly resulting from the effect of the WS hemideletion on selected candidates for domestication and neural crest (NC) function. Specifically, we show that genes involved in animal domestication and NC development and function are significantly dysregulated in the blood of subjects with WS. We also discuss the consequences of this link between domestication and WS for our current understanding of language evolution.

Características da avaliação auditiva na síndrome de Williams: revisão sistemática

RESUMO Objetivo Identificar por meio de uma revisão sistemática da literatura quais são as características da avaliação audiológica clínica de indivíduos com síndrome de Williams. Estratégia de pesquisa Inicialmente foi determinada a seguinte pergunta de pesquisa: “Quais são as características da avaliação auditiva clínica em indivíduos com síndrome de Williams?”. A partir desta, foi realizado um levantamento bibliográfico em 4 bases de dados, utilizando-se dos seguintes descritores: síndrome de Williams (Williams syndrome), perda auditiva (hearing loss) e audiologia (audiology). Critérios de seleção Foram selecionados artigos com nível de evidência 1 ou 2, publicados na íntegra nos idiomas português brasileiro ou inglês. Análise dos dados Foram analisados os resultados obtidos nos testes auditivos utilizados na rotina clínica, incluindo: imitanciometria, audiometria tonal, emissões otoacústicas e potencial evocado auditivo de tronco encefálico. Resultados 209 estudos foram encontrados, porém apenas 12 contemplaram os critérios de inclusão para o estudo. Foi possível observar prevalência de curva timpanométrica do tipo A, que pode ocorrer juntamente com ausência de reflexos acústicos, perda auditiva neurossensorial de grau leve a moderado acometendo principalmente as frequências altas, emissões otoacústicas ausentes ou de menor amplitude e potencial evocado auditivo de tronco encefálico sem alteração retrococlear. Conclusão O comprometimento coclear é comum em indivíduos com síndrome de Williams e as principais alterações na avaliação auditiva nesta população são a ausência das emissões otoacústicas e dos reflexos acústicos bem como a presença de perda auditiva neurossensorial de grau leve a moderado principalmente nas frequências altas na audiometria tonal.

Reading Deficits in Intellectual Disability Are still an Open Question: A Narrative Review

BACKGROUND

In children with intellectual disability (ID), the acquisition of reading skills constitutes a basic step towards the possibility of independent living, social inclusion and participation.

METHODS

We carried out a narrative review of the literature on reading fluency and accuracy of individuals with ID resulting from different genetic syndromes (Fragile X, Williams, Velocardiofacial, Prader-Willi, and Down syndrome). Our aim was to define their reading profiles in light of the dual-route reading model. For this purpose, studies that examined both word and non-word reading in children with ID were included in the analysis.

RESULTS

Seventeen studies emerged based on the selection criteria. The results were different depending on the control group used. A deficit in reading non-words emerged in studies that used the reading-level match design but not when standardized scores were used, when controls were age-matched or when a mental age matching was used. Thus, a deficit in reading non-words emerged only in studies that used the reading-level match design. However, severe methodological criticisms were recently raised about the use of this matching design.

CONCLUSIONS

In view of the methodological problems in using grade equivalents, it is premature to draw definite conclusions about the reading profile of children with ID resulting from different genetic syndromes. In any case, the reviewed evidence provides little support for the idea that children with ID have selective difficulty in phonological reading. Thus, the reading profile of children with ID remains an open question that needs to be investigated by means of methodologically sound research.

Cognitive and behavioral profile of Williams Syndrome toddlers

PURPOSE

To verify indicators of cognitive development, receptive language skills and adaptive behavioral patterns in toddlers with Williams syndrome (WS).

METHODS

The sample comprised 8 children of both sex, aged between 48 and 72 months with WS. Instruments of data collection were Denver Developmental Screening Test II; Peabody Picture Vocabulary Test; Vineland Adaptive Behavior Scale; Child Behavior Checklist for Ages 1½-5and 6 to 18; Columbia Mental Maturity Scale (CMMS), and Behavior Problems Inventory-01.

RESULTS

The major developmental impairments were associated with fine motor skills and personal care abilities. Deficits in receptive language and communication skills were reported according to the PPVT and Denver II, respectively. The caregivers reported behavioral and emotional problems associated to anxiety and depression, and attention problems scales of CBCL.

CONCLUSION

The toddlers demonstrated deficits in adaptive functioning and behavioral, motor and cognitive difficulties such as inattention and hyperactivity, stereotypies and aggressive behavior.

Explicit Oral Narrative Intervention for Students with Williams Syndrome

Narrative skills play a crucial role in organizing experience, facilitating social interaction and building academic discourse and literacy. They are at the interface of cognitive, social, and linguistic abilities related to school engagement. Despite their relative strengths in social and grammatical skills, students with Williams syndrome (WS) do not show parallel cognitive and pragmatic performance in narrative generation tasks. The aim of the present study was to assess retelling of a TV cartoon tale and the effect of an individualized explicit instruction of the narrative structure. Participants included eight students with WS who attended different special education levels. Narratives were elicited in two sessions (pre and post intervention), and were transcribed, coded and analyzed using the tools of the CHILDES Project. Narratives were coded for productivity and complexity at the microstructure and macrostructure levels. Microstructure productivity (i.e., length of narratives) included number of utterances, clauses, and tokens. Microstructure complexity included mean length of utterances, lexical diversity and use of discourse markers as cohesive devices. Narrative macrostructure was assessed for textual coherence through the Pragmatic Evaluation Protocol for Speech Corpora (PREP-CORP). Macrostructure productivity and complexity included, respectively, the recall and sequential order of scenarios, episodes, events and characters. A total of four intervention sessions, lasting approximately 20 min, were delivered individually once a week. This brief intervention addressed explicit instruction about the narrative structure and the use of specific discourse markers to improve cohesion of story retellings. Intervention strategies included verbal scaffolding and modeling, conversational context for retelling the story and visual support with pictures printed from the cartoon. Results showed significant changes in WS students' retelling of the story, both at macro- and microstructure levels, when assessed following a 2-week interval. Outcomes were better in microstructure than in macrostructure, where sequential order (i.e., complexity) did not show significant improvement. These findings are consistent with previous research supporting the use of explicit oral narrative intervention with participants who are at risk of school failure due to communication impairments. Discussion focuses on how assessment and explicit instruction of narrative skills might contribute to effective intervention programs enhancing school engagement in WS students.

Consistent hypersocial behavior in mice carrying a deletion of Gtf2i but no evidence of hyposocial behavior with Gtf2i duplication: Implications for Williams-Beuren syndrome and autism spectrum disorder

Introduction

Williams-Beuren syndrome (WBS) is a developmental disorder caused by hemizygous deletion of human chromosome 7q11.23. Hypersocial behavior is one symptom of WBS and contrasts with hyposociality observed in autism spectrum disorder (ASD). Interestingly, duplications of 7q11.23 have been associated with ASD. The social phenotype of WBS has been linked to GTF2I or general transcription factor IIi (TFII-I). Duplication of GTF2I has also been associated with ASD.

Methods

We compared mice having either a deletion (Gtf2i+/- ) or duplication (Gtf2i+/dup ) of Gtf2i to wild-type (Gtf2i+/+ ) littermate controls in a series of behavioral tasks including open-field activity monitoring, olfactory probes, a social choice task, social transmission of food preference, habituation-dishabituation, and operant social motivation paradigms.

Results

In open-field observations, Gtf2i+/- and Gtf2i+/dup mice demonstrated normal activity and thigmotaxis, and surprisingly, each strain showed a significant preference for a stimulus mouse that was not observed in Gtf2i+/+ siblings. Both Gtf2i+/- and Gtf2i+/dup mice demonstrated normal olfaction in buried food probes, but the Gtf2i+/- mice spent significantly more time investigating urine scent versus water, which was not observed in the other strains. Gtf2i+/- mice also spent significantly more time in nose-to-nose contact compared to Gtf2i+/+ siblings during the open-field encounter of the social transmission of food preference task. In operant tasks of social motivation, Gtf2i+/- mice made significantly more presses for social rewards than Gtf2i+/+ siblings, while there was no difference in presses for the Gtf2i+/dup mice.

Discussion

Results were remarkably consistent across testing paradigms supporting a role for GTF2i in the hypersocial phenotype of WBS and more broadly in the regulation of social behavior. Support was not observed for the role of GTF2i in ASD.

The Williams syndrome prosociality gene GTF2I mediates oxytocin reactivity and social anxiety in a healthy population

The neurohormone oxytocin plays a central role in human social behaviour and cognition, and oxytocin dysregulation may contribute to psychiatric disorders. However, genetic factors influencing individual variation in the oxytocinergic system remain poorly understood. We genotyped 169 healthy adults for a functional polymorphism in GTF2I (general transcription factor II-I), a gene associated with high prosociality and reduced social anxiety in Williams syndrome, a condition reported to involve high oxytocin levels and reactivity. Participants' salivary oxytocin levels were measured before and after watching a validated empathy-inducing video. Oxytocin reactivity, defined as pre- to post-video percentage change in salivary oxytocin, varied substantially and significantly between individuals with different GTF2I genotypes, with, additionally, a trend towards an interaction between genotype and sex. Individuals with more oxytocin-reactive genotypes also reported significantly lower social anxiety. These findings suggest a model whereby GTF2I has a continuum of effects on human sociality, from the extreme social phenotypes and oxytocin dysregulation associated with gene deletion in Williams syndrome, to individual differences in oxytocin reactivity and sociality associated with common polymorphisms in healthy populations.

Increased glia density in the caudate nucleus in williams syndrome: Implications for frontostriatal dysfunction in autism

Williams syndrome (WS) is a rare neurodevelopmental disorder with a well-described, known genetic etiology. In contrast to Autism Spectrum Disorders (ASD), WS has a unique phenotype characterized by global reductions in IQ and visuospatial ability, with relatively preserved language function, enhanced reactivity to social stimuli and music, and an unusual eagerness to interact socially with strangers. A duplication of the deleted region in WS has been implicated in a subset of ASD cases, defining a spectrum of genetic and behavioral variation at this locus defined by these opposite extremes in social behavior. The hypersociability characteristic of WS may be linked to abnormalities of frontostriatal circuitry that manifest as deficits in inhibitory control of behavior. Here, we examined the density of neurons and glia in associative and limbic territories of the striatum including the caudate, putamen, and nucleus accumbens regions in Nissl stained sections in five pairs of age, sex, and hemisphere-matched WS and typically-developing control (TD) subjects. In contrast to what is reported in ASD, no significant increase in overall neuron density was observed in this study. However, we found a significant increase in the density of glia in the dorsal caudate nucleus, and in the ratio of glia to neurons in the dorsal and medial caudate nucleus in WS, accompanied by a significant increase in density of oligodendrocytes in the medial caudate nucleus. These cellular abnormalities may underlie reduced frontostriatal activity observed in WS, with implications for understanding altered connectivity and function in ASD. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 78: 531-545, 2018.

Increased overall cortical connectivity with syndrome specific local decreases suggested by atypical sleep-EEG synchronization in Williams syndrome

Williams syndrome (7q11.23 microdeletion) is characterized by specific alterations in neurocognitive architecture and functioning, as well as disordered sleep. Here we analyze the region, sleep state and frequency-specific EEG synchronization of whole night sleep recordings of 21 Williams syndrome and 21 typically developing age- and gender-matched subjects by calculating weighted phase lag indexes. We found broadband increases in inter- and intrahemispheric neural connectivity for both NREM and REM sleep EEG of Williams syndrome subjects. These effects consisted of increased theta, high sigma, and beta/low gamma synchronization, whereas alpha synchronization was characterized by a peculiar Williams syndrome-specific decrease during NREM states (intra- and interhemispheric centro-temporal) and REM phases of sleep (occipital intra-area synchronization). We also found a decrease in short range, occipital connectivity of NREM sleep EEG theta activity. The striking increased overall synchronization of sleep EEG in Williams syndrome subjects is consistent with the recently reported increase in synaptic and dendritic density in stem-cell based Williams syndrome models, whereas decreased alpha and occipital connectivity might reflect and underpin the altered microarchitecture of primary visual cortex and disordered visuospatial functioning of Williams syndrome subjects.

A Common Polymorphism in a Williams Syndrome Gene Predicts Amygdala Reactivity and Extraversion in Healthy Adults

BACKGROUND

Williams syndrome (WS), a genetic disorder resulting from hemizygous microdeletion of chromosome 7q11.23, has emerged as a model for identifying the genetic architecture of socioemotional behavior. Common polymorphisms in GTF2I, which is found within the WS microdeletion, have been associated with reduced social anxiety in the general population. Identifying neural phenotypes affected by these polymorphisms would help advance our understanding not only of this specific genetic association but also of the broader neurogenetic mechanisms of variability in socioemotional behavior.

METHODS

Through an ongoing parent protocol, the Duke Neurogenetics Study, we measured threat-related amygdala reactivity to fearful and angry facial expressions using functional magnetic resonance imaging, assessed trait personality using the Revised NEO Personality Inventory, and imputed GTF2I rs13227433 from saliva-derived DNA using custom Illumina arrays. Participants included 808 non-Hispanic Caucasian, African American, and Asian university students.

RESULTS

The GTF2I rs13227433 AA genotype, previously associated with lower social anxiety, predicted decreased threat-related amygdala reactivity. An indirect effect of GTF2I genotype on the warmth facet of extraversion was mediated by decreased threat-related amygdala reactivity in women but not men.

CONCLUSIONS

A common polymorphism in the WS gene GTF2I associated with reduced social anxiety predicts decreased threat-related amygdala reactivity, which mediates an association between genotype and increased warmth in women. These results are consistent with reduced threat-related amygdala reactivity in WS and suggest that common variation in GTF2I contributes to broader variability in socioemotional brain function and behavior, with implications for understanding the neurogenetic bases of WS as well as social anxiety.

Anxiety and autonomic response to social-affective stimuli in individuals with Williams syndrome

BACKGROUND

Williams syndrome (WS) is a genetic condition characterized by an unusual "hypersocial" personality juxtaposed by high anxiety. Recent evidence suggests that autonomic reactivity to affective face stimuli is disorganised in WS, which may contribute to emotion dysregulation and/or social disinhibition.

METHODS

Electrodermal activity (EDA) and mean interbeat interval (IBI) of 25 participants with WS (19 - 57 years old) and 16 typically developing (TD; 17-43 years old) adults were measured during a passive presentation of affective face and voice stimuli. The Beck Anxiety Inventory was administered to examine associations between autonomic reactivity to social-affective stimuli and anxiety symptomatology.

RESULTS

The WS group was characterized by higher overall anxiety symptomatology, and poorer anger recognition in social visual and aural stimuli relative to the TD group. No between-group differences emerged in autonomic response patterns. Notably, for participants with WS, increased anxiety was uniquely associated with diminished arousal to angry faces and voices. In contrast, for the TD group, no associations emerged between anxiety and physiological responsivity to social-emotional stimuli.

CONCLUSIONS

The anxiety associated with WS appears to be intimately related to reduced autonomic arousal to angry social stimuli, which may also be linked to the characteristic social disinhibition.

Processing of stimulus content but not of emotional valence is altered in persons with Williams syndrome

BACKGROUND

Individuals with Williams syndrome (WS) exhibit hypersociability and may respond atypically to emotional information in social and nonsocial stimuli. It is not yet clear whether these difficulties are specific to emotional content or stimulus type. This study examined the neural processes supporting social and emotional information processing in WS.

METHOD

Visual event-related potentials were recorded in 19 adults with WS and 10 typical peers during a picture-viewing task requiring detection of smiling faces among other social and nonsocial images with positive and negative emotional content.

RESULTS

The participant groups were not significantly different in affective processing of positive and negative stimuli and perceived faces as different from nonsocial images. Participants with WS showed subtle differences in face-specific perceptual processes (e.g. face inversion, N170 lateralisation), suggesting a more feature-based processing. They also demonstrated reduced attention and arousal modulation (P3, late positive potential) in response to faces vs. nonsocial images. These differences were independent of intelligence quotient.

CONCLUSIONS

There was no evidence of greater than typical perceptual, attentional or affective processing of social information in WS. The results support the idea that altered face perception processes and not the increased salience of social stimuli or difficulties with emotion discrimination may contribute to the hypersocial phenotype in WS.

Empathic responsiveness and helping behaviours in young children with Williams syndrome

BACKGROUND

Anecdotal and caregiver reports often highlight the sociability and empathy of children with Williams syndrome (WS), a genetically based neurodevelopmental disorder characterised by a distinctive, cognitive and social phenotype. Despite these characteristics, people with WS have many difficulties navigating the social world. In this study, we investigated whether the heightened social motivation and empathy demonstrated by children with WS lead to prosocial behaviours such as instrumental helping.

METHODS

We compared 2;8 to 5;8 year olds with WS to an age-matched and developmental quotient-matched group of children with Down syndrome (DS) and an age-matched group of typically developing children, in their responses to semi-structured naturalistic situations designed to elicit empathic and helping behaviours.

RESULTS

Children with WS showed more empathic concern than both comparison groups towards a person in distress but did not differ from controls in their level of helping behaviour. Children in both the WS and DS groups consistently received higher ratings on empathy than on helpfulness, in contrast to the balanced profile shown by the typically developing children.

DISCUSSION

Findings suggest that the heightened emotional responsivity displayed by children with WS or DS does not readily translate into other forms of socially competent behaviour. The complex relations between empathy and prosocial behaviours in typical and atypical development are discussed.

Neuron density is decreased in the prefrontal cortex in Williams syndrome

Williams Syndrome (WS) is a rare neurodevelopmental disorder associated with a hemideletion in chromosome 7, which manifests a distinct behavioral phenotype characterized by a hyperaffiliative social drive, in striking contrast to the social avoidance behaviors that are common in Autism Spectrum Disorder (ASD). MRI studies have observed structural and functional abnormalities in WS cortex, including the prefrontal cortex (PFC), a region implicated in social cognition. This study utilizes the Bellugi Williams Syndrome Brain Collection, a unique resource that comprises the largest WS postmortem brain collection in existence, and is the first to quantitatively examine WS PFC cytoarchitecture. We measured neuron density in layers II/III and V/VI of five cortical areas: PFC areas BA 10 and BA 11, primary motor BA 4, primary somatosensory BA 3, and visual area BA 18 in six matched pairs of WS and typically developing (TD) controls. Neuron density in PFC was lower in WS relative to TD, with layers V/VI demonstrating the largest decrease in density, reaching statistical significance in BA 10. In contrast, BA 3 and BA 18 demonstrated a higher density in WS compared to TD, although this difference was not statistically significant. Neuron density in BA 4 was similar in WS and TD. While other cortical areas were altered in WS, prefrontal areas appeared to be most affected. Neuron density is also altered in the PFC of individuals with ASD. Together these findings suggest that the PFC is targeted in neurodevelopmental disorders associated with sociobehavioral alterations. Autism Res 2017, 10: 99-112. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

A human neurodevelopmental model for Williams syndrome

Williams syndrome is a genetic neurodevelopmental disorder characterized by an uncommon hypersociability and a mosaic of retained and compromised linguistic and cognitive abilities. Nearly all clinically diagnosed individuals with Williams syndrome lack precisely the same set of genes, with breakpoints in chromosome band 7q11.23 (refs 1-5). The contribution of specific genes to the neuroanatomical and functional alterations, leading to behavioural pathologies in humans, remains largely unexplored. Here we investigate neural progenitor cells and cortical neurons derived from Williams syndrome and typically developing induced pluripotent stem cells. Neural progenitor cells in Williams syndrome have an increased doubling time and apoptosis compared with typically developing neural progenitor cells. Using an individual with atypical Williams syndrome, we narrowed this cellular phenotype to a single gene candidate, frizzled 9 (FZD9). At the neuronal stage, layer V/VI cortical neurons derived from Williams syndrome were characterized by longer total dendrites, increased numbers of spines and synapses, aberrant calcium oscillation and altered network connectivity. Morphometric alterations observed in neurons from Williams syndrome were validated after Golgi staining of post-mortem layer V/VI cortical neurons. This model of human induced pluripotent stem cells fills the current knowledge gap in the cellular biology of Williams syndrome and could lead to further insights into the molecular mechanism underlying the disorder and the human social brain.

Surface-based morphometry reveals distinct cortical thickness and surface area profiles in Williams syndrome

Morphometric investigations of brain volumes in Williams syndrome (WS) consistently show significant reductions in gray matter volume compared to controls. Cortical thickness (CT) and surface area (SA) are two constituent parts of cortical gray matter volume that are considered genetically distinguishable features of brain morphology. Yet, little is known about the independent contribution of cortical CT and SA to these volumetric differences in WS. Thus, our objectives were: (i) to evaluate whether the microdeletion in chromosome 7 associated with WS has a distinct effect on CT and SA, and (ii) to evaluate age-related variations in CT and SA within WS. We compared CT and SA values in 44 individuals with WS to 49 age- and sex-matched typically developing controls. Between-group differences in CT and SA were evaluated across two age groups: young (age range 6.6-18.9 years), and adults (age range 20.2-51.5 years). Overall, we found contrasting effects of WS on cortical thickness (increases) and surface area (decreases). With respect to brain topography, the between-group pattern of CT differences showed a scattered pattern while the between-group surface area pattern was widely distributed throughout the brain. In the adult subgroup, we observed a cluster of increases in cortical thickness in WS across the brain that was not observed in the young subgroup. Our findings suggest that extensive early reductions in surface area are the driving force for the overall reduction in brain volume in WS. The age-related cortical thickness findings might reflect delayed or even arrested development of specific brain regions in WS.

Mother-Child Interaction as a Window to a Unique Social Phenotype in 22q11.2 Deletion Syndrome and in Williams Syndrome

Mother-child interactions in 22q11.2 Deletion syndrome (22q11.2DS) and Williams syndrome (WS) were coded for maternal sensitivity/intrusiveness, child's expression of affect, levels of engagement, and dyadic reciprocity. WS children were found to express more positive emotions towards their mothers compared to 22q11.2DS children and those with developmental delay in a conflict interaction. During the same interaction, dyads of 22q11.2DS children were characterized by higher levels of maternal intrusiveness, lower levels of child's engagement and reduced reciprocity compared to dyads of typically developing children. Finally, 22q11.2DS children with the COMT Met allele showed less adaptive behaviors than children with the Val allele. Dyadic behaviors partially coincided with the distinct social phenotypes in these syndromes and are potential behavioral markers of psychopathological trajectory.

Joint Attention and Early Social Developmental Cascades in Neurogenetic Disorders

This review examines what is known about joint attention and early social development in three neurogenetic syndromes: Down syndrome, Williams syndrome, and fragile X syndrome. In addition, the potential cascading effects of joint attention on subsequent social development, especially social interaction and social cognition are proposed. The potential issues and complexities associated with conducting prospective, longitudinal studies of infant social development in neurogenetic disorders are discussed.

Paralinguistic abilities of adults with intellectual disability

The aim of this research was to determine the ability level of paralinguistic production and comprehension in adults with intellectual disability (ID) with regard to the level of their intellectual functioning and presence of co-morbid psychiatric conditions or dual diagnosis (DD). The sample consisted of 120 participants of both genders, ranging in age between 20 and 56 years (M=31.82, SD=8.702). Approximately 50% of the sample comprised participants with a co-existing psychiatric condition. Each of these two sub-samples (those with ID only and those with DD) consisted of 25 participants with mild ID and 35 participants with moderate ID. The paralinguistic scale from The Assessment Battery for Communication (ABaCo; Sacco et al., 2008) was used to assess the abilities of comprehension and production of paralinguistic elements. The results showed that the participants with mild ID are more successful than the participants with moderate ID both in paralinguistic comprehension tasks (p=.000) and in paralinguistic production tasks (p=.001). Additionally, the results indicated the presence of separate influences of both ID levels on all of the paralinguistic abilities (F [116]=42.549, p=.000) and the existence of DD (F [116]=18.215, p=.000).

Social functioning and autonomic nervous system sensitivity across vocal and musical emotion in Williams syndrome and autism spectrum disorder

Both Williams syndrome (WS) and autism spectrum disorders (ASD) are associated with unusual auditory phenotypes with respect to processing vocal and musical stimuli, which may be shaped by the atypical social profiles that characterize the syndromes. Autonomic nervous system (ANS) reactivity to vocal and musical emotional stimuli was examined in 12 children with WS, 17 children with ASD, and 20 typically developing (TD) children, and related to their level of social functioning. The results of this small-scale study showed that after controlling for between-group differences in cognitive ability, all groups showed similar emotion identification performance across conditions. Additionally, in ASD, lower autonomic reactivity to human voice, and in TD, to musical emotion, was related to more normal social functioning. Compared to TD, both clinical groups showed increased arousal to vocalizations. A further result highlighted uniquely increased arousal to music in WS, contrasted with a decrease in arousal in ASD and TD. The ASD and WS groups exhibited arousal patterns suggestive of diminished habituation to the auditory stimuli. The results are discussed in the context of the clinical presentation of WS and ASD.

Reasoning About Trust Among Individuals With Williams Syndrome

The present study examines whether individuals with Williams syndrome (WS) might indiscriminately trust in others, as is suggested by their strong tendency to approach and interact with strangers. To assess this possibility, adults with WS (N=22) and typical development (N=25) were asked to reason about the trustworthiness of people who lie to avoid getting in trouble versus to avoid hurting others' feelings. Findings indicated that participants with WS distrusted both types of liars and made little distinction between them. These results suggest that the high level of social approach behavior in individuals with WS cannot be explained in terms of indiscriminate trust.

Autonomic response to approachability characteristics, approach behavior, and social functioning in Williams syndrome

Williams syndrome (WS) is a neurogenetic disorder that is saliently characterized by a unique social phenotype, most notably associated with a dramatically increased affinity and approachability toward unfamiliar people. Despite a recent proliferation of studies into the social profile of WS, the underpinnings of the pro-social predisposition are poorly understood. To this end, the present study was aimed at elucidating approach behavior of individuals with WS contrasted with typical development (TD) by employing a multidimensional design combining measures of autonomic arousal, social functioning, and two levels of approach evaluations. Given previous evidence suggesting that approach behaviors of individuals with WS are driven by a desire for social closeness, approachability tendencies were probed across two levels of social interaction: talking versus befriending. The main results indicated that while overall level of approachability did not differ between groups, an important qualitative between-group difference emerged across the two social interaction contexts: whereas individuals with WS demonstrated a similar willingness to approach strangers across both experimental conditions, TD individuals were significantly more willing to talk to than to befriend strangers. In WS, high approachability to positive faces across both social interaction levels was further associated with more normal social functioning. A novel finding linked autonomic responses with willingness to befriend negative faces in the WS group: elevated autonomic responsivity was associated with increased affiliation to negative face stimuli, which may represent an autonomic correlate of approach behavior in WS. Implications for underlying organization of the social brain are discussed.

Morphological differences in the mirror neuron system in Williams syndrome

Williams syndrome (WS) is a genetic condition characterized by an overly gregarious personality, including high empathetic concern for others. Although seemingly disparate from the profile of autism spectrum disorder (ASD), both are associated with deficits in social communication/cognition. Notably, the mirror neuron system (MNS) has been implicated in social dysfunction for ASD; yet, the integrity of this network and its association with social functioning in WS remains unknown. Magnetic resonance imaging (MRI) methods were used to examine the structural integrity of the MNS of adults with WS versus typically developing (TD) individuals. The Social Responsiveness Scale (SRS), a tool typically used to screen for social features of ASD, was also employed to assess the relationships between social functioning with the MNS morphology in WS participants. WS individuals showed reduced cortical surface area of MNS substrates yet relatively preserved cortical thickness as compared to TD adults. Increased cortical thickness of the inferior parietal lobule (IPL) was associated with increased deficits in social communication, social awareness, social cognition, and autistic mannerisms. However, social motivation was not related to anatomical features of the MNS. Our findings indicate that social deficits typical to both ASD and WS may be attributed to an aberrant MNS, whereas the unusual social drive marked in WS is subserved by substrates distinct from this network.

Patterns of Sensitivity to Emotion in Children with Williams Syndrome and Autism: Relations Between Autonomic Nervous System Reactivity and Social Functioning

Williams syndrome (WS) and autism spectrum disorder (ASD) are associated with atypical social-emotional functioning. Affective visual stimuli were used to assess autonomic reactivity and emotion identification, and the social responsiveness scale was used to determine the level social functioning in children with WS and ASD contrasted with typical development (TD), to examine syndrome-specific and syndrome-general features. Children with ASD exhibited the highest arousal in response to faces, with a lack of difference in autonomic sensitivity across different emotional expressions, unlike in WS and TD. The WS group demonstrated unique deficits in identifying neutral stimuli. While autonomic responsivity to neutral faces was associated with social functioning in all children, converging profiles characterized children with WS contrasted with TD and ASD.

Intracisternal Gtf2i Gene Therapy Ameliorates Deficits in Cognition and Synaptic Plasticity of a Mouse Model of Williams-Beuren Syndrome

Williams-Beuren syndrome (WBS) is a neurodevelopmental disorder caused by a heterozygous deletion of 26-28 genes at chromosome band 7q11.23. Haploinsufficiency at GTF2I has been shown to play a major role in the neurobehavioral phenotype. By characterizing the neuronal architecture in four animal models with intragenic, partial, and complete deletions of the WBS critical interval (ΔGtf2i(+/-), ΔGtf2i( -/-), PD, and CD), we clarify the involvement of Gtf2i in neurocognitive features. All mutant mice showed hypersociability, impaired motor learning and coordination, and altered anxiety-like behavior. Dendritic length was decreased in the CA1 of ΔGtf2i(+/-), ΔGtf2i ( -/-), and CD mice. Spine density was reduced, and spines were shorter in ΔGtf2i ( -/-), PD, and CD mice. Overexpression of Pik3r1 and downregulation of Bdnf were observed in ΔGtf2i(+/-), PD, and CD mice. Intracisternal Gtf2i-gene therapy in CD mice using adeno-associated virus resulted in increased mGtf2i expression and normalization of Bdnf levels, along with beneficial effects in motor coordination, sociability, and anxiety, despite no significant changes in neuronal architecture. Our findings further indicate that Gtf2i haploinsufficiency plays an important role in the neurodevelopmental and cognitive abnormalities of WBS and that it is possible to rescue part of this neurocognitive phenotype by restoring Gtf2i expression levels in specific brain areas.

Relations between social-perceptual ability in multi- and unisensory contexts, autonomic reactivity, and social functioning in individuals with Williams syndrome

Compromised social-perceptual ability has been proposed to contribute to social dysfunction in neurodevelopmental disorders. While such impairments have been identified in Williams syndrome (WS), little is known about emotion processing in auditory and multisensory contexts. Employing a multidimensional approach, individuals with WS and typical development (TD) were tested for emotion identification across fearful, happy, and angry multisensory and unisensory face and voice stimuli. Autonomic responses were monitored in response to unimodal emotion. The WS group was administered an inventory of social functioning. Behaviorally, individuals with WS relative to TD demonstrated impaired processing of unimodal vocalizations and emotionally incongruent audiovisual compounds, reflecting a generalized deficit in social-auditory processing in WS. The TD group outperformed their counterparts with WS in identifying negative (fearful and angry) emotion, with similar between-group performance with happy stimuli. Mirroring this pattern, electrodermal activity (EDA) responses to the emotional content of the stimuli indicated that whereas those with WS showed the highest arousal to happy, and lowest arousal to fearful stimuli, the TD participants demonstrated the contrasting pattern. In WS, more normal social functioning was related to higher autonomic arousal to facial expressions. Implications for underlying neural architecture and emotional functions are discussed.

Oxytocin, vasopressin, and Williams syndrome: epigenetic effects on abnormal social behavior

Williams syndrome (WS) is a condition caused by a deletion of ∼26-28 genes on chromosome 7q11.23 often characterized by abnormal social behavior and disrupted oxytocin (OT) and vasopressin (AVP) functioning. The observation that individuals with WS exhibit OT and AVP dysregulation is compelling. There is currently a lack of evidence that any of the genes typically deleted in WS have any direct effect on either OT or AVP. In this perspective article, we present a novel epigenetic model describing how DNA methylation may impact the expression of key genes within the OT and AVP systems, which may ultimately influence the social behavior observed in WS. We draw support from data pooled from a prior empirical research study (Henrichsen et al., 2011), demonstrating that OXTR is overexpressed in WS. These preliminary findings may create new opportunities to target the OT and AVP systems with the specific goal of improving outcomes in WS and other psychiatric conditions.