Executive neuropsychological functioning in individuals with Williams syndrome

Friendships in Children with Williams Syndrome: Parent and Child Perspectives

Although children with Williams syndrome (WS) are strongly socially motivated, many have friendship difficulties. The parents of 21 children with WS and 20 of the children themselves participated in a semi-structured interview about the children's friendships. Parents reported that their child had difficulties sustaining friendships and low levels of interaction with peers. Barriers to friendships included difficulties with play and self-regulating behaviour. However, there was within-group variability, with a small number of children reported to have strong friendships. While parents reported friendship challenges, all of the children named at least one friend, and most said that they had never felt excluded by their peers. Future research is needed to determine optimal ways to support children with WS in their friendships.

Quality of life of Brazilian families who have children with Williams syndrome

This cross-sectional and descriptive study examined the family quality of life (FQoL) among 72 Brazilian families who have children with Williams syndrome, a rare genetic disorder in which most individuals have an intellectual disability, usually mild. Data were collected using sociodemographic and clinical data forms and the Beach Center FQoL Scale. The overall FQoL score was 3.90 ± 0.45, below the limit of four points considered satisfactory. Families felt more satisfied with the family interaction (4.11 ± 0.57), parenting (4.07 ± 0.42), and disability-related support (3.94 ± 0.62) domains, and less satisfied with the family's emotional (3.49 ± 0.73) and physical/material well-being (3.73 ± 0.74) domains. Paternal education, children's cardiopathy and autonomy in activities of daily living explained 24.5% of the variance in the overall FQoL. Measures are necessary to improve the emotional and physical/material well-being of families to reduce the family burden. Monitoring the child's cardiac condition and promoting independence in activities of daily living are also the main procedures.

Neurophysiological Correlates of Dynamic Beat Tracking in Individuals With Williams Syndrome

BACKGROUND

Williams syndrome (WS) is a neurodevelopmental disorder characterized by hypersociability, heightened auditory sensitivities, attention deficits, and strong musical interests despite differences in musical skills. Behavioral studies have reported that individuals with WS exhibit variable beat and rhythm perception skills.

METHODS

We sought to investigate the neural basis of beat tracking in individuals with WS using electroencephalography. Twenty-seven adults with WS and 16 age-matched, typically developing control subjects passively listened to musical rhythms with accents on either the first or second tone of the repeating pattern, leading to distinct beat percepts.

RESULTS

Consistent with the role of beta and gamma oscillations in rhythm processing, individuals with WS and typically developing control subjects showed strong evoked neural activity in both the beta (13-30 Hz) and gamma (31-55 Hz) frequency bands in response to beat onsets. This neural response was somewhat more distributed across the scalp for individuals with WS. Compared with typically developing control subjects, individuals with WS exhibited significantly greater amplitude of auditory evoked potentials (P1-N1-P2 complex) and modulations in evoked alpha (8-12 Hz) activity, reflective of sensory and attentional processes. Individuals with WS also exhibited markedly stable neural responses over the course of the experiment, and these responses were significantly more stable than those of control subjects.

CONCLUSIONS

These results provide neurophysiological evidence for dynamic beat tracking in WS and coincide with the atypical auditory phenotype and attentional difficulties seen in this population.

NIH Toolbox Cognition Battery Feasibility in Individuals With Williams Syndrome

The NIH Toolbox Cognition Battery (NIHTB-CB) was developed for epidemiological and longitudinal studies across a wide age span. Such a tool may be useful for intervention trials in conditions characterized by intellectual disability (ID), such as Williams syndrome (WS). Three NIHTB-CB tasks, including two executive functioning (Flanker, Dimensional Change Card Sort) and one episodic memory (Picture Sequence Memory) task, were given to 47 individuals with WS, ages 4 to 50, to evaluate feasibility (i.e., proportion of valid administrations) in this population. Findings indicated that NIHTB-CB tests showed good feasibility. Flanker and DCCS age-corrected scores were negatively correlated with age and showed floor effects, indicating these scores may not be useful for quantifying performance on these NIHTB-CB tests in ID.

Dissociation of early and late face-related processes in autism spectrum disorder and Williams syndrome

Background

Williams syndrome (WS) and Autism Spectrum Disorders (ASD) are neurodevelopmental conditions associated with atypical but opposite face-to-face interactions patterns: WS patients overly stare at others, ASD individuals escape eye contact. Whether these behaviors result from dissociable visual processes within the occipito-temporal pathways is unknown.

Using high-density electroencephalography, multivariate signal processing algorithms and a protocol designed to identify and extract evoked activities sensitive to facial cues, we investigated how WS (N = 14), ASD (N = 14) and neurotypical subjects (N = 14) decode the information content of a face stimulus.

Results

We found two neural components in neurotypical participants, both strongest when the eye region was projected onto the subject's fovea, simulating a direct eye contact situation, and weakest over more distant regions, reaching a minimum when the focused region was outside the stimulus face. The first component peaks at 170 ms, an early signal known to be implicated in low-level face features. The second is identified later, 260 ms post-stimulus onset and is implicated in decoding salient face social cues.

Remarkably, both components were found distinctly impaired and preserved in WS and ASD. In WS, we could weakly decode the 170 ms signal based on our regressor relative to facial features, probably due to their relatively poor ability to process faces’ morphology, while the late 260 ms component was highly significant. The reverse pattern was observed in ASD participants who showed neurotypical like early 170 ms evoked activity but impaired late evoked 260 ms signal.

Conclusions

Our study reveals a dissociation between WS and ASD patients and points at different neural origins for their social impairments.

Neuropsychological intervention in attention and visuospatial skills in two patients with Williams syndrome with different types of genetic deletion

Williams Syndrome (WS) is a neurodevelopmental disorder with a distinctive physical, cognitive, and behavioral profile caused by a microdeletion in the q11.23 region of chromosome 7. The neuropsychological profile of WS is characterized by intellectual disability, hypersociability, and deficits, especially in attention and visuospatial skills. Our objective was to assess the effectiveness of a neuropsychological intervention program in attention and visuospatial skills in two patients with WS (aged 7 and 13 years old) with different types of deletion (1.5 and 1.8 Mb). Cognitive, behavioral, and adaptive abilities were evaluated through various neuropsychological tests and scales; the neuropsychological intervention program was subsequently applied, and we assessed its effectiveness. Both patients initially presented significant deficits in attention and visuospatial skills. After the program, we found improvements in attention and visuospatial skills. In addition, both patients had significant clinical advances and changes in adaptive behaviors (social and self-care). These findings suggest that this intervention program could improve attention processes, visuospatial skills, and some aspects of adaptive behavior in patients with WS, regardless of deletion size. Although the sample was small, limiting the generalizability of the results, we believe this program could be a helpful resource for professionals working with individuals with WS.

Autism and Williams syndrome: Dissimilar socio-cognitive profiles with similar patterns of abnormal gene expression in the blood

LAY ABSTRACT

Autism spectrum disorders and Williams syndrome are complex cognitive conditions exhibiting quite opposite features in the social domain: whereas people with autism spectrum disorders are mostly hyposocial, subjects with Williams syndrome are usually reported as hypersocial. At the same time, autism spectrum disorders and Williams syndrome share some common underlying behavioral and cognitive deficits. It is not clear, however, which genes account for the attested differences (and similarities) in the socio-cognitive domain. In this article, we adopted a comparative molecular approach and looked for genes that might be differentially (or similarly) regulated in the blood of people with these conditions. We found a significant overlap between genes dysregulated in the blood of patients compared to neurotypical controls, with most of them being upregulated or, in some cases, downregulated. Still, genes with similar expression trends can exhibit quantitative differences between conditions, with most of them being more dysregulated in Williams syndrome than in autism spectrum disorders. Differentially expressed genes are involved in aspects of brain development and function (particularly dendritogenesis) and are expressed in brain areas (particularly the cerebellum, the thalamus, and the striatum) of relevance for the autism spectrum disorder and the Williams syndrome etiopathogenesis. Overall, these genes emerge as promising candidates for the similarities and differences between the autism spectrum disorder and the Williams syndrome socio-cognitive profiles.

Feasibility and acceptability of an online response inhibition cognitive training program for youth with Williams syndrome

Williams syndrome (WS) is a genetic neurodevelopmental disorder often accompanied by inhibitory difficulties. Online cognitive training programs show promise for improving cognitive functions. No such interventions have been developed for individuals with WS, but to explore the practicality of large-scale online cognitive training for this population, we must first investigate whether families of those with WS find these programs feasible and acceptable. Twenty individuals aged 10-17 years with WS, along with parents, participated in a pilot online cognitive training program supervised in real time using videoconference software. We evaluated the feasibility and acceptability of this response inhibition training using three parent questionnaires. Descriptive data are reported for the measures of feasibility and acceptability. Overall, the online procedures received a positive reaction from families. Parents were likely to recommend the study to others. They indicated training was ethical and acceptable despite feeling neutral about effectiveness. The frequency and duration of sessions were acceptable to families (two 20-to-30-min sessions per week; 10 sessions total). Families provided feedback and offered suggestions for improvement, such as more flexibility in scheduling and decreasing time spent in review of procedures.

Autism and Williams syndrome: truly mirror conditions in the socio-cognitive domain?

Autism Spectrum Disorders (ASD) and Williams Syndrome (WS) are frequently characterized as mirror conditions in the socio-cognitive domain, with ASD entailing restrictive social interests and with WS exhibiting hypersociability. In this review paper, we examine in detail the strong points and deficits of people with ASD or WS in the socio-cognitive domain and show that both conditions also share some common features. Moreover, we explore the neurobiological basis of the social profile of ASD and WS and found a similar mixture of common affected areas and condition-specific impaired regions. We discuss these findings under the hypothesis of a continuum of the socio-cognitive abilities in humans.

Relationship Between Task-Based and Parent Report-Based Measures of Attention and Executive Function in Children with Fetal Alcohol Spectrum Disorders (FASD)

A majority of children with fetal alcohol spectrum disorders (FASD) have demonstrated attention and executive function deficits as measured by both parent report measures and performance on tasks requiring sustained levels of attention. However, prior studies have consistently reported a lack of association between parental report-based and task-based performance measures. The current study investigated whether changes in performance over time within-task (i.e., first-half versus second-half) better correspond to parental reports of executive function and temperament in children with FASD. Greater differences in split-half performance during a continuous performance task were found to be associated with higher parent-reported levels of behavioral regulation and inhibitory control. These findings suggest that within-task performance differences may more accurately reflect individual differences in executive function and temperament as measured by parental report and help to further inform the way in which cognitive processes are measured in children with FASD.

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.

Association between speech-language, general cognitive functioning and behaviour problems in individuals with Williams syndrome

BACKGROUND

Williams syndrome (WS) phenotype is described as unique and intriguing. The aim of this study was to investigate the associations between speech-language abilities, general cognitive functioning and behavioural problems in individuals with WS, considering age effects and speech-language characteristics of WS sub-groups.

METHODS

The study's participants were 26 individuals with WS and their parents. General cognitive functioning was assessed with the Wechsler Intelligence Scale. Peabody Picture Vocabulary Test, Token Test and the Cookie Theft Picture test were used as speech-language measures. Five speech-language characteristics were evaluated from a 30-min conversation (clichés, echolalia, perseverative speech, exaggerated prosody and monotone intonation). The Child Behaviour Checklist (CBCL 6-18) was used to assess behavioural problems.

RESULTS

Higher single-word receptive vocabulary and narrative vocabulary were negatively associated with CBCL T-scores for Social Problems, Aggressive Behaviour and Total Problems. Speech rate was negatively associated with the CBCL Withdrawn/Depressed T-score. Monotone intonation was associated with shy behaviour, as well as exaggerated prosody with talkative behaviour. WS with perseverative speech and exaggerated prosody presented higher scores on Thought Problems. Echolalia was significantly associated with lower Verbal IQ. No significant association was found between IQ and behaviour problems. Age-associated effects were observed only for the Aggressive Behaviour scale.

CONCLUSIONS

Associations reported in the present study may represent an insightful background for future predictive studies of speech-language, cognition and behaviour problems in WS.

Delineation of a spatial working memory profile using a non-verbal eye-tracking paradigm in young children with autism and Williams syndrome

Working memory deficits profoundly inhibit children's ability to learn. While deficits have been identified in disorders such as autism spectrum disorder (ASD) and Williams syndrome (WS), findings are equivocal, and very little is known about the nature of these deficits early in development. A major barrier to advances in this area is the availability of tasks suitable for young children with neurodevelopmental disorders who experience difficulties with following verbal instructions or who are distressed by formal testing demands. To address these issues, a novel eye-tracking paradigm was designed based on an adaptation of the classic A not B paradigm in order to examine the early foundations of spatial working memory capabilities in 26 developmentally delayed preschool children with ASD, 18 age- and IQ-matched children with WS, and 19 age-matched typically-developing (TD) children. The results revealed evidence that foundational spatial working memory performance in ASD and WS was comparable with that of TD children. Performance was associated with intellectual ability in the ASD and TD groups, but not in the WS group. Performance was not associated with adaptive behavior in any group. These findings are discussed in the context of previous research that has been largely limited to older and substantially less developmentally delayed children with these neurodevelopmental disorders.

Preserved search asymmetry in the detection of fearful faces among neutral faces in individuals with Williams syndrome revealed by measurement of both manual responses and eye tracking

BACKGROUND

Individuals with Williams syndrome (WS) exhibit an atypical social phenotype termed hypersociability. One theory accounting for hypersociability presumes an atypical function of the amygdala, which processes fear-related information. However, evidence is lacking regarding the detection mechanisms of fearful faces for individuals with WS. Here, we introduce a visual search paradigm to elucidate the mechanisms for detecting fearful faces by evaluating the search asymmetry; the reaction time when both the target and distractors were swapped was asymmetrical.

METHODS

Eye movements reflect subtle atypical attentional properties, whereas, manual responses are unable to capture atypical attentional profiles toward faces in individuals with WS. Therefore, we measured both eye movements and manual responses of individuals with WS and typically developed children and adults in visual searching for a fearful face among neutral faces or a neutral face among fearful faces. Two task measures, namely reaction time and performance accuracy, were analyzed for each stimulus as well as gaze behavior and the initial fixation onset latency.

RESULTS

Overall, reaction times in the WS group and the mentally age-matched control group were significantly longer than those in the chronologically age-matched group. We observed a search asymmetry effect in all groups: when a neutral target facial expression was presented among fearful faces, the reaction times were significantly prolonged in comparison with when a fearful target facial expression was displayed among neutral distractor faces. Furthermore, the first fixation onset latency of eye movement toward a target facial expression showed a similar tendency for manual responses.

CONCLUSIONS

Although overall responses in detecting fearful faces for individuals with WS are slower than those for control groups, search asymmetry was observed. Therefore, cognitive mechanisms underlying the detection of fearful faces seem to be typical in individuals with WS. This finding is discussed with reference to the amygdala account explaining hypersociability in individuals with WS.

An event related potential study of ihibitory and attentional control in Williams syndrome adults

The primary aim of the current study was to employ event-related potentials (ERPs) methodology to disentangle the mechanisms related to inhibitory control in older adults with Williams syndrome (WS). Eleven older adults with WS (mean age 42), 16 typically developing adults (mean age 42) and 13 typically developing children (mean age 12) participated in the study. ERPs were recorded during a three-stimulus visual oddball task, during which participants were required to make a response to a rare target stimulus embedded in a train of frequent non-target stimuli. A task-irrelevant infrequent stimulus was also present at randomised intervals during the session. The P3a latency data response related to task-irrelevant stimulus processing was delayed in WS. In addition, the early perceptual N2 amplitude was attenuated. These data are indicative of compromised early monitoring of perceptual input, accompanied by appropriate orientation of responses to task-irrelevant stimuli. However, the P3a delay suggests inefficient evaluation of the task-irrelevant stimuli. These data are discussed in terms of deficits in the disengagement of attentional processes, and the regulation of monitoring processes required for successful inhibition.

Attention Bias to Emotional Faces Varies by IQ and Anxiety in Williams Syndrome

Individuals with Williams syndrome (WS) often experience significant anxiety. A promising approach to anxiety intervention has emerged from cognitive studies of attention bias to threat. To investigate the utility of this intervention in WS, this study examined attention bias to happy and angry faces in individuals with WS (N = 46). Results showed a significant difference in attention bias patterns as a function of IQ and anxiety. Individuals with higher IQ or higher anxiety showed a significant bias toward angry, but not happy faces, whereas individuals with lower IQ or lower anxiety showed the opposite pattern. These results suggest that attention bias interventions to modify a threat bias may be most effectively targeted to anxious individuals with WS with relatively high IQ.

Cross-syndrome comparison of real-world executive functioning and problem solving using a new problem-solving questionnaire

BACKGROUND

Individuals with neurodevelopmental disorders like Williams syndrome and Down syndrome exhibit executive function impairments on experimental tasks (Lanfranchi, Jerman, Dal Pont, Alberti, & Vianello, 2010; Menghini, Addona, Costanzo, & Vicari, 2010), but the way that they use executive functioning for problem solving in everyday life has not hitherto been explored. The study aim is to understand cross-syndrome characteristics of everyday executive functioning and problem solving.

METHODS

Parents/carers of individuals with Williams syndrome (n=47) or Down syndrome (n=31) of a similar chronological age (m=17 years 4 months and 18 years respectively) as well as those of a group of younger typically developing children (n=34; m=8years 3 months) completed two questionnaires: the Behavior Rating Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 2000) and a novel Problem-Solving Questionnaire.

RESULTS

The rated likelihood of reaching a solution in a problem solving situation was lower for both syndromic groups than the typical group, and lower still for the Williams syndrome group than the Down syndrome group. The proportion of group members meeting the criterion for clinical significance on the BRIEF was also highest for the Williams syndrome group. While changing response, avoiding losing focus and maintaining perseverance were important for problem-solving success in all groups, asking for help and avoiding becoming emotional were also important for the Down syndrome and Williams syndrome groups respectively. Keeping possessions in order was a relative strength amongst BRIEF scales for the Down syndrome group.

CONCLUSION

Results suggest that individuals with Down syndrome tend to use compensatory strategies for problem solving (asking for help and potentially, keeping items well ordered), while for individuals with Williams syndrome, emotional reactions disrupt their problem-solving skills. This paper highlights the importance of identifying syndrome-specific problem-solving strengths and difficulties to improve effective functioning in everyday life.

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.

Typical visual search performance and atypical gaze behaviors in response to faces in Williams syndrome

BACKGROUND

Evidence indicates that individuals with Williams syndrome (WS) exhibit atypical attentional characteristics when viewing faces. However, the dynamics of visual attention captured by faces remain unclear, especially when explicit attentional forces are present. To clarify this, we introduced a visual search paradigm and assessed how the relative strength of visual attention captured by a face and explicit attentional control changes as search progresses.

METHODS

Participants (WS and controls) searched for a target (butterfly) within an array of distractors, which sometimes contained an upright face. We analyzed reaction time and location of the first fixation-which reflect the attentional profile at the initial stage-and fixation durations. These features represent aspects of attention at later stages of visual search. The strength of visual attention captured by faces and explicit attentional control (toward the butterfly) was characterized by the frequency of first fixations on a face or butterfly and on the duration of face or butterfly fixations.

RESULTS

Although reaction time was longer in all groups when faces were present, and visual attention was not dominated by faces in any group during the initial stages of the search, when faces were present, attention to faces dominated in the WS group during the later search stages. Furthermore, for the WS group, reaction time correlated with eye-movement measures at different stages of searching such that longer reaction times were associated with longer face-fixations, specifically at the initial stage of searching. Moreover, longer reaction times were associated with longer face-fixations at the later stages of searching, while shorter reaction times were associated with longer butterfly fixations.

CONCLUSIONS

The relative strength of attention captured by faces in people with WS is not observed at the initial stage of searching but becomes dominant as the search progresses. Furthermore, although behavioral responses are associated with some aspects of eye movements, they are not as sensitive as eye-movement measurements themselves at detecting atypical attentional characteristics in people with WS.

The Importance of Sleep: Attentional Problems in School-Aged Children With Down Syndrome and Williams Syndrome

In typically developing (TD) children, sleep problems have been associated with day-time attentional difficulties. Children with developmental disabilities often suffer with sleep and attention problems, yet their relationship is poorly understood. The present study investigated this association in school-aged children with Down syndrome (DS) and Williams syndrome (WS). Actigraphy and pulse oximetry assessed sleep and sleep-disordered breathing respectively, and attention was tested using a novel visual Continuous Performance Task (CPT).Attentional deficits were evident in both disorder groups. In the TD group, higher scores on the CPT were related to better sleep quality, higher oxyhemoglobin saturation (SpO2), and fewer desaturation events. Sleep quality, duration, and SpO2 variables were not related to CPT performance for children with DS and WS.

Characterising the Profile of Everyday Executive Functioning and Relation to IQ in Adults with Williams Syndrome: Is the BRIEF Adult Version a Valid Rating Scale?

Although there is evidence of a distinct profile of executive dysfunction in Williams syndrome (WS), a rare genetically based neurodevelopmental disorder, the utility of informant reports of everyday executive function (EF) impairments and their relation to intelligence is not yet clear. Here we aimed to evaluate the functional impact of executive dysfunction in adults with WS and to establish the validity of child and adult versions of the most commonly used rating scale for EF assessment, the Behaviour Rating Inventory of Executive Function (BRIEF). We were also interested in whether distinct components of everyday EF relate to intelligence in WS. Parent report child (BRIEF-C) and adult (BRIEF-A) ratings were collected on 20 adults with WS (aged 18.5 to 53 years), with a mean IQ of 60.95 (SD = 17.67). Neuropsychological measures of EF included: The Shape School Test (Espy, 2007); select subdomains of EF from the Woodcock-Johnson III Tests of Cognitive Abilities, Australian Adaptation (WJ III COG); and select subdomains from the Vineland Adaptive Behaviour Scales, Second Edition—Parent Survey (Vineland-II). Results showed that the BRIEF-A, but not the BRIEF-C, was the most highly correlated with neuropsychological measures of EF, suggesting that it was a valid measure of the profile of EF impairments in adults with WS. The profile of everyday EF dysfunction revealed relative impairments in monitoring, working memory, planning and organisation in WS. In addition, both neuropsychological and rating scale measures showed an association between the shifting component of EF and intelligence. These findings indicate that the BRIEF-A is a valid measure of the multidimensional nature of real-world impairments in EF, and highlight its utility as a less labor intensive and low-cost screening tool for measuring specific EF impairments that could become the focus of targeted intervention in adults with WS.

Spatial-sequential and spatial-simultaneous working memory in individuals with Williams syndrome

The aim of the present study was to compare visuospatial working memory performance in 18 individuals with Williams syndrome (WS) and 18 typically developing (TD) children matched for nonverbal mental age. Two aspects were considered: task presentation format (i.e., spatial-sequential or spatial-simultaneous), and level of attentional control (i.e., passive or active tasks). Our results showed that individuals with WS performed less well than TD children in passive spatial-simultaneous tasks, but not in passive spatial-sequential tasks. The former's performance was also worse in both active tasks. These findings suggest an impairment in the spatial-simultaneous working memory of individuals with WS, together with a more generalized difficulty in tasks requiring information storage and concurrent processing, as seen in other etiologies of intellectual disability.

Are the deficits in navigational abilities present in the Williams syndrome related to deficits in the backward inhibition?

Williams syndrome (WS) is associated with a distinct profile of relatively proficient skills within the verbal domain compared to the severe impairment of visuo-spatial processing. Abnormalities in executive functions and deficits in planning ability and spatial working memory have been described. However, to date little is known about the influence of executive function deficits on navigational abilities in WS. This study aimed at analyzing in WS individuals a specific executive function, the backward inhibition (BI) that allows individuals to flexibly adapt to continuously changing environments. A group of WS individuals and a mental age- and gender-matched group of typically developing children were subjected to three task-switching experiments requiring visuospatial or verbal material to be processed. Results showed that WS individuals exhibited clear BI deficits during visuospatial task-switching paradigms and normal BI effect during verbal task-switching paradigm. Overall, the present results suggest that the BI involvement in updating environment representations during navigation may influence WS navigational abilities.

Annual research review: Rare genotypes and childhood psychopathology--uncovering diverse developmental mechanisms of ADHD risk

BACKGROUND

Through the increased availability and sophistication of genetic testing, it is now possible to identify causal diagnoses in a growing proportion of children with neurodevelopmental disorders. In addition to developmental delay and intellectual disability, many genetic disorders are associated with high risks of psychopathology, which curtail the wellbeing of affected individuals and their families. Beyond the identification of significant clinical needs, understanding the diverse pathways from rare genetic mutations to cognitive dysfunction and emotional-behavioural disturbance has theoretical and practical utility.

METHODS

We overview (based on a strategic search of the literature) the state-of-the-art on causal mechanisms leading to one of the most common childhood behavioural diagnoses - attention deficit hyperactivity disorder (ADHD) - in the context of specific genetic disorders. We focus on new insights emerging from the mapping of causal pathways from identified genetic differences to neuronal biology, brain abnormalities, cognitive processing differences and ultimately behavioural symptoms of ADHD.

FINDINGS

First, ADHD research in the context of rare genotypes highlights the complexity of multilevel mechanisms contributing to psychopathology risk. Second, comparisons between genetic disorders associated with similar psychopathology risks can elucidate convergent or distinct mechanisms at each level of analysis, which may inform therapeutic interventions and prognosis. Third, genetic disorders provide an unparalleled opportunity to observe dynamic developmental interactions between neurocognitive risk and behavioural symptoms. Fourth, variation in expression of psychopathology risk within each genetic disorder points to putative moderating and protective factors within the genome and the environment.

CONCLUSION

A common imperative emerging within psychopathology research is the need to investigate mechanistically how developmental trajectories converge or diverge between and within genotype-defined groups. Crucially, as genetic predispositions modify interaction dynamics from the outset, longitudinal research is required to understand the multi-level developmental processes that mediate symptom evolution.

Exploring spatial working memory performance in individuals with Williams syndrome: the effect of presentation format and configuration

Williams syndrome (WS) is a neurodevelopmental disorder associated with an impaired capacity for visuospatial representation. Individuals with WS have a specific weakness in spatial processing, while visual components are relatively well preserved. This dissociation is apparent in working memory function too. The present study aimed to further investigate spatial working memory performance in individuals with WS, analyzing whether their impaired WM performance regards both simultaneous and sequential spatial formats, and whether presenting configurations differently might reduce their difficulties. These issues were examined by administering simultaneous and sequential spatial tasks, in which the information to be recalled was presented in random or arranged configurations. Our results showed that individuals with WS performed less well than typically developing (TD) children in the spatial-simultaneous task, but not in the spatial-sequential one. The presence of a pattern enhanced the performance of both groups, but the difference between the two groups' performance in the spatial simultaneous task remained, albeit to a lesser degree.

Music lessons are associated with increased verbal memory in individuals with Williams syndrome

Williams syndrome (WS) is a genetic disorder characterized by intellectual delay and an affinity for music. It has been previously shown that familiar music can enhance verbal memory in individuals with WS who have had music training. There is also evidence that unfamiliar, or novel, music may also improve cognitive recall. This study was designed to examine if a novel melody could also enhance verbal memory in individuals with WS, and to more fully characterize music training in this population. We presented spoken or sung sentences that described an animal and its group name to 44 individuals with WS, and then tested their immediate and delayed memory using both recall and multiple choice formats. Those with formal music training (average duration of training 4½ years) scored significantly higher on both the spoken and sung recall items, as well as on the spoken multiple choice items, than those with no music training. Music therapy, music enjoyment, age, and Verbal IQ did not impact performance on the memory tasks. These findings provide further evidence that formal music lessons may impact the neurological pathways associated with verbal memory in individuals with WS, consistent with findings in typically developing individuals.

Williams syndrome: a surprising deficit in oromotor praxis in a population with proficient language production

Williams Syndrome (WS) is a neurodevelopmental disorder of known genetic origin, characterized by serious delays in language onset yet relatively verbose, intelligible and fluent speech in late childhood and adulthood. How do motor abilities relate to language in this group? We investigated planning and co-ordination of the movement of the speech articulators (oromotor praxis) in 28 fluent-speaking individuals with WS, aged between 12 and 30 years. Results indicate that, despite their fluent language, oromotor praxis was impaired in WS relative to two groups of typically-developing children, matched on either vocabulary or visuospatial ability. These findings suggest that the ability to plan, co-ordinate and execute complex sensorimotor movements contribute to an explanation of the delay in expressive language early in development in this neurodevelopmental disorder. In the discussion, we turn to more general issues of how individual variation in oromotor praxis may account for differences in speech/language production abilities across developmental language disorders.

Concrete and relational vocabulary: comparison between Williams and Smith-Magenis syndromes

We compared the performance of two clinical groups, Williams syndrome (WS) and Smith-Magenis syndrome (SMS), in terms of concrete and relational vocabulary. We analyzed (a) whether the WS group had an advantage in concrete vocabulary when compared to the SMS group, as good concrete vocabulary knowledge is considered a hallmark of WS; (b) if spatial processing difficulties in WS would be reflected specifically in their knowledge of relational spatial vocabulary; (c) if a specific vocabulary profile could be outlined for SMS. Our results show similar performances on receptive concrete and relational vocabulary in both groups. However, and as anticipated, performance on relational space concepts was significantly lower in the WS group.

Deeper processing is beneficial during episodic memory encoding for adults with Williams syndrome

Previous research exploring declarative memory in Williams syndrome (WS) has revealed impairment in the processing of episodic information accompanied by a relative strength in semantic ability. The aim of the current study was to extend this literature by examining how relatively spared semantic memory may support episodic remembering. Using a level of processing paradigm, older adults with WS (aged 35-61 years) were compared to typical adults of the same chronological age and typically developing children matched for verbal ability. In the study phase, pictures were encoded using either a deep (decide if a picture belongs to a particular category) or shallow (perceptual based processing) memory strategy. Behavioural indices (reaction time and accuracy) at retrieval were suggestive of an overall difficulty in episodic memory for WS adults. Interestingly, however, semantic support was evident with a greater recall of items encoded with deep compared to shallow processing, indicative of an ability to employ semantic encoding strategies to maximise the strength of the memory trace created. Unlike individuals with autism who find semantic elaboration strategies problematic, the pattern of findings reported here suggests in those domains that are relatively impaired in WS, support can be recruited from relatively spared cognitive processes.

Cerebral and cerebellar MRI volumes in Williams syndrome

Individuals with Williams syndrome (WS) present a set of cognitive, affective and motor symptoms that resemble those of patients with lesions to the cerebellum. Although there is some evidence for overall structural alterations in this brain region in WS, explorations on cerebellar white matter and cerebellar cortex volumes remain rather neglected. We aimed to compare absolute and relative cerebellar volumes, as well as patterns of white matter to cortex volumes in this brain region, between a group of individuals with WS and a group of healthy controls. T1-weighted magnetic resonance images were acquired in 17 individuals with WS and in 15 typically developing individuals. Our results showed that even though individuals from the clinical group had significantly smaller cerebrums (and cerebellums), cerebellar volumes relative to intracranial volumes were significantly enlarged. In addition, while gray matter was relatively spared and white matter disproportionately reduced in the cerebrum in WS, relative cerebellar cortex and white matter volumes were preserved. These findings support the hypothesis that volume alterations in the cerebellum are associated with the cognitive, affective and motor profiles in WS.

Neuropsychiatric and behavioral profiles of 2 adults with williams syndrome: response to antidepressant intake

BACKGROUND

Individuals with Williams syndrome, a rare genetic disorder, are characterized by specific medical, cognitive, and behavioral phenotypes and often have high anxiety levels as well as phobia. Studies of the psychiatric phenotype in adults affected by Williams syndrome or literature on the management of their mental pathologies are lacking.

METHOD

In this article, we report the neuropsychiatric profile of 2 adult patients with Williams syndrome who also have generalized anxiety disorder and depressive symptoms (DSM-IV-TR criteria), along with their anxiety profiles and the strategies that were adopted for pharmacologic intervention.

RESULTS

Neuropsychiatric profiles revealed a prefrontal cortex affliction that includes an alteration in executive functions. The patients had high scores for trait-anxiety and responded to treatment with a low-potency antipsychotic. A selective serotonin reuptake inhibitor (SSRI) was coadministered with the antipsychotic to alleviate the depressive symptoms. The treatment led to an improvement in self-control, mental concentration, and social skills, as well as decreased irritability and aggressiveness and stabilization of mood.

CONCLUSIONS

The combination of SSRIs and low doses of low-potency antipsychotics seems to be the most suitable medication to treat generalized anxiety disorder and related disorders in individuals with Williams syndrome. Manic reactions and increase in anxiety must be closely monitored during treatment. Control of anxiety and sleep should be a priority in these patients, even as a preventative measure.

Gait profiles as indicators of domain-specific impairments in executive control across neurodevelopmental disorders

In neurodevelopmental disorders, unique profiles of executive control and attention appear to co-occur with poor motor coordination. However, less is known about how syndrome-specific cognitive profiles interact with motor control and impact behavioural outcomes in neurodevelopmental disorders such as Williams syndrome (WS) and Down syndrome (DS). Here we aimed to examine the extent to which specific components of executive function interact with gait control when performing cognitive dual-tasks (verbal fluency, digit span) in WS and DS. Spatiotemporal gait characteristics and intra-individual variability of gait were assessed in individuals with WS who were matched on spatial ability to individuals with DS, and chronologically age (CA) matched controls. During the concurrent verbal fluency task, the WS group had greater dual-task costs on spatiotemporal gait parameters and variability than CA controls. Conversely, individuals with DS had selective gait interference during the concurrent digit span task when compared to CA controls, but only under increased demands on cognitive control where there was greater variability in step timing in DS. The interrelationships between cognitive-motor interference and behavioural measures of executive functioning appeared to differentiate between WS and DS, and emphasise the importance of task modality in unpacking the executive control profile in these neurodevelopmental disorders. These findings support the notion that associated cerebellar-cortico abnormalities may produce quite distinct profiles of executive control across cognitive and motor domains that impact on behavioural outcomes in neurodevelopmental disorders.

Subjective experience of episodic memory and metacognition: a neurodevelopmental approach

Episodic retrieval is characterized by the subjective experience of remembering. This experience enables the co-ordination of memory retrieval processes and can be acted on metacognitively. In successful retrieval, the feeling of remembering may be accompanied by recall of important contextual information. On the other hand, when people fail (or struggle) to retrieve information, other feelings, thoughts, and information may come to mind. In this review, we examine the subjective and metacognitive basis of episodic memory function from a neurodevelopmental perspective, looking at recollection paradigms (such as source memory, and the report of recollective experience) and metacognitive paradigms such as the feeling of knowing). We start by considering healthy development, and provide a brief review of the development of episodic memory, with a particular focus on the ability of children to report first-person experiences of remembering. We then consider neurodevelopmental disorders (NDDs) such as amnesia acquired in infancy, autism, Williams syndrome, Down syndrome, or 22q11.2 deletion syndrome. This review shows that different episodic processes develop at different rates, and that across a broad set of different NDDs there are various types of episodic memory impairment, each with possibly a different character. This literature is in agreement with the idea that episodic memory is a multifaceted process.

Tracking the Cognitive, Social, and Neuroanatomical Profile in Early Neurodegeneration: Type III Cockayne Syndrome

Cockayne syndrome (CS) is an autosomal recessive disease associated with premature aging, progressive multiorgan degeneration, and nervous system abnormalities including cerebral and cerebellar atrophy, brain calcifications, and white matter abnormalities. Although several clinical descriptions of CS patients have reported developmental delay and cognitive impairment with relative preservation of social skills, no previous studies have carried out a comprehensive neuropsychological and social cognition assessment. Furthermore, no previous research in individuals with CS has examined the relationship between brain atrophy and performance on neuropsychological and social cognition tests. This study describes the case of an atypical late-onset type III CS patient who exceeds the mean life expectancy of individuals with this pathology. The patient and a group of healthy controls underwent a comprehensive assessment that included multiple neuropsychological and social cognition (emotion recognition, theory of mind, and empathy) tasks. In addition, we compared the pattern of atrophy in the patient to controls and to its concordance with ERCC8 gene expression in a healthy brain. The results showed memory, language, and executive deficits that contrast with the relative preservation of social cognition skills. The cognitive profile of the patient was consistent with his pattern of global cerebral and cerebellar loss of gray matter volume (frontal structures, bilateral cerebellum, basal ganglia, temporal lobe, and occipito-temporal/occipito-parietal regions), which in turn was anatomically consistent with the ERCC8 gene expression level in a healthy donor’s brain. The study of exceptional cases, such as the one described here, is fundamental to elucidating the processes that affect the brain in premature aging diseases, and such studies provide an important source of information for understanding the problems associated with normal and pathological aging.

Attentional lapse and inhibition control in adults with Williams Syndrome

Research exploring cognitive processing associated with Williams Syndrome (WS) has suggested that executive functioning deficits exist across the developmental spectrum. Such executive functions include problem solving, planning, dividing attention and inhibiting responses. Within a framework of executive functions, the aim of the current study was to explore attentional lapse and inhibition skills in older adults with WS (n=20; aged 36-61 yr) and consider the implications of deficits within this group. Participants with WS were compared to typical adults of the same chronological age and typical older adults (aged 65+yr) to consider attentional changes seen in the ageing process. The study employed a sustained attention to response task known to assess inhibition and attentional lapse but which had not previously been used with this population. Compared to both groups of typical matches, the results indicated atypicalities of attention and inhibition in adults with WS. Specifically, compared to the typical matches, adults with WS failed to withhold a response (showing inhibition deficits), had problems re-engaging attentional control processes after making an error and showed a generalised deficit of concentration and task engagement. We conclude that further attention should be paid to the cognitive capacity of older individuals with WS in order to consider the everyday challenges faced by this group and to provide adequate intervention and support for daily living.

Using developmental trajectories to examine verbal and visuospatial short-term memory development in children and adolescents with Williams and Down syndromes

Williams (WS) and Down (DS) syndromes have been associated with specifically compromised short-term memory (STM) subsystems. Individuals with WS have shown impairments in visuospatial STM, while individuals with DS have often shown problems with the recall of verbal material. However, studies have not usually compared the development of STM skills in these domains, in these populations. The present study employed a cross-sectional developmental trajectories approach, plotting verbal and visuospatial STM performance against more general cognitive and chronological development, to investigate how the domain-specific skills of individuals with WS and DS may change as development progresses, as well as whether the difference between STM skill domains increases, in either group, as development progresses. Typically developing children, of broadly similar cognitive ability to the clinical groups, were also included. Planned between- and within-group comparisons were carried out. Individuals with WS and DS both showed the domain-specific STM weaknesses in overall performance that were expected based on the respective cognitive profiles. However, skills in both groups developed, according to general cognitive development, at similar rates to those of the TD group. In addition, no significant developmental divergence between STM domains was observed in either clinical group according to mental age or chronological age, although the general pattern of findings indicated that the influence of the latter variable across STM domains, particularly in WS, might merit further investigation.

Looking around houses: attention to a model when drawing complex shapes in Williams syndrome and typical development

Drawings by individuals with Williams syndrome (WS) typically lack cohesion. The popular hypothesis is that this is a result of excessive focus on local-level detail at the expense of global configuration. In this study, we explored a novel hypothesis that inadequate attention might underpin drawing in WS. WS and typically developing (TD) non-verbal ability matched groups copied and traced a house figure comprised of geometric shapes. The house was presented on a computer screen for 5-s periods and participants pressed a key to re-view the model. Frequency of key-presses indexed the looks to the model. The order that elements were replicated was recorded to assess hierarchisation of elements. If a lack of attention to the model explained poor drawing performance, we expected participants with WS to look less frequently to the model than TD children when copying. If a local-processing preference underpins drawing in WS, more local than global elements would be produced. Results supported the first, but not second hypothesis. The WS group looked to the model infrequently, but global, not local, parts were drawn first, scaffolding local-level details. Both groups adopted a similar order of drawing and tracing of parts, suggesting typical, although delayed strategy-use in the WS group. Additionally both groups drew larger elements of the model before smaller elements, suggested a size-bias when drawing.

Spontaneous and cued gaze-following in autism and Williams syndrome

Background

From a young age the typical development of social functioning relies upon the allocation of attention to socially relevant information, which in turn allows experience at processing such information and thus enhances social cognition. As such, research has attempted to identify the developmental processes that are derailed in some neuro-developmental disorders that impact upon social functioning. Williams syndrome (WS) and autism are disorders of development that are characterized by atypical yet divergent social phenotypes and atypicalities of attention to people.

Methods

We used eye tracking to explore how individuals with WS and autism attended to, and subsequently interpreted, an actor’s eye gaze cue within a social scene. Images were presented for 3 seconds, initially with an instruction simply to look at the picture. The images were then shown again, with the participant asked to identify the object being looked at. Allocation of eye gaze in each condition was analyzed by analysis of variance and accuracy of identification was compared with t tests.

Results

Participants with WS allocated more gaze time to face and eyes than their matched controls, both with and without being asked to identify the item being looked at; while participants with autism spent less time on face and eyes in both conditions. When cued to follow gaze, participants with WS increased gaze to the correct targets; those with autism looked more at the face and eyes but did not increase gaze to the correct targets, while continuing to look much more than their controls at implausible targets. Both groups identified fewer objects than their controls.

Conclusions

The atypicalities found are likely to be entwined with the deficits shown in interpreting social cognitive cues from the images. WS and autism are characterized by atypicalities of social attention that impact upon socio-cognitive expertise, but, importantly, the type of atypicality is syndrome specific.

Caregiver survey of pharmacotherapy to treat attention deficit/hyperactivity disorder in individuals with Williams syndrome

Williams syndrome (WS) is a genetic condition characterized by a unique neurocognitive and behavioral profile, including increased incidence of attention deficit/hyperactivity disorder (ADHD). The purpose of the present study was to examine the perceived helpfulness and side effects of medications used to treat ADHD (methylphenidate class, amphetamine class, atomoxetine) in individuals with WS. This was accomplished with a survey of parents/caregivers of individuals with WS through the Williams Syndrome Association. Five-hundred twelve (512) parents/caregivers responded to the survey regarding their child's/adult child's use of ADHD medications. Twenty-seven percent (27%) of the individuals had been prescribed a medication for ADHD, most commonly a methylphenidate class medication. OROS-methylphenidate was reported as the most helpful methylphenidate class formulation, with 74% reporting it at least somewhat helpful. Survey participants reported similar side effects as typically developing controls, but to a greater degree. Irritability was the most commonly endorsed side effect of an ADHD medication (38%). Individuals reported use of stimulant medications in the presence and absence of underlying cardiac conditions, with 56% of ADHD medication users reporting supravalvular aortic stenosis, 36% pulmonary artery stenosis, and 25% systemic hypertension. Individuals taking ADHD medications were more likely to report dental problems (p=0.004). Additional studies are needed to further investigate these findings and examine short-versus long-acting stimulant medications and dosage effects.

Attribution of negative intention in Williams syndrome

People with Williams syndrome (WS) are said to have sociable and extremely trusting personalities, approaching strangers without hesitation. This study investigated whether people with WS are less likely than controls to attribute negative intent to others when interpreting a series of ambiguous pictures. This may, at least partially, explain their hypersociability toward strangers. Twenty-seven individuals with WS and 54 typically developing controls (27 matched to WS participants on sex and chronological age and 27 matched on sex and mental age) viewed 10 ambiguous pictures, where one person in the picture may be seen as having a negative objective. Participants were asked to describe what was happening in the picture. Responses were scored for negative intention attribution (NIA). NIA was reduced in WS individuals relative to typically developing controls of the same chronological age, but was similar to typically developing controls of the same mental age. Findings are discussed in relation to possible underlying neurological and cognitive mechanisms and practical implications for understanding and teaching stranger danger to people with WS.

Executive functions in intellectual disabilities: a comparison between Williams syndrome and Down syndrome

Executive functions are a set of high cognitive abilities that control and regulate other functions and behaviors and are crucial for successful adaptation. Deficits in executive functions are frequently described in developmental disorders, which are characterized by disadaptive behavior. However, executive functions are not widely examined in individuals with intellectual disability. The present study is aimed at evaluating the etiological specificity hypotheses pertaining to executive functions by comparing individuals with intellectual disability of different etiology, as Williams syndrome and Down syndrome, on different aspects of executive functions. To this aim a battery evaluating attention, short-term and working memory, planning, categorization, shifting and inhibition, was administered to 15 children, adolescents and adults with Williams syndrome, to 15 children, adolescents and adults with Down syndrome and to 16 mental-age-matched typically developing children. The two groups with intellectual disability showed impairment in a set of executive functions, as auditory sustained attention, visual selective attention, visual categorization and working memory, and preserved visual sustained attention, auditory selective attention and visual inhibition. However, a distinctive profile has been found between the two syndromic groups on other executive functions. While participants with Down syndrome were poor in shifting and verbal aspects of memory and inhibition, those with Williams syndrome were poor in planning. The specific weakness and straights on executive functions may support the etiological specificity hypothesis accounting for distinctive cognitive development syndrome-specific.

Executive function in Williams and Down syndromes

Williams (WS) and Down (DS) syndromes are characterised by roughly opposing ability profiles. Relative verbal strengths and visuospatial difficulties have been reported in those with WS, while expressive language difficulties have been observed in individuals with DS. Few investigations into the executive function (EF) skills of these groups have examined the effect of verbal/visuospatial task type on performance. Analogous verbal and visuospatial measures were administered to these populations within four EF domains: executive-loaded working memory (ELWM), inhibition, fluency and set-shifting. Performance in both groups was compared to that of typically developing (TD) children using regression techniques controlling for potentially influential cognitive/developmental factors. Individuals with WS showed the expected relative visuospatial difficulties, as indicated by poorer performance than TD individuals, on tests of ELWM and fluency. Individuals with DS displayed the expected relative verbal difficulty in the domain of set-shifting. In addition, each population showed pervasive deficits across modality in one domain; ELWM for individuals with DS, and inhibition for individuals with WS. Individuals with WS and DS showed EF difficulties in comparison to a TD group, but, their executive performance was affected by EF task type (verbal/visuospatial) and EF domain in different ways. While the findings indicated that EF in these populations is characterised by a range of specific strengths and weaknesses, it was also suggested that the relative verbal/visuospatial strengths associated with each population do not consistently manifest across EF domains. Lastly, syndrome specificity was indicated by the differences in groups' performance patterns.

Gaze aversion during social style interactions in autism spectrum disorder and Williams syndrome

During face-to-face interactions typically developing individuals use gaze aversion (GA), away from their questioner, when thinking. GA is also used when individuals with autism (ASD) and Williams syndrome (WS) are thinking during question-answer interactions. We investigated GA strategies during face-to-face social style interactions with familiar and unfamiliar interlocutors. Participants with WS and ASD used overall typical amounts/patterns of GA with all participants looking away most while thinking and remembering (in contrast to listening and speaking). However there were a couple of specific disorder related differences: participants with WS looked away less when thinking and interacting with unfamiliar interlocutors; in typical development and WS familiarity was associated with reduced gaze aversion, however no such difference was evident in ASD. Results inform typical/atypical social and cognitive phenotypes. We conclude that gaze aversion serves some common functions in typical and atypical development in terms of managing the cognitive and social load of interactions. There are some specific idiosyncracies associated with managing familiarity in ASD and WS with elevated sociability with unfamiliar others in WS and a lack of differentiation to interlocutor familiarity in ASD. Regardless of the familiarity of the interlocutor, GA is associated with thinking for typically developing as well as atypically developing groups. Social skills training must take this into account.