Anxiety in Williams Syndrome: The Role of Social Behaviour, Executive Functions and Change Over Time
Anxiety in Williams Syndrome: The Role of Social Behaviour, Executive Functions and Change Over Time
Elise Ng‑Cordell 0 1 2 3
Mary Hanley 0 1 2 3
Alyssa Kelly 0 1 2 3
Deborah M. Riby 0 1 2 3
0 Present Address: Department of Experimental Psychology, University of Oxford , Oxford , UK
1 Psychology Department , Science Laboratories , Durham University , South Road, Durham DH1 3LE , UK
2 Department of Psychology, Durham University , Durham , UK
3 Centre for Developmental Disorders, Durham University , Durham , UK
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; Anxiety; Longitudinal; Social functioning; Executive function
Williams syndrome (WS) is a sporadically occurring,
relatively rare, developmental disorder caused by a hemizygous
deletion of approximately 25–28 genes on chromosome
(Hillier et al. 2003)
. It has a reported prevalence
(Korenberg et al. 2003, but see also 1:7,500;
Strømme et al. 2002)
, and affects males and females equally.
WS is associated with a distinctive profile of medical,
physical, cognitive and behavioural characteristics. For example,
individuals with WS can have medical difficulties including
heart problems (supravalvular aortic stenosis),
hypercalcemia, musculoskeletal abnormalities, and distinctive facial
.While there is considerable
variability of intellectual functioning, most individuals with
WS have mild to moderate cognitive impairments
et al. 2000)
. Behaviourally, individuals with WS tend to be
very friendly and empathetic, and have often been described
(Jones et al. 2000)
. In more recent years
there has been a focus on the social atypicalities
et al. 2015)
and psychiatric comorbidities, such as anxiety
. Anxiety is the most prevalent mental health
concern, especially by adulthood
(e.g. Stinton et al. 2012)
However, despite this heightened prevalence, interventions
targeting anxiety are lacking
(e.g. Cherniske et al. 2004)
As future intervention strategies require a comprehensive
understanding of anxiety in WS, the present study focuses
on the phenomenology, development, and correlates of this
phenomenon. It is important to consider how anxiety might
be associated with the other characteristics of the disorder,
specifically aspects of the combined cognitive and social
Anxiety in Williams Syndrome
Alongside a socially gregarious disposition, the high
prevalence of anxiety-related psychopathology is a seemingly
paradoxical feature of WS. In a comprehensive study of
anxiety in WS, Leyfer et al. (2006) assessed the occurrence
of co-morbid psychiatric disorders in 4–16 year-olds with
WS (N = 119). Using the Anxiety Disorder Interview
(Silverman and Albano 1996)
, a structured
clinical interview for parents, they found that rates of
generalised anxiety disorder (GAD; 12%) and specific phobia
(SP; 54%) were significantly higher than observed in the
general population and those with intellectual disability.
Furthermore, rates of GAD were higher among older
individuals (11–16 years) than would be expected based on
rates in younger individuals (4–6 years), suggesting
anxiety in WS increases with age. Elsewhere, Cherniske et al.
(2004) assessed the psychiatric profiles of 20 adults with
WS. Based on diagnostic assessments by licensed
psychiatrists, 13 individuals were classified as having moderate
or severe anxiety, while three were described as having
milder, subclinical problems. Again, the most common
anxiety disorders were SP and GAD. By extending the
previous findings to an adult sample, this study further
supported the claim that anxiety is a persistent
phenomenon in WS.
The studies outlined above employed cross-sectional
designs, preventing inferences about the development of
anxiety over time. To date, there are two known
longitudinal studies of anxiety in WS. First, Woodruff-Borden et al.
(2010) used the Anxiety Disorder Interview Schedule to
assess 4–13 year-old children with WS (N = 45; mean age
6.67 years) in a two-year longitudinal study. While 60% of
their sample presented with at least one anxiety disorder
on initial assessment, this figure had increased to over 80%
by follow-up. Seventy-two per cent of those with an initial
anxiety disorder had developed an additional diagnosis at
follow-up. Thus, the frequency of additional cumulative
diagnoses suggests that in WS, anxiety generally remains
stable, and in some individuals increases over time.
Not all findings support this trend though, as Green
et al. (2012) conducted a five-year longitudinal study,
exploring rates of psychiatric disorders among 6–23
yearold children with WS (N = 38) and developmental
disabilities of mixed etiology. Using the Kiddie Schedule for
Affective Disorders and Schizophrenia
(Kaufman et al.
, they found that rates of anxiety disorders were
significantly higher in WS at both time points. However, the
WS group also showed a dramatic decrease in prevalence
rates from initial assessment (84%) to follow-up (44%).
A small proportion of the WS children in this sample
received SSRI medication over the study period, which
may have influenced outcomes. Furthermore, the average
age of the sample at initial assessment was 13 years, as
opposed to 6 years in Woodruff-Borden et al. (2010) study,
and it may be that the trajectory of anxiety changes from
childhood to adolescence. Given these differing accounts,
further longitudinal studies across a wider age range are
warranted to clarify the developmental trajectory of
anxiety in WS.
Anxiety and Social Functioning in Williams Syndrome
A defining feature of WS is the social profile, characterized
by heightened attraction to faces and a significant
motivation towards social interactions
(Jones et al. 2000; Frigerio
et al. 2006)
. Numerous reports describe people with WS as
“hypersocial” compared to those with other developmental
disorders and typically developing individuals (see
JärvinenPasley et al. 2008). However, despite strong affiliative
tendencies, individuals with WS consistently score within the
range of mild-to-moderate impairment on social reciprocity
(e.g. Kirk et al. 2013; Lough et al. 2015)
difficulties have lasting impacts on adaptive functioning
and well-being. For example, undiscerning social approach
behaviours—such as indiscriminately engaging others
without considering social cues—coupled with cognitive
impairments can increase the potential for victimization and social
(Klein-Tasman et al. 2011; Lough et al. 2015;
Jawaid et al. 2012; Riby et al. 2017)
. Furthermore, many
adults with WS are unable to maintain friendships, and
suffer from social isolation
(Howlin and Udwin 2006)
Attempts to understand the socio-emotional and
behavioural correlates of anxiety in WS have led to an emerging
body of research into the potential interplay between anxiety
and social functioning. Riby et al. (2014) measured parental
reports of anxiety using the Spence Children’s Anxiety Scale
(SCAS; Spence 1998)
—and social functioning—using the
Social Responsiveness Scale
(SRS; Constantino and
in their study of 59 individuals with WS aged
between 6 and 36 years. They found a small positive but
significant correlation between anxiety and social
functioning impairments (r = .362, p < .01). Splitting the participants
into high- and low- anxious groups revealed that highly
anxious individuals had greater impairments on the SRS
subscales social awareness, cognition, and communication,
which are said to reflect “socio-cognitive” functions
(KleinTasman et al. 2011). Interestingly, social motivation did not
differ between the groups. In other words, although both
groups were similarly motivated by social interactions, the
high-anxious individuals were less adept in socio-cognitive
domains. This does not support the idea that social
motivation serves as a protective factor against anxiety but rather
that hypersociability may mask anxiety in social situations
(Dodd et al. 2009; Dykens 2003)
. Therefore, when trying to
understand anxiety in WS it is important to account for the
role of social functioning.
Anxiety and Executive Functioning in Williams
Executive functions (EFs) have become a topic of increased
focus within the WS cognitive profile. They are a group of
higher-order cognitive processes associated with pre-frontal
circuits believed to modulate cognitive, social, and
emotional behaviours. They are widely conceptualized as a set of
separate but related constructs, including cognitive
flexibility (or shifting), inhibition, and working memory
et al. 2000)
. Several studies have found delays and
impairments across a range of EFs in WS; including inhibition,
setshifting, and working memory
(e.g. Menghini et al. 2010;
Rhodes et al. 2010)
. Furthermore, while some
developmental improvements in EF are observed during early childhood,
deficits generally persist into adulthood (Greer et al. 2013).
Evidence from typical development indicates that
executive dysfunction is associated with higher trait anxiety
(Ursache and Raver 2014)
, and moderates the relationship
between having an anxious temperament and developing
an anxiety disorder
. In a study of adults with
WS (N = 19) Rhodes et al. (2010) administered a battery of
tasks measuring attention set-shifting, planning, and
working memory abilities. They found that executive dysfunction
across these tasks was associated with parental reports of
negative affect, conduct problems, and decreased prosocial
behaviours, as measured by the Conners Parent Rating Scale
(Conners et al. 1998)
, and the Strengths and Difficulties
Elsewhere, McGrath et al. (2016) explored the
relationship between anxiety and attentional control in
individuals with WS (aged 12–56), using the SCAS and a social
dot-probe task in which participants (N = 46) were exposed
to either happy or angry faces. They reported that highly
anxious individuals displayed an increased bias towards
angry faces, which was primarily explained by an
inability to disengage, or shift attention from threatening stimuli.
They noted that as general “sticky attention” effects are
welldocumented in WS
(e.g. Riby and Hancock 2008; Riby et al.
.It is possible that a broader difficulty in
attentionshifting, coupled with hypervigilance to threat, underlies
the onset and maintenance of anxiety in this population.
In response to suggestions that performance-based EF
tasks are too reductionist
(e.g. Brown 2006)
, rating scales
such as the behaviour rating inventory of executive
functioning (BRIEF; Gioia et al. 2000) have been designed to
measure EFs with greater ecological validity, by allowing
researchers to assess regulatory abilities in everyday
(Kenworthy et al. 2008)
. So far, the BRIEF has yielded
several important findings in WS research. For example,
Woodruff-Borden et al. (2010) found that the presence of an
anxiety disorder was associated with increased behavioural
and emotional dysregulation. Moreover, this relationship
was stable over time. As the authors only reported
difficulties in broader domains of behavior and emotion regulation,
it would be interesting to build on these findings, honing in
on the specific functions associated with increased anxiety.
Pitts et al. (2016
) investigated the
association between Specific Phobia (SP—as measured by the
ADIS-P) and behavioural regulation (as measured by the
BRIEF) in their sample of children and adolescents with
WS (N = 194). Using a logistic regression model, they
found that behavioural dysregulation was the strongest
predictor of SP, with children at or above clinical levels
of dysregulation at the greatest risk for SP. The authors
proposed that impaired abilities to self-regulate or shift
attention away from threatening stimuli leads to the
subsequent development of irrational fears surrounding
specific objects or situations. While this study has important
implications for understanding some of the cognitive and
behavioural foundations of anxiety in WS, its scope is
limited as it only covers the associations between EF and
SP. As such, it is unclear whether behavioural
dysregulation confers an increased risk for both cue-specific and
more generalized forms of anxiety (such as GAD). It is
thus important to build upon this work by investigating
whether the reported relationship extends beyond
cue-specific anxiety disorders towards a broader range of anxious
Therefore, although the evidence suggests that EF
impairments are implicated in the presence of anxiety in
WS, further work is needed to address gaps in current
understanding. For example, questions remain as to the
relative contribution of different components of EF to the
development and maintenance of anxiety in WS, and the
associations to other key characteristics of WS, namely
The Current Study
In light of the above literature, the aims of this study were
two-fold. The first aim was to explore the developmental
course of anxiety in WS by looking at changes in its
presentation over time (4 years) and its association with age (in the
cross-sectional sample). Based on existing literature, anxiety
was predicted to increase over time, and with age. A second
aim was to explore how anxiety was associated with other
core features of the disorder, namely social and executive
functioning. It was predicted that most individuals with WS
would show impairments in both social and executive
functioning. Specifically, those with higher levels of anxiety were
predicted to present with more difficulties with social
functioning. We also explored whether specific aspects of
executive functioning (i.e. shift, inhibit, etc.) were differentially
associated with anxiety, although due to limited literature no
specific predictions were made. Finally, the study sought to
examine the extent to which social and executive
functioning predicted anxiety in the cross-sectional sample. As no
studies to date have measured all three aspects of the WS
psychosocial profile concurrently, no specific hypotheses
Participants were 26 parents or caregivers (25 mother,
1 older sibling) of individuals with WS who were aged
5–37 years (13 were female; 11 were under the age of 18). 21
individuals had received a genetic diagnosis via fluorescent
in situ hybridisation testing and the remaining five had been
diagnosed phenotypically on the basis of supravalvular
aortic stenosis and facial dysmorphology before the availability
of routine genetic testing. These 26 individuals are referred
to as the “cross-sectional sample” for whom parental data
Within this sample, the parents of a subset of 17 individuals,
aged 8–37 years (8 WS females) had participated in a
(“Time 1”; part but not all of the sample reported
in Riby et al. 2014)
. This group of 17 is referred to as “the
follow-up sample” for whom parental data were obtained.
Data from the parents of these 17 individuals at Time 1 and
at the current time point (“Time 2”) comprised the
followup data set1.
Data on anxiety, verbal ability
(measured using the British
Picture Vocabulary Scale II BPVS-II; Dunn et al. 1997)
non-verbal ability (measure using the Ravens coloured
progressive matrices (RCPM);
Raven et al. 1990
) were available
from Time 1. Anxiety, social functioning (measured by the
Social Responsiveness Scale 2; Constantino & Gruber, 2012,
and executive functioning
(measured by the BRIEF; Gioia
et al. 2015)
were measured at Time 2 for all 26 participants.
1 One individual had a comorbid diagnosis of ADHD. Removing this
person from the sample did not affect the pattern of results; therefore
the entire sample’s data were retained in the analyses.
The Spence Children’s Anxiety Scale—Parent Version
(SCAS-P; Spence 1998)
is a 38-item parent-report
measure that assesses symptoms of anxiety based on DSM-IV
criteria for childhood anxiety disorders (APA, 1994). It is
reported to have good internal consistency, with an alpha
coefficient of 0.92
(Spence et al. 2003)
. In the current
sample, Cronbach’s alpha for the SCAS-P was 0.833. The items
comprise six subscales–Panic/Agoraphobia, fears of physical
injuries, separation anxiety, social phobia,
obsessive–compulsive disorder, and generalized anxiety disorder. Parents
rate each item on a four-point Likert Scale (never, some‑
times, often, and always). Items are summed to produce an
overall anxiety score, where higher scores indicate greater
severity. While there are no standardized clinical cut-offs, a
total score of 24 is one standard deviation above the mean in
a community sample
(Nauta et al. 2004)
. This was used as a
cut-off point for clinical significance in previous WS studies
(Rodgers et al. 2012; Riby et al. 2014)
. For parents of
individuals over 18, an adult version of the SCAS-P was used
in which some items were adapted by wording or content to
be developmentally appropriate (for example, “other kids”
was replaced with “other people”). The adult version of the
SCAS-P retained the same structure as the original SCAS-P,
as the total number of questions, and number of questions
in each subscale, was the same across both measures. This
exact adaptation of the items for adults has previously been
used in published research
(see Dodd et al. 2009; Riby et al.
. It is not unusual for child measures used to capture
anxiety to be used with adults with WS
(see both Porter et al.
2009 and Dykens et al. 2005 for the use of other anxiety
measures designed for children but used with WS adults)
The Social Responsiveness Scale Second Edition
Constantino and Gruber 2012)
is a 65-item parent-report
measure, designed to assess impairments of social
reciprocity characteristic of ASDs. Its reported internal consistency
is high, with an alpha coefficient of 0.95
. Cronbach’s alpha in the current sample for the
SRS was 0.806. The items map onto five subscales: social
awareness, social cognition, social communication, social
motivation, and restricted interests and repetitive behaviours.
Higher scores indicate greater impairments. The SRS-2
provides two subscales corresponding with the two symptom
domains within ASDs: social communication and interaction
(SCI) and restricted and repetitive behaviour (RRB). Total
and subscale scores can be converted to T-scores, which fall
into three ranges of functioning: normal, mild-to-moderately
impaired, or severely impaired. As T scores can reduce the
spread of scores especially at higher levels of impairment,
they were used for the purpose of classification into ranges
of functioning and SRS raw scores were used for all other
(in line with Riby et al. 2014)
. For parents of
individuals under 18, the SRS-2 School-Age Form was used.
For parents of those over 18, the SRS-2 Adult Form was
administered. The total number of items, and number of
items within each subscale is consistent across both forms,
allowing for data for both adults and children to be combined
Constantino & Gruber, 2012). These data are referred to
collectively as SRS-2 data.
The Behaviour Rating Inventory of Executive Functioning
Second Version, Parent Form
(BRIEF-2; Gioia et al. 2015)
is a 63-item questionnaire for parents of 5-18-year-olds that
measures everyday EF behaviours. Internal consistency
is high across all scales and indices (all alpha coefficients
above 0.90; Gioa et al. 2015). Cronbach’s alpha in the
current sample for the BRIEF-2 was 0.949. Items map onto ten
clinical scales: inhibit, self-monitor, shift, emotional control,
initiate, task completion, working memory, plan/organize,
task-monitor, and organization of materials. The scales
comprise three indices: the Behaviour Regulation Index,
Emotion Regulation Index, and Cognitive Regulation Index. For
parents of individuals over 18, The Behaviour Rating
Inventory of Executive Functioning Adult Version, Informant
(BRIEF-A; Roth et al. 2005)
was administered, as it
is reported to be a more valid measure of EFs in adults with
(Hocking et al. 2015)
. The BRIEF-A contains the same
clinical scales as the BRIEF-2. Its reported internal
consistency is high, with alpha coefficients of 0.80–0.98
(Roth et al.
. Cronbach’s alpha for the BRIEF-A was 0.975. For the
purposes of this research, the scales Inhibit, Self-Monitor,
Shift, and Emotional Control were used, as they map onto
the Behavior and Emotion Regulation Indices.2
Combining BRIEF data
To increase power in the analyses, data from the BRIEF-2
and BRIEF-A were combined, and are referred to
collectively as BRIEF data. This was done after consulting
the authors of the manual (Isquith, personal
communication, 18th July 2016). For each clinical scale, raw scores
can be converted to T-scores, where higher scores indicate
higher levels of dysfunction. Additionally, T-scores can be
2 Inhibit measures the ability to control impulses and stop certain
behaviours at appropriate times. Self-Monitor measures the ability to
monitor the effects of one’s behaviour on others. Shift assesses the
ability to move fluidly from one situation to another, and to solve
problems flexibly. Emotional Control measures the ability to
modulate emotional responses appropriately.
classified into four ranges of function/dysfunction: T-scores
up to 59 indicate a normal level of functioning, between
60 and 64 indicate mildly elevated levels of dysfunction,
between 65 and 69 indicate potentially clinically elevated
levels, and at or above 70 indicate clinically elevated
levels. As the number of items relating to each subscale differs
between the BRIEF-2 and BRIEF-A, T-scores were used
(instead of raw scores) for both categorization and analysis.
The project received ethical approval from the local ethics
committee. Participants were families with a child with
Williams Syndrome in Ireland and Northern Ireland and were
recruited through the Williams Syndrome Association of
Ireland and the Williams Syndrome Foundation UK.
Parents wishing to participate opted in voluntarily to the
project by signing an informed consent form, and were given a
questionnaire pack with a stamped addressed envelope for
return. A debrief sheet was attached for parents to read after
completing the questionnaires.
In the follow-up sample, SCAS-P scores at Time 1 and Time
2 (total and subscale) were compared using paired-samples
t-tests, and change over time in anxiety scores was correlated
with age and intellectual ability.
Corrections for multiple comparisons were not applied
due to low power caused by the relatively small sample size
in this study: an alpha value of 0.05 is applied throughout the
manuscript, whereby a p value greater than 0.05 indicates
a non-significant results. Furthermore, effect sizes are used
throughout the Results section to aid the interpretation of
(effect size for r are as follows −0.1 is small,
0.3 is medium, 0.5 is large according to Cohen 1988; effect
size for d are as follows − 0.2 small, 0.5 medium, 0.8 large,
again according to)
In the cross-sectional sample, SCAS-P scores were
correlated with chronological age. Next, the associations between
anxiety, social functioning, and executive functioning were
examined. Correlations between SCAS-P total scores and
(1) SRS-2 and (2) BRIEF scores were undertaken. Finally,
a backwards multiple regression was performed, using the
Enter method. SRS-2 total raw score and BRIEF T-scores
were included as the predictors, and SCAS-P total score as
the dependent variable.
Data for the follow-up sample are summarized in Table 1.
Mean age difference from Time 1 to Time 2 was 3.75 years
(SD = 0.43). At time point 1 mean RCPM score was 17.56
out of a maximum possible score of 36, and mean BPVS
raw score was 84.59 indicating an average verbal mental
age of 5 years 7 months. Neither RCPM nor BPVS scores
were significantly correlated to SCAS-P total score at Time
1 (BPVS: r(15) = 0.273, p = .289; RCPM: r(15) = 0.045,
p = .869) or Time 2 (BPVS: r(15) = 0.179, p = .492; RCPM:
r(15) = − 0.305, p = .251). However, medium effect sizes for
the correlations between Time 1 anxiety and BPVS score
and Time 2 anxiety and RCPM scores were found. This
suggests that greater anxiety may be associated with greater
verbal ability, but that poorer non-verbal ability is associated
with greater anxiety at follow-up. This appears to present
a conflicting picture in terms of the associations between
cognitive abilities and anxiety based on effect sizes and is
interpreted with caution.
The mean total SCAS-P scores at Time 1 and Time 2 for
the group were above the suggested cut-off for clinical
elevation of 24, increasing on average by 4.24 points over the
four year period. Paired-samples t-tests indicated that this
increase approached significance, with a small effect size,
however, there was significant individual variability (see
Table 1). Twelve individuals (71% of the follow-up sample)
increased in total anxiety from Time 1 to Time 2; five (29%)
decreased in total anxiety. Among those who became more
anxious, six individuals’ total scores increased by 9 points
or more, which is 1 SD based on a normative sample
et al. 2004)
. Among those who became less anxious, two
individuals’ total scores decreased by nine points or more
(see Fig. 1 for individual changes).
The change in anxiety (calculated as the difference
between total SCAS-P scores at Time 1 and Time 2) varied
widely across the sample, ranging from a decrease of 15
points to an increase of 25 points. This change was not
significantly correlated with chronological age, r(15) = − 0.076,
p = .771, BPVS scores, r(15) = − 0.110, p = .674, or RCPM
scores, r(15) = − 0.356, p = .177. Again, it should be noted
that the effect sizes for these correlations point towards a
possible association between a greater increase in anxiety
and lower non-verbal ability.
Changes in SCAS-P subscale scores for the group are
displayed in Fig. 2. Scores increased from Time 1 to Time 2
across all subscales, with the exception of Fears of Physical
Injury. Paired-samples t-tests (see Table 1) indicated that the
changes were not statistically significant for Panic Disorder,
Separation Anxiety, Physical Injury, OCD, and GAD. There
was a trend towards significance for the change in Social
Phobia. Effect sizes indicate there are likely to be clinically
relevant increases in Separation Anxiety, OCD, GAD, and
Social Phobia over time.
Profile of Anxiety in the Time 2 Sample
Data for the cross-sectional sample are summarized
in Table 2. Mean SCAS-P total score was 7.58 points
above the suggested cut-off for clinical elevation of 24.
indicating change over time at the individual level. Lines in red show
an increase and lines in blue show a decrease in anxiety. (Color figure
Nineteen individuals (73% of the sample) scored at or
above the cut-off, and were classified as “high-anxious”,
while seven (27%) scored below 24, and were
classified as “low-anxious”. Anxiety scores did not differ
between (M = 30.23, SD = 13.39) and females (M = 32.92,
SD = 14.25), t(24) = 0.496, p = .624, d = 0.195. The
correlation between total anxiety score and
chronological age was not significant, r(24) = 0.202, p = .161, nor
were the correlations between SCAS-P subscale scores
and chronological age (Panic Disorder: r(24) = 0.041,
p = .843; Separation Anxiety: r(24) = 0.084, p = .683;
Physical Injury: r(24) = 0.011, p = .957; Social Phobia:
r(24) = 0.370, p = .063; OCD: r(24) = 0.315, p = .117;
GAD: r(24) = 0.028, p = .892). There was a trend towards
significance for the correlation between Social Phobia
and age. Moreover, medium effect sizes for the
correlation between age and Social Phobia, as well as OCD and
total anxiety score suggest that overall anxiety along with
OCD and Social Phobia may increase with chronological
age in the sample.
How is Anxiety Related to Core Features of WS?
Anxiety and Social Functioning
On the SRS-2, five individuals (19% of the cross-sectional
sample) were reported to show normal levels of overall
functioning, 16 (62%) were reported to have mild-to-moderate
impairments, and five (19%) were reported to have severe
impairments. Chronological age was not significantly
correlated with SRS-2 total score, r(24) = − .022, p = .916,
suggesting that social abilities were not associated with
chronological age in WS. Pearson’s correlations were calculated
between SCAS-P total, and SRS-2 total. There was a
significant positive correlation found between SCAS-P total and
SRS-total with a medium effect size, r(24) = 0.353, p = .038,
indicating that greater atypicality of social function is
associated with higher anxiety.
Anxiety and Executive Functioning
Across all four BRIEF scales, the modal category of
function/dysfunction was clinically elevated; 35–50% of the
sample fell into this range, while 23–35% fell into the normal
range. Chronological age was not significantly associated
with T-scores on any of the BRIEF clinical scales (Inhibit:
r(24) = − 0.307, p = .127; self-monitor: r(24) = 0.005,
p = .980; shift: r(24) = 0.162, p = .429; emotion regulation:
r(24) = − 0.174, p = .395), However, interpretations based on
the effect sizes of these correlations indicate better Inhibition
was associated with increasing chronological age.
There was a significant positive correlation between
total anxiety score and T-scores for Inhibit, r(24) = 0.449,
p = .011, Shift, r(24) = 0.625, p < .001, and emotional
control, r(24) = 0.407, p = .019, with medium to large effect
sizes. The correlation between total anxiety and
Self-Monitor was not significant, r(24) = 0.124, p = .273.
Social and Executive Functioning
Exploratory Pearson’s correlations were performed to
investigate potential relationships between SRS-2 total
scores and each of the four BRIEF scales. Significant
positive correlations with medium to large effects sizes were
found between SRS-2 total and all four scales on the BRIEF,
Inhibit, r(24) = 0.611, p < .001, Self-Monitor, r(24) = 0.642,
p < .001, Shift, r(24) = 0.725, p < .001, and Emotional
Control, r(24) = 0.550, p = .002. suggesting strong associations
between social and executive functioning in WS. These
correlations held when only the Social Communicative Index
(SCI) from the SRS was used, therefore indicating that
the associations were not driven by repetitive behaviours
[SCI & Inhibit, r(24) = 0.613, p < .001, SCI & self-monitor,
r(24) = 0.644, p < .001, SCI & shift, r(24) = 0.689, p < .001,
and SCI & emotional control, r(24) = 0.497, p = .005].
Predicting Anxiety from Social and Executive Functioning
In the regression analysis, the following variables were
included as predictors, as they were significantly correlated
with the dependent variable (SCAS-P total): SRS-2 total, and
BRIEF- Inhibit, Shift, and Emotional Control (see Table 3).
The initial model generated (adjusted R2 = 0.311) was a
significant predictor of overall anxiety score, F(4,21) = 3.823,
p = .017. Once the remaining variables were controlled for,
SRS-2 total (p = .323), Inhibit (p = .649), and Emotional
Control (p = .793) were not significantly related to total
SCAS-P score (partial correlations: rs < 0.100, ps > 0.323).
In other words, the unique variance between each of these
predictors and total anxiety score was non-significant.
However, Shift was found to be a significant predictor of
SCASP total score, β = .702, t(21) = 2.595, p = .017. The positive
Beta weighting for this coefficient indicated that those with
greater problems in this domain had higher anxiety levels
This study aimed to investigate changes in anxiety in WS
over a 4 year period, and to explore how anxiety was
associated with other core features of the disorder, namely social
and executive functioning. As predicted, and in support of
the existing literature
(e.g. Leyfer et al. 2006;
WoodruffBorden et al. 2010)
, over 70% of the current cross-sectional
sample scored above the specified cut-off for clinically
elevated anxiety levels. This was higher than the 42% reported
by Riby et al. (2014), and the 38% reported by McGrath
et al. (2016), although a recent meta-review by
et al. (2016
) show that prevalence rates for anxiety disorder
in WS have been reported to be as high as 82.2%.
Therefore, our results further emphasise that anxiety is a
significant issue for many individuals with WS. Additionally, our
results indicated that most individuals became more anxious
over time. The overall change in anxiety was not significant,
although there was a trend towards significance, with a small
to medium effect size. Effect sizes also indicated increases in
several aspects of anxiety, such as separation anxiety, OCD,
GAD, and SP. From this we can provide tentative support
for the idea that anxiety is a chronic issue that worsens over
time, but future studies with larger samples are warranted to
more fully understand the developmental trajectory
(Woodruff-Borden et al. 2010)
. Additionally, there was
considerable individual variability in how anxiety changed over time
in the follow-up sample, and a small proportion (one-third)
of the sample became less anxious over time. This highlights
a need to examine systematically potential risk and
protective factors driving these longitudinal changes.
One aim within this study was to explore the role of
age in anxiety, as reports in the literature are mixed as to
whether anxiety increases with age. We did not find a clear
correlation with age, and therefore propose two alternative
explanations. On the one hand, given the relatively small
sample size, the lack of significance may have been due to
insufficient power. We note that the effect sizes for the
correlations between age and the change in anxiety over time/
anxiety in the cross-sectional sample at time 2 were both
small (≤ 0.2). However, the effect sizes for the association
between age and some of the anxiety subscale measures
were medium to large, highlighting that there may be
agerelated changes in aspects of anxiety such as social phobia
and OCD. Alternatively, sample differences could underlie
the conflict with existing reports of age-related increases in
(e.g. Leyfer et al. 2006)
. Leyfer et al. (2006) only
included participants up to age 16, and therefore could not
extend their findings to adults with WS. In contrast, the
current sample had a much wider age-range. Indeed, lack of
association between anxiety and age has also been reported
in similarly composed samples
(Riby et al. 2014)
, and it is
possible that a quadratic relationship exists between
anxiety and chronological age, such that anxiety increases from
childhood to adolescence, and subsequently decreases from
adolescence into adulthood. Future studies with larger
samples could bring clarity to this issue by comparing the
presentation of anxiety in WS between different age groups, and
by paying particular interest to aspects of anxiety such as
social phobia and OCD.
Our results showed that higher anxiety was associated with
greater impairments in overall social functioning, in line
with previous reports
(Kirk et al. 2013; Riby et al. 2014)
It has been suggested that difficulties in social functioning
in ASD contribute towards anxiety via increasing
difficulties in navigating social situations and subsequent social
isolation (White et al. 2009). This may also be the case in
WS, particularly if we take into account the characteristic
strong desire for social interaction
(Ng et al. 2014a)
these results, incorporating social-skills training into the
design of anxiety interventions in WS, as has been done
(e.g. Wood et al. 2009)
, is worth consideration. As
these findings are correlational, further prospective work is
required to delineate the directions and trajectories of these
Anxiety and Executive Functioning
Corroborating and extending the existing literature
Woodruff-Borden et al. 2010)
, greater impairments in
EFs—specifically inhibit, shift, and emotional control—
were associated with higher levels of anxiety. In light of
these findings, it is important to consider the role these
specific functions play. For example, poor inhibitory control
is postulated to underlie anxiety symptoms such as
(Green et al. 2012)
, while poor emotional
control may underlie emotional outbursts during distressing
(Ng et al. 2014b)
. If so, then dysregulation across
these domains might explain increased anxious
symptomatology. Future studies would be required to substantiate
these findings and prospectively study the direction of these
associations. Nonetheless, these results raise the possibility
of targeting anxiety in WS with a range of EF-based
interventions, which have received growing empirical support
for improving cognitive, social, and emotional outcomes in
typically developing children (see Diamond and Lee 2011).
Predicting Anxiety from Social and Executive
A unique aspect of this study was the integration of social
and executive functioning in a model predicting anxiety in
WS. Regression analysis revealed that when controlling for
the other variables, Shift alone remained a significant
predictor, reflecting a strong independent relationship between
anxiety and cognitive flexibility. A crucial next step is to
consider the pathways by which this ability relates to
anxiety. According to attentional control (AC) theory
(Derryberry and Reed 2002)
, excessive anxiety upsets the balance
between stimulus-driven and goal-driven attention
processes, causing over-responsiveness to, and biased
processing of threatening stimuli. More recently, researchers have
focused on subtypes of AC mechanisms, demonstrating that
the ability to shift rather than focus attention is related to
biased processing of threatening stimuli in anxiety
et al. 2016)
It is possible that in WS early difficulties in
attentionshifting underpin a cycle of hyperawareness to and
fixation on threat, resulting in elevated anxiety
(McGrath et al.
. However, an alternative account has been raised by
Kirk et al. (2013), who used the SCAS and a facial
expression task in an eye-tracking study exploring the relationship
between anxiety and social attention in WS. They found that
anxious individuals with WS were initially over-attentive to,
but subsequently avoided threatening stimuli (angry faces)
by allocating attention elsewhere, suggesting a dual process
of vigilance and avoidance
(see Mogg and Bradley 1998)
These differing accounts warrant further investigations to
shed light on the precise mechanisms by which attentional
and executive processes influence anxiety in WS. These
efforts may guide the application of existing attention-based
treatments for anxiety, such as Attention Bias Modification
(ABM; see Lowther and Newman 2014)
, a computerized
programme which involves training one’s attention to avoid
One particularly intriguing finding casts new light on the
relationship between anxiety and social functioning in WS.
The regression model revealed that once shared variance
in EF abilities were controlled for, the positive association
between anxiety and social functioning no longer held.
This raises the possibility of a mediating effect of EF in
the relationship between anxiety and social functioning in
WS. Turning to the literature on typical development, early
executive dysfunction (poor inhibitory control, high
impulsivity, and poor adaptive and attentional flexibility) has been
found to predict poor social competence and externalizing
and internalizing problems later in life
(see Eisenberg et al.
. Furthermore, associations between social behaviours
and EF in WS have been investigated elsewhere. Most
notably, evidence that that impaired inhibitory control underlies
inappropriate social approach behaviours
(Little et al. 2013)
supports the frontal lobe hypothesis
(Porter et al. 2007)
Indeed, exploratory correlations between the SRS-2
and the BRIEF revealed significant, positive relationships
across all four scales, further supporting the notion that EF
underlies both social and emotional outcomes in WS. We
stress that these findings are only preliminary, and must
therefore be interpreted cautiously and substantiated with
further systematic research. Nonetheless, they provide a
compelling rationale for future efforts to prospectively study
the development of EFs in WS, with a focus on exploring
potential cascading effects on a range of psychopathological
outcomes. It would be particularly beneficial if social and
emotional vulnerabilities could be identified and targeted
for intervention, based on early indicators such as executive
Considerations and Future Research
Several considerations should be addressed in future
research. One challenge to working with individuals with
WS is the rarity of the disorder. The relatively small sample
size in the current study may have limited power to detect
statistically significant effects. One way to overcome this in
future work would be to engage in collaborative multisite
studies. Larger scale work on this issue would allow analysis
to probe the potential mediating effects of executive
functioning on the association between social functioning and
anxiety, and findings where effects sizes indicated further
consideration on a larger scale is necessary (association with
non-verbal ability and anxiety). Another issue pertains to
our reliance on measures of anxiety designed for
individuals without neurodevelopmental disorders (e.g. SCAS-P).
Attempts to capture more sensitively the anxiety profile in
WS could utilize new measures designed for individuals with
ASDs, for whom anxiety is similarly characterized by issues
with sensory hypersensitivity and worry in anticipation of
(e.g. Rodgers et al. 2016)
. Ideally, parallel
scales designed for children with developmental disorders
and adults would facilitate the meaningful measurement of
anxiety across the wide age-range in this sample. However,
such measures have yet to be developed and validated
empirically. Therefore, in recognizing this limitation, we highlight
the need to develop targeted assessment measures.
Additionally, reliance on parental insights on
questionnaire measures may lead to retrospective or subjective biases
(see Dykens 2003)
, while the use of a single respondent
may result in shared variance across the three measures.
One way to address these issues in future would be to
collect data from multiple informants
(e.g. Klein-Tasman et al.
, or use self-report measures
(e.g. Freeman et al. 2010)
However, this can be especially challenging for younger
individuals and those with lower intellectual capabilities.
Moreover, parent-report measures are often used in
clinical assessments of atypically developing populations, and
we believe that the parents in the current study were able
to adequately report on their children’s behaviours and
functioning. Finally, it is important to take into account the
potential for self-selection on studies of anxiety: for
example, parents of particularly anxious individuals, or those with
greater concerns about their child’s anxiety problems, may
have been more likely to respond. However, given the
considerable individual variation in overall anxiety scores, we
believe the current sample provides a sufficiently balanced
portrayal of the WS anxiety profile.
In conclusion, the current study highlights that
heightened anxiety persists for many individuals with WS over
time, and that executive functions may play an important
role in this. We have proposed a top-down influence of
executive functions on both anxiety and social functioning, and
recommend future prospective investigations to study the
downstream effects of early neuropsychological functioning
in WS. Knowledge about the presentation and development
of anxiety in WS, as well as dynamic associations with
cognition and behaviour are imperative for the development of
appropriate prevention and intervention strategies.
Acknowledgments The authors would like to thanks the families
who participated in the research, and the support of the Williams
syndrome Association of Ireland and the Williams syndrome Foundation
Author Contributions ENC led the data collection, analysis,
interpretation of the data and drafting of the manuscript; MH and DR
conceived of the study, participated in its design, coordination,
interpretation of the data and drafted the manuscript; AK participated in the
data collection and analysis; All authors read and approved the final
Open Access This article is distributed under the terms of the
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