An investigation of a novel broad autism phenotype: increased facial masculinity among parents of children on the autism spectrum.

The broad autism phenotype commonly refers to sub-clinical levels of autistic-like behaviour and cognition presented in biological relatives of autistic people. In a recent study, we reported findings suggesting that the broad autism phenotype may also be expressed in facial morphology, specifically increased facial masculinity. Increased facial masculinity has been reported among autistic children, as well as their non-autistic siblings. The present study builds on our previous findings by investigating the presence of increased facial masculinity among non-autistic parents of autistic children. Using a previously established method, a 'facial masculinity score' and several facial distances were calculated for each three-dimensional facial image of 192 parents of autistic children (58 males, 134 females) and 163 age-matched parents of non-autistic children (50 males, 113 females). While controlling for facial area and age, significantly higher masculinity scores and larger (more masculine) facial distances were observed in parents of autistic children relative to the comparison group, with effect sizes ranging from small to medium (0.16 ≤ d ≤ .41), regardless of sex. These findings add to an accumulating evidence base that the broad autism phenotype is expressed in physical characteristics and suggest that both maternal and paternal pathways are implicated in masculinized facial morphology.

A longitudinal examination of perinatal testosterone, estradiol and vitamin D as predictors of handedness outcomes in childhood and adolescence.

The developmental origins of handedness remain elusive, though very early emergence suggests individual differences manifesting in utero could play an important role. Prenatal testosterone and Vitamin D exposure are considered, yet findings and interpretations remain equivocal. We examined n = 767 offspring from a population-based pregnancy cohort (The Raine Study) for whom early biological data and childhood/adolescent handedness data were available. We tested whether 18-week maternal circulatory Vitamin D (25[OH]D), and testosterone and estradiol from umbilical cord blood sampled at birth predicted variance in direction of hand preference (right/left), along with right- and left-hand speed, and the strength and direction of relative hand skill as measured by a finger-tapping task completed at 10 (Y10) and/or 16 (Y16) years. Although higher concentrations of Vitamin D predicted more leftward and less lateralized (regardless of direction) relative hand skill profiles, taken as a whole, statistically significant findings typically did not replicate across time-point (Y10/Y16) or sex (male/female) and were rarely detected across different (bivariate/multivariate) levels of analysis. Considering the number of statistical tests and generally inconsistent findings, our results suggest that perinatal testosterone and estradiol contribute minimally, if at all, to subsequent variance in handedness. Vitamin D, however, may be of interest in future studies.

Delayed cortical processing of auditory stimuli in children with autism spectrum disorder: A meta-analysis of electrophysiological studies.

Several researchers have hypothesised that individuals with Autism Spectrum Disorder (ASD) show encoding delays in their obligatory event-related potentials (ERPs)/ event-related fields (ERFs) for low-level auditory information compared to neurotypical (NT) samples. However, empirical research has yielded varied findings, such as low-level auditory processing in ASD samples being unimpaired, superior, or impaired compared to NT samples. Diverse outcomes have also been reported for studies investigating ASD-NT differences in functional lateralisation of delays. The lack of consistency across studies has prevented a comprehensive understanding of the overall effects in the autistic population. Therefore, this meta-analysis compared long-latency ERPs and ERFs produced by autistic and NT individuals to non-linguistic auditory stimuli to test, firstly, the robustness of auditory processing differences and, secondly, whether these differences are observed in one or both hemispheres. Nine articles meeting the inclusion criteria were included in the meta-analysis. Meta-analytic results indicated that autistic individuals demonstrate bilaterally delayed P1/ M50 peaks and lateralised delays in the right but not left hemisphere N1/ M100 peak. These results further inform our understanding of auditory processing and lateralisation across the autism spectrum.

Deconstructing the repetitive behaviour phenotype in autism spectrum disorder through a large population-based analysis.

OBJECTIVE: Restricted and repetitive pattern of behaviours and interests (RRB) are a cardinal feature of autism spectrum disorder (ASD), but there remains uncertainty about how these diverse behaviours vary according to individual characteristics. This study provided the largest exploration to date of the relationship between Repetitive Motor Behaviours, Rigidity/Insistence on Sameness and Circumscribed Interests with other individual characteristics in newly diagnosed individuals with ASD. METHOD: Participants (N = 3,647; 17.7% females; Mage = 6.6 years [SD = 4.7]) were part of the Western Australian (WA) Register for ASD, an independent, prospective collection of demographic and diagnostic data of newly diagnosed cases of ASD in WA. Diagnosticians rated each of the DSM-IV-TR criteria on a 4-point Likert severity scale, and here we focused on the Repetitive Motor Behaviours, Insistence on Sameness and Circumscribed Interests symptoms. RESULTS: The associations between RRB domains, indexed by Kendall's Tau, were weak, ranging from non-significant for both Circumscribed Interests and Repetitive Motor Behaviours to significant (.20) for Insistence on Sameness and Repetitive Motor Behaviours. Older age at diagnosis was significantly associated with lower Circumscribed Interests and significantly associated with higher Insistence on Sameness and Repetitive Motor Behaviours. Male sex was significantly associated with higher Repetitive Motor Behaviours but not Insistence on Sameness or Circumscribed Interests. CONCLUSIONS: The pattern of associations identified in this study provides suggestive evidence for the distinctiveness of Repetitive Motor Behaviours, Insistence on Sameness and Circumscribed Interests, highlighting the potential utility of RRB domains for stratifying the larger ASD population into smaller, more phenotypically homogeneous subgroups that can help to facilitate efforts to understand diverse ASD aetiology and inform design of future interventions.

Prenatal testosterone exposure is related to sexually dimorphic facial morphology in adulthood.

Prenatal testosterone may have a powerful masculinizing effect on postnatal physical characteristics. However, no study has directly tested this hypothesis. Here, we report a 20-year follow-up study that measured testosterone concentrations from the umbilical cord blood of 97 male and 86 female newborns, and procured three-dimensional facial images on these participants in adulthood (range: 21-24 years). Twenty-three Euclidean and geodesic distances were measured from the facial images and an algorithm identified a set of six distances that most effectively distinguished adult males from females. From these distances, a 'gender score' was calculated for each face, indicating the degree of masculinity or femininity. Higher cord testosterone levels were associated with masculinized facial features when males and females were analysed together (n = 183; r = -0.59), as well as when males (n = 86; r = -0.55) and females (n = 97; r = -0.48) were examined separately (p-values < 0.001). The relationships remained significant and substantial after adjusting for potentially confounding variables. Adult circulating testosterone concentrations were available for males but showed no statistically significant relationship with gendered facial morphology (n = 85, r = 0.01, p = 0.93). This study provides the first direct evidence of a link between prenatal testosterone exposure and human facial structure.

Hallucinations and inhibitory functioning in healthy young adults with high and low levels of hypomanic personality traits.

INTRODUCTION: Hallucinations in schizophrenia and hallucination proneness in healthy young adults are associated with a common cognitive mechanism, namely impaired inhibitory control. Hallucinatory-like experiences also seem related to hypomanic symptoms in non-clinical participants; however, the mechanisms involved are unknown. We sought to examine self-reported hallucinatory/anomalous perceptual experiences in students selected for high versus low levels of hypomanic personality traits, and whether hypomania is characterised by deficient inhibitory control. METHOD: Undergraduate students with either high (n = 26) or low (n = 28) scores on the Hypomanic Personality Scale-Revised (HPS-20) were compared on: (1) the Launay Slade Hallucination Scale-Revised (LSHS-R), a measure of hallucination proneness, (2) the Cardiff Anomalous Perceptions Scale (CAPS) and (3) the Inhibition of Currently Irrelevant Memories (ICIM) task, an index of intentional inhibition. RESULTS: The high HPS group had higher total scores, as well as higher frequency (on CAPS only), intrusiveness and distress (CAPS) scores compared to the low HPS group. They also produced significantly more false alarms on the second run of the ICIM task than the low hypomania traits group. CONCLUSIONS: Frequent, intrusive and distressing perceptual anomalies and proneness to hallucinations tend to occur in healthy individuals with hypomanic personality traits and may be associated with transient difficulties with inhibitory control. Inhibitory control may be a cognitive marker of vulnerability to hallucinations across diagnostic boundaries.

Evidence for shared deficits in identifying emotions from faces and from voices in autism spectrum disorders and specific language impairment.

BACKGROUND: While autism spectrum disorder (ASD) and specific language impairment (SLI) have traditionally been conceptualized as distinct disorders, recent findings indicate that the boundaries between these two conditions are not clear-cut. While considerable research has investigated overlap in the linguistic characteristics of ASD and SLI, relatively less research has explored possible overlap in the socio-cognitive domain, particularly in terms of the emotion recognition abilities of these two groups of children. AIMS: To investigate facial and vocal emotion recognition in children with ASD, children with SLI and typically developing (TD) children. To do so, the ASD group was subdivided into those with 'normal' (ALN) and those with 'impaired' (ALI) language to explore the extent to which language ability influenced performance on the emotion recognition task. METHODS & PROCEDURES: Twenty-nine children with ASD (17 ALN and 12 ALI), 18 children with SLI and 66 TD children completed visual and auditory versions of an emotion recognition task. For the visual version of the task, the participants saw photographs of people expressing one of six emotions (happy, sad, scared, angry, surprised, disgusted) on the whole face. For the auditory modality, the participants heard a neutral sentence that conveyed one of the six emotional expressions in the tone of the voice. In both conditions, the children were required to indicate how the person they could see/hear was feeling by selecting a cartoon face that was presented on the computer screen. OUTCOMES & RESULTS: The results showed that all clinical groups were less accurate than the TD children when identifying emotions on the face and in the voice. While the ALN children were less accurate than the TD children only when identifying expressions that require inferring another's mental state (surprise, disgust) emotional expressions, the ALI and the SLI children were less accurate than the TD children when identifying the basic (happy, sad, scared, angry) as well as the inferred emotions. CONCLUSIONS & IMPLICATIONS: The results indicate that children with ALI and children with SLI share emotion recognition deficits, which are likely to be driven by the poor language abilities of these two groups.

Voice identity discrimination and hallucination-proneness in healthy young adults: a further challenge to the continuum model of psychosis?

INTRODUCTION: Auditory hallucinations occur in schizophrenia and also in the general population. However, evidence points to differences in the nature and the mechanisms of clinical and non-clinical hallucinations, challenging the dominant assumption that they represent the same phenomenon. The current study extended this evidence by examining voice identity perception in hallucination-prone individuals. In schizophrenia, deficiencies discriminating between real (external) voices have been linked to basic acoustic cues, but voice discrimination has not yet been investigated in non-clinical hallucinations. METHODS: Using a task identical to that employed in patients, multidimensional scaling of voice dissimilarity judgements was used to examine how healthy individuals differing in hallucination-proneness (30 high and 30 low hallucination-prone individuals) distinguish pairs of unfamiliar voices. The resulting dimensions were interpreted with reference to acoustic measures relevant to voice identity. RESULTS: A two-dimensional "voice space", defined by fundamental frequency (F0) and formant dispersion (Df), was derived for high and low hallucination-prone groups. There were no significant differences in speaker discrimination for high versus low hallucination-prone individuals on the basis of either F0 or Df. CONCLUSIONS: These findings suggest voice identity perception is not impaired in healthy individuals predisposed to hallucinations, adding a further challenge to the continuum model of psychotic symptoms.

Auditory context-dependent distraction by unexpected visual stimuli.

Research findings indicate that when a task-irrelevant stimulus feature deviates from an otherwise predictable pattern, participants performing a categorization task exhibit slower responses (deviance distraction). This deviance distraction effect reflects the violation of the sensory predictions generated by the cognitive system. In this study, we sought to examine for the first time whether these predictions can be incidentally modulated by the auditory environment. Participants categorized the duration (short vs long) of a colored shape (red square or blue circle) while instructed to disregard the stimulus' visual features and the sound played in the background (two distinct chords played by different instruments). While the two visual stimuli shapes were equiprobable across the task, one was highly likely (p=.882) and the other rare (p=.118) in one auditory context and vice versa in the other context. Our results showed that participants were significantly slower in the duration judgement task whenever the stimulus was unexpected within a given auditory context (context-dependent distraction), and that the reset of their sensory predictions was completed upon the trial following a change of context. We conclude that object features and environmental context are processed in relation to each other and that sensory predictions are produced in relation to the environmental context, evidencing the first demonstration of auditory context-dependent modulation of attention.

Autistic traits specific to communication ability are associated with performance on a Mooney face detection task.

Difficulties in global face processing have been associated with autism. However, autism is heterogenous, and it is not known which dimensions of autistic traits are implicated in face-processing difficulties. To address this gap in knowledge, we conducted two experiments to examine how identification of Mooney face stimuli (stylized, black-and-white images of faces without details) related to the six subscales of the Comprehensive Autistic Trait Inventory in young adults. In Experiment 1, regression analyses indicated that participants with poorer communication skills had lower task sensitivity when discriminating between face-present and face-absent images, whilst other autistic traits had no unique predictive value. Experiment 2 replicated these findings and additionally showed that autistic traits were linked to a reduced face inversion effect. Taken together, these results indicate autistic traits, especially communication difficulties, are associated with reduced configural processing of face stimuli. It follows that both reduced sensitivity for identifying upright faces amongst similar-looking distractors and reduced susceptibility to face inversion effects may be linked to relatively decreased reliance on configural processing of faces in autism. This study also reinforces the need to consider the different facets of autism independently.

Visuospatial cueing differences as a function of autistic traits.

Atypical orienting of visuospatial attention in autistic individuals or individuals with a high level of autistic-like traits (ALTs) has been well documented and viewed as a core feature underlying the development of autism. However, there has been limited testing of three alternative theoretical positions advanced to explain atypical orienting - difficulty in disengagement, cue indifference, and delay in orienting. Moreover, research commonly has not separated facilitation (reaction time difference between neutral and valid cues) and cost effects (reaction time difference between invalid and neutral cues) in orienting tasks. We addressed these limitations in two experiments that compared groups selected for Low- and High-ALT levels on exogenous and endogenous versions of the Posner cueing paradigm. Experiment 1 showed that High-ALT participants exhibited a significantly reduced cost effect compared to Low-ALT participants in the endogenous cueing task, although the overall orienting effect remained small. In Experiment 2, we increased task difficulty of the endogenous task to augment cueing effects. Results were comparable to Experiment 1 regarding the finding of a reduced cost effect for High-ALT participants on the endogenous cueing task and additionally demonstrated a reduced facilitation effect in High-ALT participants on the same task. No ALT group differences were observed on an exogenous cueing task included in Experiment 2. These findings suggest atypical orienting in High-ALT individuals may be attributable to general cue indifference, which implicates differences in top-down attentional processes between Low- and High-ALT individuals. We discuss how indifference to endogenous cues may contribute to social cognitive differences in autism.

Investigating Parental Observations of Early Autism Development in Simplex and Multiplex Families.

Past research has highlighted the importance of early identification of developmental differences to improve targeted access to early interventions or supports. As such, it is of particular importance in the context of children at elevated likelihood of autism (such as where an older sibling has a diagnosis of autism), to better understand when and which early concerns are important as predictors of which children will benefit from pre-diagnostic supports. This study explored the number and frequency of retrospective parent reported concerns within the first year of life for children diagnosed with autism, both those who had an older sibling diagnosed with autism and those who did not, as well as for undiagnosed siblings. We found that at both 0-6 and 7-12 months, the only factor related to the presence or absence of early parent reported concerns was child diagnostic status, with the presence of reported early concerns more likely for children with a diagnosis of autism. These findings suggest that for children at elevated likelihood of autism, parents' concerns are driven primarily by developmental differences, with child's birth order and sibling diagnostic status not impacting on parent early concerns.

The Psychometric Assessment of Empathy: Development and Validation of the Perth Empathy Scale.

Empathy, the ability to infer and share others' affective states, plays a vital role in social interactions. However, no existing scale comprehensively assesses empathy's cognitive and affective components across positive and negative emotional valence domains. This article explores the latent structure of the empathy construct and attempts to remedy past measurement limitations by developing and validating a new 20-item self-report measure, the Perth Empathy Scale (PES). In Study 1 (N = 316), factor analyses revealed a coherent empathy construct comprised of cognitive and valence-specific affective components. Study 2 (N = 331) replicated this factor structure, showed measurement invariance between males and females, and highlighted the importance of assessing negative and positive emotions in empathy. The PES showed convergent and discriminant validity from comparisons with alexithymia and other empathy measures. Overall, this article empirically establishes a conceptually clear structure of the multidimensional empathy construct, which the PES reliably and validly measures.

The first six months of life: A systematic review of early markers associated with later autism.

There is now good evidence that behavioural signs of autism spectrum conditions (autism) emerge over the first two years of life. Identifying clear developmental differences early in life may facilitate earlier identification and intervention that can promote longer-term quality of life. Here we present a systematic review of studies investigating behavioural markers of later autism diagnosis or symptomology taken at 0-6 months. The following databases were searched for articles published between 01/01/2000 and 15/03/2022: Embase, Medline, Scopus, PubMed, PsycINFO, CINAHL, Web of Science and Proquest. Twenty-five studies met inclusion criteria: assessment of behaviour at 0-6 months and later assessment of autism symptomology or diagnosis. Studies examined behaviours of attention, early social and communication behaviours, and motor behaviours, as well as composite measures. Findings indicated some evidence of measures of general attention, attention to social stimuli, and motor behaviours associated with later autism diagnosis or symptomology. Findings were inconsistent regarding social and communication behaviours, with a lack of repeated or validated measures limiting drawing firm conclusions. We discuss implications of the findings and suggest recommendations for future research.

A review of behavioral evidence for hemispheric asymmetry of visuospatial attention in autism.

Most individuals show a small bias towards visual stimuli presented in their left visual field (LVF) that reflects right-hemispheric specialization of visuospatial functions. Moreover, this bias is altered by some neurodevelopmental disorders, suggesting they may be linked to changes in hemispheric asymmetry. To examine whether autism potentially alters hemispheric asymmetry, we conducted a systematic search of scientific databases to review existing literature on the link between autism and alterations in visuospatial bias. This search identified 13 publications that had explored this issue using a wide range of experimental designs and stimuli. Evidence of reduced LVF bias associated with autism was most consistent for studies examining attentional bias or preference measured using tasks such as line bisection. Findings for studies examining attentional performance (e.g., reaction time) were more equivocal. Further investigation is called for, and we make several recommendations for how this avenue of research can be extended.

Parent-child interaction and developmental outcomes in children with typical and elevated likelihood of autism.

BACKGROUND: Early parent-child interactions have a critical impact on the developmental outcomes of the child. It has been reported that infants with a family history of autism and their parents may engage in different patterns of behaviours during interaction compared to those without a family history of autism. This study investigated the association of parent-child interactions with child developmental outcomes of those with typical and elevated likelihood of autism. METHOD: This longitudinal study investigated the relationship between global attributes of parent-child interaction and the developmental outcomes of infant siblings with elevated likelihood (EL: n = 29) or typical likelihood (TL: n = 39) of developing autism. Parent-child interactions were recorded during a session of free-play when the infants were six months of age. Developmental assessments were carried out when the children were 12 and 24 months of age. RESULTS: The intensity of mutuality was significantly higher in the TL group than in the EL group, and developmental outcomes were poorer in the EL group when compared to the TL group. Positive associations between parent-child interaction scores at six months and developmental outcomes at 12 months were observed only in the TL group. However, in the EL group, higher levels of infant positive affect and attentiveness paid to the caregiver is associated with lower autism symptoms. Due to the sample size and design of the study, the findings must be viewed as indicative. CONCLUSION: This preliminary investigation demonstrated differences in the association between parent-child interaction quality and developmental outcomes for children with typical and elevated likelihood for autism. Future studies should combine micro-analytic and macro-analytic approaches to parent-child interaction to further examine the nature of this relationship.

Assessing Restricted and Repetitive Behaviours in Online-Sampled Autistic and Non-autistic Individuals: Factor Structure of the Repetitive Behaviours Questionnaire for Adults (RBQ-2A).

The Repetitive Behaviours Questionnaire for Adults (RBQ-2A) measures two factors of restricted and repetitive behaviours (RRBs) associated with autism. However, the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) provides four criteria for RRBs: repetitive motor behaviours, insistence on sameness, restricted interests, and interest in sensory aspects of the environment (or atypical sensitivity). The current paper aimed to examine whether the RBQ-2A is a psychometrically sound measure of these four factors. Study 1 had university students (N = 368) complete the RBQ-2A and other related measures online and revealed that the RBQ-2A can assess the factors highlighted in the DSM-5 and that these four factors comprise a general RRB construct. Study 2 had individuals disclosing a diagnosis of autism (N = 283) complete the RBQ-2A and other related measures online and supported that this four-factor structure provided good psychometric properties. While the current paper provides findings for an online autistic population, further research is needed to generalize these findings to autistic individuals less likely to partake in online studies (e.g., those with intellectual or language disabilities). Overall, the results suggest that the RBQ-2A reliably and validly assesses RRBs.

Parent-Child Interactions May Help to Explain Relations Between Parent Characteristics and Clinically Observed Child Autistic Behaviours.

The importance of supporting parent-child interactions has been noted in the context of prodromal autism, but little consideration has been given to the possible contributing role of parental characteristics, such as psychological distress. This cross-sectional study tested models in which parent-child interaction variables mediated relations between parent characteristics and child autistic behaviour in a sample of families whose infant demonstrated early signs of autism (N = 103). The findings suggest that associations between parent characteristics (psychological distress; aloofness) and child autistic behaviours may be mediated by the child's inattentiveness or negative affect during interactions. These findings have important implications in developing and implementing interventions in infancy which target the synchrony of parent-child interaction with the goal to support children's social communication development.

Sex-specific associations between umbilical cord blood testosterone levels and language delay in early childhood.

BACKGROUND: Preliminary evidence suggests that prenatal testosterone exposure may be associated with language delay. However, no study has examined a large sample of children at multiple time-points. METHODS: Umbilical cord blood samples were obtained at 861 births and analysed for bioavailable testosterone (BioT) concentrations. When participating offspring were 1, 2 and 3 years of age, parents of 767 children (males = 395; females = 372) completed the Infant Monitoring Questionnaire (IMQ), which measures Communication, Gross Motor, Fine Motor, Adaptive and Personal-Social development. Cut-off scores are available for each scale at each age to identify children with 'clinically significant' developmental delays. Chi-square analyses and generalized estimating equations examined longitudinal associations between sex-specific quartiles of BioT concentrations and the rate of developmental delay. RESULTS: Significantly more males than females had language delay (Communication scale) at age 1, 2 and 3 years (p-values ≤. 01). Males were also more likely to be classified as delayed on the Fine-Motor (p = .04) and Personal-Social (p < .01) scales at age 3 years. Chi-square analyses found a significant difference between BioT quartiles in the rate of language delay (but not Fine-Motor and Personal-Social delay) for males (age 3) and females (age 1 and 3). Generalized estimating equations, incorporating a range of sociodemographic and obstetric variables, found that males in the highest BioT quartile were at increased risk for a clinically significant language delay during the first 3 years of life, with an odds ratio (OR) of 2.47 (95% CI: 1.12, 5.47). By contrast, increasing levels of BioT reduced the risk of language delay among females (Quartile 2: OR = 0.23, 95% CI: 0.09, 0.59; Quartile 4: 0.46, 95% CI: 0.21, 0.99). CONCLUSION: These data suggest that high prenatal testosterone levels are a risk factor for language delay in males, but may be a protective factor for females.

Language, cognitive flexibility, and explicit false belief understanding: longitudinal analysis in typical development and specific language impairment.

The hypothesis that language plays a role in theory-of-mind (ToM) development is supported by a number of lines of evidence (e.g., H. Lohmann & M. Tomasello, 2003). The current study sought to further investigate the relations between maternal language input, memory for false sentential complements, cognitive flexibility, and the development of explicit false belief understanding in 91 English-speaking typically developing children (M age = 61.3 months) and 30 children with specific language impairment (M age = 63.0 months). Concurrent and longitudinal findings converge in supporting a model in which maternal language input predicts the child's memory for false complements, which predicts cognitive flexibility, which in turn predicts explicit false belief understanding.