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Background & aims: Due to the complexity of early diagnostic decision making, we examined the predictive value of an early diagnostic classification and early abilities on later best estimate diagnosis for 22 clinically referred children with language difficulties. Methods and procedures: Four years after initial evaluation (Time 1), the clinical files of these children were reviewed. A best-estimate (BE) diagnosis of language disorder (LD), intellectual disability (ID), or autism spectrum disorder (ASD) was established, with ASD being most common. Outcomes and results: Early clinical classifications were relatively unstable or difficult to establish at a young age. The magnitude of children's cognitive and receptive language delay was a significant predictor of a later BE diagnosis of ID and LD respectively. A BE diagnosis of ASD, by contrast, could not be predicted from children's early social communication problems nor the presence of restricted and repetitive behaviors and interests. Conclusions: Taken together, the results of this study suggest that language difficulties can be an early marker of a neurodevelopmental disorder which is often not identified at the age of first referral. Implications: Eligibility for treatment should, therefore, be based on biopsychosocial case formulation rather than DSM or ICD diagnostic classification. What this paper adds?: In this study a dimensional approach was used to characterize the abilities of young children referred with mild to profound receptive and/or expressive language difficulties. Later on, a categorical approach was adopted to establish best estimate diagnoses. Our clinical, broadly defined sample reflects the heterogeneous intake of young children referred for diagnostic assessment. Other studies on diagnostic stability often only focus on one diagnostic category (and are explicitly excluding children with specific other diagnoses), not taking into account the difficulties of early differential diagnostic decision making and stability across different categories over time. Investigations of differential diagnosis within a clinical group, instead of only differentiating children with a specific diagnosis from typically developing children, may be more informative for clinicians.

Recognizing Mendelian causes is crucial in molecular diagnostics and counseling for patients with autism spectrum disorder (ASD). We explored facial dysmorphism and facial asymmetry in relation to genetic causes in ASD patients and studied the potential of objective facial phenotyping in discriminating between Mendelian and multifactorial ASD. In a cohort of 152 ASD patients, 3D facial images were used to calculate three metrics: a computational dysmorphism score, a computational asymmetry score, and an expert dysmorphism score. High scores for each of the three metrics were associated with Mendelian causes of ASD. The computational dysmorphism score showed a significant correlation with the average expert dysmorphism score. However, in some patients, different dysmorphism aspects were captured making the metrics potentially complementary. The computational dysmorphism and asymmetry scores both enhanced the individual expert dysmorphism scores in differentiating Mendelian from non‐Mendelian cases. Furthermore, the computational asymmetry score enhanced the average expert opinion in predicting a Mendelian cause. By design, our study does not allow to draw conclusions on the actual point‐of‐care use of 3D facial analysis. Nevertheless, 3D morphometric analysis is promising for developing clinical dysmorphology applications in diagnostics and training. [ABSTRACT FROM AUTHOR]

Background: Shifts in peak frequencies of oscillatory neural rhythms are put forward as a principal mechanism by which cross‐frequency coupling/decoupling is implemented in the brain. During active neural processing, functional integration is facilitated through transitory formations of "harmonic" cross‐frequency couplings, whereas "nonharmonic" decoupling among neural oscillatory rhythms is postulated to characterize the resting, default state of the brain, minimizing the occurrence of spurious, noisy, background couplings. Methods: Within this exploratory, randomized, placebo‐controlled trial, we assessed whether the transient occurrence of nonharmonic and harmonic relationships between peak‐frequencies in the alpha (8–14 Hz) and theta (4–8 Hz) bands is impacted by intranasal administration of oxytocin, a neuromodulator implicated in improving homeostasis and reducing stress/anxiety. To do so, resting‐state electroencephalography was acquired before and after 4 weeks of oxytocin administration (12 IU twice‐daily) in children with autism spectrum disorder (8–12 years, n = 33 oxytocin; n = 34 placebo). At the baseline, neural assessments of children with autism were compared with those of a matched cohort of children without autism (n = 40). Results: Compared to nonautistic peers, autistic children displayed a lower incidence of nonharmonic alpha‐theta cross‐frequency decoupling, indicating a higher incidence of spurious "noisy" coupling in their resting brain (p =.001). Dimensionally, increased neural coupling was associated with more social difficulties (p =.002) and lower activity of the parasympathetic "rest & digest" branch of the autonomic nervous system (p =.018), indexed with high‐frequency heart‐rate‐variability. Notably, after oxytocin administration, the transient formation of nonharmonic cross‐frequency configurations was increased in the cohort of autistic children (p <.001), indicating a beneficial effect of oxytocin on reducing spurious cross‐frequency‐interactions. Furthermore, parallel epigenetics changes of the oxytocin receptor gene indicated that the neural effects were likely mediated by changes in endogenous oxytocinergic signaling (p =.006). Conclusions: Chronic oxytocin induced important homeostatic changes in the resting‐state intrinsic neural frequency architecture, reflective of reduced noisy oscillatory couplings and improved signal‐to‐noise properties. [ABSTRACT FROM AUTHOR]

Two semi-structured parental interviews are available with algorithms developed to measure DSM-5 criteria of ASD, namely the Developmental, Dimensional and Diagnostic Interview (3di) and the Diagnostic Interview for Social and Communication Disorders (DISCO-11). The main aim of this study was to examine the agreement between classification according to both interviews, and their convergence with the clinical diagnosis. Therefore, the 3di and DISCO-11 were administered from three groups of parents of a 4-18 year old. Results showed 75% agreement between both instruments, but in the ASD group only 16% of the children scored above threshold on both instruments. Exploratory analyses suggested that the 3di failed to detect rigid and repetitive behaviors, whereas the DISCO-11 was insufficiently sensitive in detecting socio-communicative problems.

We objectively quantified the neural sensitivity of school-aged boys with and without autism spectrum disorder (ASD) to detect briefly presented fearful expressions by combining fast periodic visual stimulation with frequency-tagging electroencephalography. Images of neutral faces were presented at 6 Hz, periodically interleaved with fearful expressions at 1.2 Hz oddball rate. While both groups equally display the face inversion effect and mainly rely on information from the mouth to detect fearful expressions, boys with ASD generally show reduced neural responses to rapid changes in expression. At an individual level, fear discrimination responses predict clinical status with an 83% accuracy. This implicit and straightforward approach identifies subtle deficits that remain concealed in behavioral tasks, thereby opening new perspectives for clinical diagnosis.

Previous research suggested that adolescents with autism spectrum disorder are better than typically developing children in detecting local, non-social details within complex visual scenes. To better understand these differences, we used the image database by Sareen et al., containing the size and on-screen location information of all changes in the images, in a change blindness paradigm. In this task, an original and a modified real-world scene, separated by a gray blank, alternate repeatedly until observers detect the change. Our results indicated that participants with and without autism spectrum disorder performed similarly when scenes were presented upright, but that only the performance of the typically developing adolescents became worse in the inverted scene condition. In this condition, the correlation between performance and both image difficulty and change predictability was significantly weaker in autism spectrum disorder than in typically developing participants. We suggest that these findings result from a more locally biased search strategy in people with autism spectrum disorder, compared to typically developing participants, in tasks in which the rapid processing of global information does not help to improve change detection performance. Finally, although we found change location, change size, and age to influence participant performance, none of these was directly linked to the observed group-level differences.

Local and global visual processing abilities and processing style were investigated in individuals with autism spectrum disorder (ASD) versus typically developing individuals, children versus adolescents and boys versus girls. Individuals with ASD displayed more attention to detail in daily life, while laboratory tasks showed slightly reduced global processing abilities, intact local processing abilities, and a more locally oriented processing style. However, the presence of these group differences depended on particular task and sample (i.e., age and gender) characteristics. Most measures of local and global processing did not correlate with each other and were not associated with processing style. Significant associations between local-global processing and ASD symptom severity were observed, but the causality of these associations remains unclear.

The multiple object tracking (MOT) paradigm has proven its value in targeting a number of aspects of visual cognition. This study used MOT to investigate the effect of object-based grouping, both in children with and without autism spectrum disorder (ASD). A modified MOT task was administered to both groups, who had to track and distinguish four targets that moved randomly amongst four distracters, irrespective of the grouping condition. No group difference was revealed between children with and without ASD: both showed adequate MOT abilities and a similar amount of grouping interference. Implications of the current result are considered for previous MOT studies, the developmental trajectory of perceptual grouping, and the idea of heightened sensitivity to task characteristics in ASD.

Previous research has generally found lower wellbeing levels among parents of autistic children that were related to fewer positive and more negative parenting behaviours. However, these relationships have not yet been studied before a formal autism diagnosis is given. The present study investigates wellbeing (including positive mood, vitality, and general interest) and its relationships with a range of parenting behaviours among two groups of mothers with children at elevated likelihood (EL) of autism: mothers of younger siblings of children on the autism spectrum ('siblings'; n = 81) and very or extremely prematurely born children ('preterms'; n = 40). Growth curves were modelled to investigate whether wellbeing and EL group were associated with (change in) reported parenting behaviours between 10 and 24 months of child's age. As expected, we found more stability than change in parenting behaviours, and more similarities than group differences in parenting behaviours and wellbeing. Mothers generally reported more disciplinary behaviours when their child grew older, in line with general population findings. Initial levels of supportive behaviours were equally high among mothers of siblings and preterms, but only mothers of preterms reported an increase over time. Wellbeing levels were largely comparable to those of a matched subsample from the general population, contradicting previous findings. Contrary to our hypotheses, wellbeing was not associated with fewer positive or more negative parenting behaviours. This is encouraging, as all children benefit from supportive and responsive behaviours. Highlights: Among mothers of children at elevated likelihood of autism, most parenting behaviours did not change during the second year of life. Both mothers of siblings and preterms reported an increase in disciplinary behaviours. Additionally, mothers of preterms reported an increase in warm and supportive behaviours. No group differences were found in initial parenting behaviours and wellbeing or in change over time, except for warmth/support. Wellbeing was comparable to a matched general population subsample and not associated with any of the parenting behaviours. [ABSTRACT FROM AUTHOR]

Background: RASopathies are associated with an increased risk of autism spectrum disorder (ASD). For neurofibromatosis type 1 (NF1) there is ample evidence for this increased risk, while for other RASopathies this association has been studied less. No specific ASD profile has been delineated so far for RASopathies or a specific RASopathy individually. Methods: We conducted a systematic review to investigate whether a specific RASopathy is associated with a specific ASD profile, or if RASopathies altogether have a distinct ASD profile compared to idiopathic ASD (iASD). We searched PubMed, Web of Science, and Open Grey for data about ASD features in RASopathies and potential modifiers. Results: We included 41 articles on ASD features in NF1, Noonan syndrome (NS), Costello syndrome (CS), and cardio‐facio‐cutaneous syndrome (CFC). Individuals with NF1, NS, CS, and CFC on average have higher ASD symptomatology than healthy controls and unaffected siblings, though less than people with iASD. There is insufficient evidence for a distinct ASD phenotype in RASopathies compared to iASD or when RASopathies are compared with each other. We identified several potentially modifying factors of ASD symptoms in RASopathies. Conclusions: Our systematic review found no convincing evidence for a specific ASD profile in RASopathies compared to iASD, or in a specific RASopathy compared to other RASopathies. However, we identified important limitations in the research literature which may also account for this result. These limitations are discussed and recommendations for future research are formulated. [ABSTRACT FROM AUTHOR]

While most typically developing (TD) participants have a coarse-to-fine processing style, people with autism spectrum disorder (ASD) seem to be less globally and more locally biased when processing visual information. The stimulus-specific spatial frequency content might be directly relevant to determine this temporal hierarchy of visual information processing in people with and without ASD. We implemented a semantic priming task in which (in)congruent coarse and/or fine spatial information preceded target categorization. Our results indicated that adolescents with ASD made more categorization errors than TD adolescents and needed more time to process the prime stimuli. Simultaneously, however, our findings argued for a processing advantage in ASD, when the prime stimulus contains detailed spatial information and presentation time permits explicit visual processing.