Visual search and autism symptoms: What young children search for and co-occurring ADHD matter

Symptoms of ADHD and Autism Spectrum Disorder Interactively Predict Children's Verbal Fluency

OBJECTIVE

Verbal fluency, the capacity to generate words from a designated category, predicts myriad cognitive and life outcomes. The study investigated verbal fluency in children with ADHD, autism spectrum disorder (ASD), and comorbid ADHD and ASD, to understand how ADHD- and ASD-related symptoms individually and jointly predict verbal fluency, and the underlying linguistic and cognitive substrates.

METHOD

Thirty-three school-aged children with ADHD, 27 with ASD, 25 with comorbid ADHD and ASD, and 39 with typical development, were assessed for ADHD and ASD symptoms and completed a semantic verbal fluency task.

RESULTS

Findings indicated that ADHD and ASD symptoms, especially ADHD hyperactivity-impulsivity symptoms and language-related ASD symptoms, interactively predicted verbal fluency across diagnostic groups.

CONCLUSION

The study implicated the potential cognitive and linguistic mechanisms underlying verbal fluency differences in ADHD and/or ASD, and clinical practices on enhancing verbal fluency in these clinical groups.

How Do Children and Adolescents with ASD Look at Animals? A Scoping Review

Autism spectrum disorder (ASD) is characterized by interaction and communication differences, entailing visual attention skill specificities. Interactions with animals, such as in animal-assisted interventions or with service dogs, have been shown to be beneficial for individuals with ASD. While interacting with humans poses challenges for them, engaging with animals appears to be different. One hypothesis suggests that differences between individuals with ASD's visual attention to humans and to animals may contribute to these interaction differences. We propose a scoping review of the research on the visual attention to animals of youths with ASD. The objective is to review the methodologies and tools used to explore such questions, to summarize the main results, to explore which factors may contribute to the differences reported in the studies, and to deduce how youth with ASD observe animals. Utilizing strict inclusion criteria, we examined databases between 1942 and 2023, identifying 21 studies in international peer-reviewed journals. Three main themes were identified: attentional engagement and detection, visual exploration, and behavior. Collectively, our findings suggest that the visual attention of youths with ASD towards animals appears comparable to that of neurotypical peers, at least in 2D pictures (i.e., eye gaze patterns). Future studies should explore whether these results extend to real-life interactions.

The Effect of Spatial Uncertainty on Visual Search in Older School-Aged Children with and without ADHD

OBJECTIVE

Numerous studies support that simple visual search tests may not be sufficient to differentiate children with and without attention-deficit/hyperactivity disorder (ADHD), especially for older school-aged children. This study aimed to explore whether the high spatial uncertainty visual search tasks can effectively discriminate older school-aged children with ADHD from their typically developing (TD) peers.

METHOD

In a randomized, two-period crossover design, 122 school-aged children (61 ADHD and 61 TD subjects), aged 10-12 years old, were measured using comparable visual search tasks with structured and unstructured layouts.

RESULTS

First, the discriminant effectiveness of unstructured visual search tasks, which are associated with high-level spatial uncertainty, is superior to structured ones. Second, combining accuracy and speed into a Q score is a more sensitive measure than accuracy or time calculated alone in visual search tasks. A more in-depth ROC analysis showed that all variables could accurately identify ADHD from their TD peers under unstructured visual search tasks, with the index of the Q score performing best (AUR = 0.956). Third, the development of detectability, which represents the ability to distinguish between target and non-target, is approaching maturity in 10-12-year-old children with ADHD. However, these children showed severe deficits in dealing with disorganized distractors when performing visual search tasks with high-level spatial uncertainty.

CONCLUSIONS

The findings of this study support that older school-aged children with ADHD demonstrate less efficient search performance than their TD peers in complex/difficult visual search tasks, especially under higher spatial uncertainty.

High-level visual search in children with autism

Visual search has been classified as easy feature search, with rapid target detection and little set size dependence, versus slower difficult search with focused attention, with set size-dependent speed. Reverse hierarchy theory attributes these classes to rapid high cortical-level vision at a glance versus low-level vision with scrutiny, attributing easy search to high-level representations. Accordingly, faces "pop out" of heterogeneous object photographs. Individuals with autism have difficulties recognizing faces, and we now asked if this disability disturbs their search for faces. We compare search times and set size slopes for children with autism spectrum disorders (ASDs) and those with neurotypical development (NT) when searching for faces. Human face targets were found rapidly, with shallow set size slopes. The between-group difference between slopes (18.8 vs. 11.3 ms/item) is significant, suggesting that faces may not "pop out" as easily, but in our view does not warrant classifying ASD face search as categorically different from that of NT children. We also tested search for different target categories, dog and lion faces, and nonface basic categories, cars and houses. The ASD group was generally a bit slower than the NT group, and their slopes were somewhat steeper. Nevertheless, the overall dependencies on target category were similar: human face search fastest, nonface categories slowest, and dog and lion faces in between. We conclude that autism may spare vision at a glance, including face detection, despite its reported effects on face recognition, which may require vision with scrutiny. This dichotomy is consistent with the two perceptual modes suggested by reverse hierarchy theory.

Systematic Review and Meta-analysis: The Science of Early-Life Precursors and Interventions for Attention-Deficit/Hyperactivity Disorder

OBJECTIVE

To evaluate which early neurocognitive and behavioral precursors are associated with the development of attention-deficit/hyperactivity disorder (ADHD) and whether these are currently targeted in early interventions.

METHOD

We conducted 2 systematic reviews and meta-analyses of empirical studies to examine the following: (1) early-life (0-5 years) neurocognitive and behavioral precursors associated with familial likelihood for ADHD, an early ADHD diagnosis/elevated ADHD symptoms, and/or the presence of later-childhood ADHD; and (2) interventions delivered to children aged 0 to 5 years targeting the identified precursors or measuring these as outcomes. Standardized mean differences (Hedges' g) and pre-post-treatment change scores (SMD) were computed.

RESULTS

A total of 149 studies (165,095 participants) investigating 8 neurocognitive and behavioral domains met inclusion criteria for part 1. Multi-level random-effects meta-analyses on 136 studies revealed significant associations between ADHD and poorer cognitive (g = -0.46 [95% CIs: -0.59, -0.33]), motor (g = -0.35 [CIs: -0.48, -0.21]) and language (g = -0.43 [CIs: -0.66, -0.19]) development, social (g = 0.23 [CIs: 0.03, 0.43]) and emotional (g = 0.46 [CIs: 0.33, 0.58]) difficulties, early regulatory (g = 0.30 [CIs: 0.18, 0.43]) and sleep (g = 0.29 [CIs: 0.14, 0.44]) problems, sensory atypicalities (g = 0.52 [CIs: 0.16, 0.88]), elevated activity levels (g = 0.54 [CIs: 0.37, 0.72]), and executive function difficulties (g = 0.34 [CIs: 0.05, 0.64] to -0.87 [CIs: -1.35, -0.40]). A total of 32 trials (28 randomized, 4 nonrandomized, 3,848 participants) testing early interventions that targeted the identified precursors met inclusion criteria for part 2. Multi-level random-effects meta-analyses on 22 studies revealed significant intervention-related improvements in ADHD symptoms (SMD = 0.43 [CIs: 0.22, 0.64]) and working memory (SMD = 0.37 [CIs: 0.06, 0.69]).

CONCLUSION

Children aged 0 to 5 years with current or later-emerging ADHD are likely to experience difficulties in multiple neurocognitive/behavioral functions. Early interventions show some effectiveness in reducing ADHD symptoms, but their effects on neurocognitive/behavioral difficulties require further study.

Domain-general and domain-specific influences on emerging numerical cognition: Contrasting uni-and bidirectional prediction models

Domain-general skills such as executive functions (EFs), and domain-specific skills such as non-symbolic number sense and symbolic understanding are often pitted against each other as predictors of emerging maths. Here we aimed to investigate early childhood relations between these foundational skills with a balanced, longitudinal design. One hundred and seventy 3- and 4-year-old-children were tested at two time points, 5 months apart, on four domain-general executive and five domain-specific numeracy tasks. A latent EF factor was a strong predictor of symbolic maths and of their growth. In addition, stronger symbolic maths at Time 1 was correlated with later stronger EF, but symbolic maths did not predict EF growth. Our findings provide novel insights into dynamic interplay between general and specific cognitive skills contributing to preschool maths.

Visual search in ADHD, ASD and ASD + ADHD: overlapping or dissociating disorders?

Recent debates in the literature discuss commonalities between Attention-Deficit/Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) at multiple levels of putative causal networks. This debate requires systematic comparisons between these disorders that have been studied in isolation in the past, employing potential markers of each disorder to be investigated in tandem. The present study, choose superior local processing, typical to ASD, and increased Intra-Subject Variability (ISV), typical to ADHD, for a head-to-head comparison of the two disorders, while also considering the comorbid cases. It directly examined groups of participants aged 10-13 years with ADHD, ASD with (ASD+) or without (ASD-) comorbid ADHD and a typically developing (TD) group (total N = 85). A visual search task consisting of an array of paired words was designed. The participants needed to find the specific pair of words, where the first word in the pair was the cue word. This visual search task was selected to compare these groups on overall search performance and trial-to-trial variability of search performance (i.e., ISV). Additionally, scanpath analysis was also carried out using Recurrence Quantification Analysis (RQA) and the Multi-Match Model. Results show that only the ASD- group exhibited superior search performance; whereas, only the groups with ADHD symptoms showed increased ISV. These findings point towards a double dissociation between ASD and ADHD, and argue against an overlap between ASD and ADHD.

Early behavioral indices of inherited liability to autism

OBJECTIVE

The observed heterogeneity of autism spectrum disorder (ASD)-and the diversity of rare germline mutations with which it has been associated-has been difficult to reconcile with knowledge of its pronounced heritability in the population.

METHODS

This article reviews and synthesizes recent family and developmental studies incorporating behavioral indices of inherited risk for ASD.

RESULTS

Autism may arise from critical combinations of early inherited neurobehavioral susceptibilities-some specific to autism, some not-each of which may be traceable to partially-independent sets of genetic variation. These susceptibilities and their respective genetic origins may not relate to the characterizing symptoms of autism (after it develops) in a straightforward way, and may account for "missing heritability" in molecular genetic studies.

CONCLUSIONS

Within-individual aggregations of a finite set of early inherited neurobehavioral susceptibilities-each individually common in the population-may account for a significant share of the heritability of ASD. Comprehensive identification of these underlying traits my help elucidate specific early intervention targets in individual patients, especially if autism represents a developmental consequence of earlier-interacting susceptibilities. Scientific understanding of the early ontogeny of autism will benefit from epidemiologically-rigorous, genetically-informative studies of robust endophenotypic candidates whose inter-relationships in infancy are mapped and normed.