Autism and attention deficit hyperactivity disorder: assessing attention and response control with the integrated visual and auditory continuous performance test.

Symptoms of attention deficit hyperactivity disorder (ADHD) have been widely reported in children with autism spectrum disorder (ASD). The current study investigated attention and response control in children with ASD, ADHD, and typical development using the Integrated Visual and Auditory Continuous Performance Test. Results indicate that many children with ASD show significant deficits in visual and auditory attention and greater deficits in impulsivity than children with ADHD or typical development. These findings suggest that many of the children with ASD demonstrate significant ADHD-like deficits. These findings are discussed in the context of symptoms, subtypes, and comorbidity.     

Overlapping and Distinct Cognitive Impairments in Attention-Deficit/Hyperactivity and Autism Spectrum Disorder without Intellectual Disability

Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are commonly comorbid, share genetic liability, and often exhibit overlapping cognitive impairments. Clarification of shared and distinct cognitive effects while considering comorbid symptoms across disorders has been lacking. In the current study, children ages 7–15 years assigned to three diagnostic groups:ADHD (n?=?509), ASD (n?=?97), and controls (n?=?301) completed measures spanning the cognitive domains of attention/arousal, working memory, set-shifting, inhibition, and response variability. Specific processes contributing to response variability were examined using a drift diffusion model, which separately quantified drift rate (i.e., efficiency of information processing), boundary separation (i.e., speed-accuracy trade-offs), and non-decision time. Children with ADHD and ASD were impaired on attention/arousal, processing speed, working memory, and response inhibition, but did not differ from controls on measures of delayed reward discounting, set-shifting, or interference control. Overall, impairments in the ASD group were not attributable to ADHD symptoms using either continuous symptom measures or latent categorical grouping approaches. Similarly, impairments in the ADHD group were not attributable to ASD symptoms. When specific RT parameters were considered, children with ADHD and ASD shared impairments in drift rate. However, children with ASD were uniquely characterized by a wider boundary separation. Findings suggest a combination of overlapping and unique patterns of cognitive impairment for children with ASD as compared to those with ADHD, particularly when the processes underlying reaction time measures are considered separately.     

The Association between Self-Regulation and Symptoms of Autism Spectrum Disorder in Preschoolers with Externalizing Behavior Problems

The purpose of the current study was to examine the role of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) symptoms in predicting deficits in self-regulation across the domains of executive functioning and emotion regulation. Parents of 40 preschoolers with externalizing behavior problems reported on children’s ADHD and ASD symptoms, and emotion regulation. Children completed a standardized executive functioning battery. Results indicated that 28% of parents and 53% of teachers rated children above the subclinical range on ASD symptoms. An interaction emerged such that higher ASD symptoms were only associated with poorer executive functioning for children with lower ADHD symptoms. However, ASD symptoms were predictive of poorer emotion regulation independent of ADHD symptoms. Findings revealed clinically significant ASD symptoms, which aided in explaining heterogeneity in self-regulation deficits.     

Sluggish cognitive tempo in children and adolescents with higher functioning autism spectrum disorders: Social impairments and internalizing symptoms

Sluggish cognitive tempo (SCT) was introduced in 1980s in the field of attention deficit hyperactivity disorder (ADHD). Studies indicate that symptoms of SCT are separate from symptoms of ADHD and independently associated with multiple domains of functioning in clinical groups and in typical development. We assessed whether similar pattern would apply to higher functioning autism spectrum disorders (ASD). Children with higher functioning ASD (N = 55; 5?15 years) were divided into the ASD+High SCT (n = 17), the ASD+Medium SCT (n = 18) and the ASD+Low SCT (n = 20) groups based on parent‐rated daydreaming and slowness on the Five to Fifteen questionnaire (FTF). The groups were compared on SCT‐related impairments found in previous studies: social skills, academic functioning, psychiatric symptoms, and processing speed. Assessment methods were the FTF, the Development and Well‐Being Assessment, and the Coding subtest of the WISC‐III. The ADHD symptoms were statistically controlled due to the overlap between SCT and ADHD. The ASD+High SCT and ASD+Medium SCT groups were significantly more likely to have the most pronounced social impairments, and the ASD+High SCT group had significantly higher rate of internalizing disorders compared to the ASD+Low SCT group. Our results suggest that children with higher functioning ASD and high or medium levels of SCT symptoms could be at higher risk for psychosocial impairments than children with higher functioning ASD with low levels of SCT symptoms. Co‐occurring ADHD symptoms do not explain the finding. Recognizing SCT symptoms in higher functioning ASD would be important to targeting preventive support.     

孤独症谱系障碍者视觉定向与视觉搜索的特点及神经机制

定向网络是注意网络的重要组成部分, 主要包括视觉定向与视觉搜索两大任务。对于这两大注意任务, 正常个体在神经机制上存在较大的重叠, 然而, 孤独症个体却表现出截然相反的行为证据。研究者从非社会信息的注意视角发现, 一般而言, 在视觉定向上, 孤独症个体注意转移不存在缺陷, 而注意脱离存在困难, 但该结论仍有争议; 在视觉搜索上, 孤独症个体存在视觉搜索优势, 但该优势发生的阶段及原因仍需进一步探究。未来研究应进一步考察孤独症个体在视觉定向任务中左右视野的不对称性、视觉搜索优势的内在机制及两大注意任务之间的相互关系。     

Bottom-up and top-down control in visual search

Previous research suggests that the allocation of attention is largely controlled either in a stimulus-driven or in a goal-driven manner. To date, few studies have systematically manipulated variables affecting stimulus-driven and goal-driven selection independently in order to investigate how both manners of control interrelate and affect performance in visual search. In the present study observers were presented with search displays consisting of an array of line segments rotated at various orientations. The task of observers was to indicate the presence or absence of a vertical line segment (the target) presented amongst a series of nontargets and possibly one distractor. By varying the absolute differences in orientation between the target, nontargets, and distractors, relative target-distractor salience and target-distractor similarity were independently manipulated to investigate the contribution of stimulus-driven and goal-driven control. The major result was that relative target-distractor salience and target-distractor similarity affected search performance independently. Performance was better in cases where the irrelevant distractor was not a salient item in the search display and did not look similar to the target. The results are discussed in terms of models of attentional control.     

Categorical effects in children's colour search: A cross‐linguistic comparison

In adults, visual search for a colour target is facilitated if the target and distractors fall in different colour categories (e.g. Daoutis, Pilling, & Davies, in press ). The present study explored category effects in children's colour search. The relationship between linguistic colour categories and perceptual categories was addressed by comparing native speakers of languages differing in the number of colour terms. Experiment 1 compared English and Kwanyama (Namibian) children aged 4 to 7 years on a visual search task, using target‐distractor pairs (blue‐green, blue‐purple, red‐pink) for which the Kwanyama did not have distinct names. The presence of a category advantage in the English, but not in the Kwanyama, suggested that linguistic boundaries may affect search performance. Experiment 2 examined visual search performance in the green‐yellow and the blue‐green region, in English and Himba (Namibian) 6‐year‐olds. The number of distractors was varied to assess search efficiency. Cross‐category search was more efficient than within‐category search in the English group, but this advantage was absent in the Himba. Increasing the number of distractors affected search speed in the English group, but not in the Himba. Overall, these findings suggest cross‐language differences in categorical effects on colour search, but also in the way the children performed the search. The nature of the category effect in search is discussed with respect to these findings.     

Why is visual search superior in autism spectrum disorder?

This study investigated the possibility that enhanced memory for rejected distractor locations underlies the superior visual search skills exhibited by individuals with autism spectrum disorder (ASD). We compared the performance of 21 children with ASD and 21 age‐ and IQ‐matched typically developing (TD) children in a standard static search task and a dynamic search task, in which targets and distractors randomly changed locations every 500 ms, precluding the use of memory in search. Children with ASD exhibited overall faster reaction time (RT) relative to TD children, and showed no disruption in search efficiency in the dynamic condition, discounting the possibility that memory for rejected distractors augments their visual search abilities. Analyses of RT x set size functions showed no group differences in slopes but lower intercepts for the ASD group in both static and dynamic search, suggesting that the ASD advantage derived from non‐search processes, such as an enhanced ability to discriminate between targets and distractors at the locus of attention. Eye‐movement analyses revealed that the ASD and TD groups were similar in the number and spatial distribution of fixations across the search array, but that fixation duration was significantly shorter among children with ASD. Lower intercepts in static search were related to increased symptom severity in children with ASD. In summary, ASD search superiority did not derive from differences in the manner in which individuals with ASD deployed their attention while searching, but from anomalously enhanced perception of stimulus features, which was in turn positively associated with autism symptom severity.     

Teaching children with autism spectrum disorder to tact olfactory stimuli

Research on tact acquisition by children with autism spectrum disorder (ASD) has often focused on teaching participants to tact visual stimuli. It is important to evaluate procedures for teaching tacts of nonvisual stimuli (e.g., olfactory, tactile). The purpose of the current study was to extend the literature on secondary target instruction and tact training by evaluating the effects of a discrete‐trial instruction procedure involving (a) echoic prompts, a constant prompt delay, and error correction for primary targets; (b) inclusion of secondary target stimuli in the consequent portion of learning trials; and (c) multiple exemplar training on the acquisition of item tacts of olfactory stimuli, emergence of category tacts of olfactory stimuli, generalization of category tacts, and emergence of category matching, with three children diagnosed with ASD. Results showed that all participants learned the item and category tacts following teaching, participants demonstrated generalization across category tacts, and category matching emerged for all participants.     

Emotional face recognition in autism and in cerebral visual impairments: In search for specificity

Autism spectrum disorder (ASD) is characterized by difficulties in the social domain, but also by hyper- and hypo-reactivity. Atypical visual behaviours and processing have often been observed. Nevertheless, several similar signs are also identified in other clinical conditions including cerebral visual impairments (CVI). In the present study, we investigated emotional face categorization in groups of children with ASD and CVI by comparing each group to typically developing individuals (TD) in two tasks. Stimuli were either non-filtered or filtered by low- and high-spatial frequencies (LSF and HSF). All participants completed the autism spectrum quotient score (AQ) and a complete neurovisual evaluation. The results show that while both clinical groups presented difficulties in the emotional face recognition tasks and atypical processing of filtered stimuli, they did not differ from one another. Additionally, autistic traits were observed in the CVI group and symmetrically, some visual disturbances were present in the ASD group as measured via the AQ score and a neurovisual evaluation, respectively. The present study suggests the relevance of comparing ASD to CVI by showing that emotional face categorization difficulties should not be solely considered as autism-specific but merit investigation for potential dysfunction of the visual processing neural network. These results are of interest in both clinical and research perspectives, indicating that systematic visual examination is warranted for individuals with ASD.     

A Comparison of Structural Brain Imaging Findings in Autism Spectrum Disorder and Attention-Deficit Hyperactivity Disorder

ASD and ADHD are regarded as distinct disorders in the current DSM-5. However, recent research and the RDoC initiative are recognizing considerable overlap in the clinical presentation of ASD, ADHD, and other neurodevelopmental disorders. In spite of numerous neuroimaging findings in ASD and ADHD, the extent to which either of the above views are supported remains equivocal. Here we compare structural MRI and DTI literature in ASD and ADHD. Our main findings reveal both distinct and shared neural features. Distinct expressions were in total brain volume (ASD: increased volume, ADHD: decreased volume), amygdala (ASD: overgrowth, ADHD: normal), and internal capsule (ASD: unclear, ADHD: reduced FA in DTI). Considerable overlap was noted in the corpus callosum and cerebellum (lower volume in structural MRI and decreased FA in DTI), and superior longitudinal fasciculus (reduced FA in DTI). In addition, we identify brain regions which have not been studied in depth and require more research. We discuss relationships between brain features and symptomatology. We conclude by addressing limitations of current neuroimaging research and offer approaches that account for clinical heterogeneity to better distinguish brain-behavior relationships.     

Temporal discounting of monetary rewards in children and adolescents with ADHD and autism spectrum disorders

It has been difficult to differentiate attention‐deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) in terms of some aspects of their cognitive profile. While both show deficits in executive functions, it has been suggested that they may differ in their response to monetary reward. For instance, children with ADHD prefer small immediate over large delayed rewards more than typically developing controls. One explanation for this is that they discount the value of rewards to a higher degree as they are moved into the future. The current study investigated whether children with ADHD can be differentiated from those with ASD in terms of reward discounting. Thirty‐nine children (8–16 y) with ADHD, 34 children with ASD and 46 typically developing controls performed a hypothetical monetary temporal discounting task. Participants were instructed to make repeated choices between small variable rewards (0, 5, 10, 20, 30€) delivered immediately and large rewards delivered after a variable delay. Children with ADHD but not ASD discounted future rewards at a higher rate than typically developing controls. These data confirm steeper discounting of future rewards in ADHD and add to a small but growing literature showing that the psychological profile of ADHD can be distinguished from that of ASD in terms of disrupted motivational processes.     

Callous-Unemotional Traits are Uniquely Associated with Poorer Peer Functioning in School-Aged Children

This study examines externalizing symptoms (attention-deficit/hyperactivity disorder [ADHD], conduct problems, and callous-unemotional [CU] traits) in relation to domains of peer functioning (social competence, loneliness, and close friendship quality), with a specific focus on the role of CU traits. One hundred twenty-four elementary students (grades 3–6; 45% boys) completed multiple measures of peer functioning, and teachers completed measures of externalizing symptoms and social competence. After controlling for demographic variables and other externalizing symptoms, CU traits were significantly associated with poorer peer functioning across all variables except for demands of exclusivity in close friendships. ADHD symptoms were also uniquely associated with poorer social functioning across a number of variables. In contrast, conduct problems were at times associated with better social functioning after controlling for the effects of other externalizing problems. These findings bolster the importance of developing and evaluating social skills interventions for children displaying elevated CU traits.     

Visual search is not blind to emotion

A series of three visual search tasks revealed more efficient search for hostile than for peaceful faces among neutral face distractors. Given that this effect has been observed inconsistently in prior literature, meta-analytic methods were employed for evaluating data across three experiments in order to develop a more valid estimate of the potentially small effect size. Furthermore, in the present experiments, different emotional meanings were conditioned to identical faces across observers, thus eliminating confounds between the physical characteristics and the emotional valences of the face stimuli. On the basis of the present findings, we argue that the visual system is capable of determining a face's emotional valence before the face becomes the focus of attention, and that emotional valence can be used by the visual system to determine subsequent attention allocation. However, meta-analytic results indicate that emotional valence makes a relatively small contribution to search efficiency in the present search context.     

Yoga,Mindfulness, and Meditation Interventions for Youth with ADHD: Systematic Review and Meta-Analysis

Attention-deficit/hyperactivity disorder (ADHD) is a chronic developmental disorder affecting 3–7% of children. In light of the growing utilization of yoga, mindfulness, and meditation in ADHD populations and potential benefits it has on ADHD symptoms, executive function deficits, and social functioning, we sought to evaluate these interventions for youth with ADHD. The primary aim of this review paper is to identify the efficacy of these programs for the treatment of youth with ADHD through a systematic review and meta-analysis. A systematic literature search was conducted in the following electronic databases: PsychINFO, ERIC, PubMed, and MEDLINE. Studies were included in the meta-analytic review if participants were between 5–17 years old, had a diagnosis of ADHD or met symptom threshold on psychometrically-validated measure of ADHD symptoms, was a treatment outcome study, and was published in a peer-reviewed English-language journal. The effect sizes of eleven studies demonstrate that yoga, mindfulness-based interventions, and/or meditation had a statistically significant effect on the outcomes of ADHD symptoms, hyperactivity, and inattention (parent and teacher report), as well as parent-child relationship, executive functioning, on-task behavior, parent stress, and parent trait-mindfulness (p?<?0.05). The effect sizes range from small to large effects across these outcomes. Considerable risk for bias was found across studies. Given significant methodological limitations of the literature, positive effect sizes found in studies should be interpreted with caution; these interventions should not be considered first-line interventions for ADHD. However, preliminary findings suggest yoga, mindfulness, and meditation may be beneficial for youth with ADHD, but extensive research is required to validate the efficacy of these interventions.     

Three Dimensions of Oppositionality in Autism Spectrum Disorder

In autism spectrum disorder (ASD), symptoms of oppositional defiant disorder (ODD) are common but poorly understood. DSM-5 has adopted a tripartite model of ODD, parsing its features into ‘angry and irritable symptoms’ (AIS), ‘argumentative and defiant behavior’ (ADB) and ‘vindictiveness’. This was based on findings in non-autistic populations that each of these dimensions of oppositionality has a distinct constellation of associations with internalising and externalising psychopathology. We applied the tripartite DSM-5 ODD model to ASD to test its generalisability beyond non-ASD populations; and to elucidate the nature of ODD symptoms in ASD. Participants were 216 verbally-fluent young people (mean age?=?9.6 years, range 3.0 to 16.2 years, 82 % male) with ASD. Cross-sectional parent-and teacher-report data were analysed using bootstrap multiple regression to test the following predictions, derived from studies of non-ASD young people: (1) AIS will be the main predictor of internalising problems; (2) ADB will be the main predictor of ADHD symptoms; (3) all ODD traits will independently predict conduct disorder symptoms; (4) vindictiveness will be the main predictor of aggressive conduct problems. Our findings using both parent and teacher data were consistent with the non-ASD ODD literature. AIS were associated with internalising but not externalising problems; ADB and vindictiveness were associated with externalising but not internalising problems; and vindictiveness was the main predictor of aggression. The DSM-5 tripartite model of ODD appears to be generalisable to ASD: for people with an autistic disorder, AIS, ADB and vindictive dimensions of oppositionality have distinct associations with concurrent psychopathology, suggesting the need to assess them as separate constructs.     

任务难度对自闭症儿童视觉搜索优势显现的影响

探究自闭症谱系障碍(ASD)儿童视觉搜索优势的显现是否受任务难度影响及优势存在机理。本研究采集ASD和正常发育(TD)儿童完成不同难度等级视觉搜索任务的行为和眼动数据。结果发现：在高难度等级任务中ASD组的准确率显著高于TD组;ASD组在任务中对目标刺激的回视次数、对靶子和外周感兴趣区的注视时间显著少于TD组,且ASD组偏好注视刺激的右侧区域。结果表明ASD儿童视觉搜索优势显现受任务难度影响,且可能与其对干扰刺激增强的知觉能力有关。     

Visual search for drowning swimmers: Investigating the impact of lifeguarding experience

How does domain expertise influence dynamic visual search? Previous studies of visual search often use abstract search arrays that are devoid of applied context, with comparatively few studies exploring applied naturalistic and dynamic settings. The current research adds to this literature by examining lifeguard drowning‐detection across two studies using naturalistic, dynamic search tasks. Behavioural responses and eye‐movement data were recorded as participants watched staged video clips and attempted to identify if a swimmer was drowning. The results demonstrate lifeguard superiority in response times to drowning events, compared to non‐lifeguards. No differences between lifeguard and non‐lifeguard eye‐movements were noted however. This suggests that the experiential benefit in response times results from other underlying processes, rather than any scanning benefits. This research highlights the complex nature of naturalistic and dynamic searches, while demonstrating the robust nature of simulated videos in producing experience effects in visual search.     

Visual search and foraging compared in a large-scale search task

It has been argued that visual search is a valid model for human foraging. However, the two tasks differ greatly in terms of the coding of space and the effort required to search. Here we describe a direct comparison between visually guided searches (as studied in visual search tasks) and foraging that is not based upon a visually distinct target, within the same context. The experiment was conducted in a novel apparatus, where search locations were indicated by an array of lights embedded in the floor. In visually guided conditions participants searched for a target defined by the presence of a feature (red target amongst green distractors) or the absence of a feature (green target amongst red and green distractors). Despite the expanded search scale and the different response requirements, these conditions followed the pattern found in conventional visual search paradigms: feature-present search latencies were not linearly related to display size, whereas feature-absent searches were longer as the number of distractors increased. In a non-visually guided foraging condition, participants searched for a target that was only visible once the switch was activated. This resulted in far longer latencies that rose markedly with display size. Compared to eye-movements in previous visual search studies, there were few revisit errors to previously inspected locations in this condition. This demonstrates the important distinction between visually guided and non-visually guided foraging processes, and shows that the visual search paradigm is an equivocal model for general search in any context. We suggest a comprehensive model of human spatial search behaviour needs to include search at a small and large scale as well as visually guided and non-visually guided search.     

Disorganized Attachment and Inhibitory Capacity: Predicting Externalizing Problem Behaviors

The aim of the present study was to investigate whether attachment insecurity, focusing on disorganized attachment, and the executive function (EF) component of inhibition, assessed at age 5, were longitudinally related to general externalizing problem behaviors as well as to specific symptoms of ADHD and Autism spectrum disorder (ASD), and callous-unemotional (CU) traits. General externalizing problem behaviors were also measured at age 5 to allow for a developmental analysis. Outcome variables were rated by parents and teachers. The sample consisted of 65 children with an oversampling of children with high levels of externalizing behaviors. Attachment was evaluated using a story stem attachment doll play procedure. Inhibition was measured using four different tasks. The results showed that both disorganized attachment and poor inhibition were longitudinally related to all outcome variables. Controlling for initial level of externalizing problem behavior, poor inhibition predicted ADHD symptoms and externalizing problem behaviors, independent of disorganized attachment, whereas for ASD symptoms no predictive relations remained. Disorganized attachment independently predicted CU traits.