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Neuroimaging studies have uncovered structural and functional alterations in the cingulate cortex in individuals with autism spectrum disorders (ASD). Such abnormalities may underlie neurochemical imbalance. In order to characterize the neurochemical profile, the current study examined the concentration of brain metabolites in dorsal ACC (dACC) and posterior cingulate cortex (PCC) in high-functioning adults with ASD. Twenty high-functioning adults with ASD and 20 age-and-IQ-matched typically developing (TD) peers participated in this Proton magnetic resonance spectroscopy (1H-MRS) study. LCModel was used in analyzing the spectra to measure the levels of N-Acetyl aspartate (NAA), choline (Cho), creatine (Cr), and glutamate/glutamine (Glx) in dACC and PCC. Groups were compared using means for the ratio of each metabolite to their respective Cr levels as well as on absolute internal-water-referenced measures of each metabolite. There was a significant increase in Cho in PCC for ASD adults, with a marginal increase in dACC. A reduction in NAA/Cr in dACC was found in ASD participants, compared to their TD peers. No significant differences in Glx/Cr or Cho/Cr were found in dACC. There were no statistically significant group differences in the absolute concentration of NAA, Cr, Glx, or NAA/Cr, Cho/Cr, and Glx/Cr in the PCC. Differences in the metabolic properties of dACC compared to PCC were also found. Results of this study provide evidence for possible cellular and metabolic differences in the dACC and PCC in adults with ASD. This may suggest neuronal dysfunction in these regions and may contribute to the neuropathology of ASD. Autism Res 2016, 9: 643-657. © 2015 International Society for Autism Research, Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Deficits in language comprehension have been widely reported in children with autism spectrum disorders (ASD), with behavioral and neuroimaging studies finding increased reliance on visuospatial processing to aid in language comprehension. However, no study to date, has taken advantage of this strength in visuospatial processing to improve language comprehension difficulties in ASD. This study used a translational neuroimaging approach to test the role of a visual imagery-based reading intervention in improving the brain circuitry underlying language processing in children with ASD. Functional magnetic resonance imaging (MRI), in a longitudinal study design, was used to investigate intervention-related change in sentence comprehension, brain activation, and functional connectivity in three groups of participants (age 8-13 years): an experimental group of ASD children (ASD-EXP), a wait-list control group of ASD children (ASD-WLC), and a group of typically developing control children. After intervention, the ASD-EXP group showed significant increase in activity in visual and language areas and right-hemisphere language area homologues, putamen, and thalamus, suggestive of compensatory routes to increase proficiency in reading comprehension. Additionally, ASD children who had the most improvement in reading comprehension after intervention showed greater functional connectivity between left-hemisphere language areas, the middle temporal gyrus and inferior frontal gyrus while reading high imagery sentences. Thus, the findings of this study, which support the principles of dual coding theory [Paivio 2007], suggest the potential of a strength-based reading intervention in changing brain responses and facilitating better reading comprehension in ASD children. Autism Res 2015. © 2015 International Society for Autism Research, Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Interpreting emotional expressions appropriately poses a challenge for individuals with autism spectrum disorder (ASD). In particular, difficulties with emotional processing in ASD are more pronounced in contexts where emotional expressions are subtle, automatic, and reflexive-that is, implicit. In contrast, explicit emotional processing, which requires the cognitive evaluation of an emotional experience, appears to be relatively intact in individuals with ASD. In the present study, we examined the brain activation and functional connectivity differences underlying explicit and implicit emotional processing in age- and IQ-matched adults with ( n = 17) and without ( n = 15) ASD. Results indicated: (1) significantly reduced levels of brain activation in participants with ASD in medial prefrontal cortex (MPFC) and superior temporal gyrus (STG) during implicit emotion processing; (2) significantly weaker functional connectivity in the ASD group in connections of the MPFC with the amygdala, temporal lobe, parietal lobe, and fusiform gyrus; (3) No group difference in performance accuracy or reaction time; and (4) Significant positive relationship between empathizing ability and STG activity in ASD but not in typically developing participants. These findings suggest that the neural mechanisms underlying implicit, but not explicit, emotion processing may be altered at multiple levels in individuals with ASD. Autism Res 2015. © 2015 International Society for Autism Research, Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Motor-linked implicit learning is the learning of a sequence of movements without conscious awareness. Although motor symptoms are frequently reported in individuals with autism spectrum disorder ( ASD), recent behavioral studies have suggested that motor-linked implicit learning may be intact in ASD. The serial reaction time ( SRT) task is one of the most common measures of motor-linked implicit learning. The present study used a 3 T functional magnetic resonance imaging scanner to examine the behavioral and neural correlates of real-time motor sequence learning in adolescents and adults with ASD ( n = 15) compared with age- and intelligence quotient-matched individuals with typical development ( n = 15) during an SRT task. Behavioral results suggested less robust motor sequence learning in individuals with ASD. Group differences in brain activation suggested that individuals with ASD, relative to individuals with typical development, showed decreased activation in the right superior parietal lobule ( SPL) and right precuneus ( Brodmann areas 5 and 7, and extending into the intraparietal sulcus) during learning. Activation in these areas (and in areas such as the right putamen and right supramarginal gyrus) was found to be significantly related to behavioral learning in this task. Additionally, individuals with ASD who had more severe repetitive behavior/restricted interest symptoms demonstrated greater decreased activation in these regions during motor learning. In conjunction, these results suggest that the SPL may play an important role in motor learning and repetitive behavior in individuals with ASD. Autism Res 2015, 8: 38-51. © 2014 International Society for Autism Research, Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Memory consolidation is well known to occur during sleep, but might start immediately after encoding new information while awake. While consolidation processes are important across the lifespan, they may be even more important to maintain memory functioning in old age. We tested whether a novel measure of information processing known as network complexity might be sensitive to post-encoding consolidation mechanisms in a sample of young, middle-aged, and older adults. Network complexity was calculated by assessing the irregularity of brain signals within a network over time using multiscale entropy. To capture post-encoding mechanisms, network complexity was estimated using functional magnetic resonance imaging (fMRI) during rest before and after encoding of picture pairs, and subtracted between the two rest periods. Participants received a five-alternative-choice memory test to assess associative memory performance. Results indicated that aging was associated with an increase in network complexity from pre- to post-encoding in the default mode network (DMN). Increases in network complexity in the DMN also were associated with better subsequent memory across all age groups. These findings suggest that network complexity is sensitive to post-encoding consolidation mechanisms that enhance memory performance. These post-encoding mechanisms may represent a pathway to support memory performance in the face of overall memory declines. [ABSTRACT FROM AUTHOR]

Purpose: Differences in social cognition between autistic and nonautistic people may put autistic people at greater risk of being deceived. To inform communication interventions related to deception, the purposes of this mixed-methods study were to examine the deception detection strategies used by young adults with varying levels of autistic traits and to explore whether those strategies differed between groups or in terms of accuracy. Methods: Fifty-one young adults with varying levels of autistic traits watched a series of videos. For each video, the participant judged whether the recorded speaker was truthful and gave the reasoning for their judgment. Inductive thematic analysis was used to identify themes in participants’ stated reasons, which were used to quantitatively examine (1) between-group differences based on self-reported autistic traits and (2) theme-based differences in accuracy. Results: Thematic analysis of the open-ended responses yielded four major themes: subjective descriptions of the person, nonverbal communication, observable features of the response, and nebulous reasons. Statistical analyses indicated no significant group differences in frequency of use of the four themes. When the four themes were compared with each other, observable response features yielded significantly more accurate judgments than nonverbal communication or subjective descriptions. Discussion: Findings are discussed within the framework of speech–language pathologists’ role in helping communicators determine a speaker’s truthfulness, with the ultimate goal of avoiding deception and/or manipulation. Suggestions for incorporating research findings into the design of communication interventions are included. [ABSTRACT FROM AUTHOR]

Children with autism often have difficulty with Theory of Mind (ToM), the ability to infer mental states, and pragmatic skills, the contextual use of language. Neuroimaging research suggests ToM and pragmatic skills overlap, as the ability to understand another's mental state is a prerequisite to interpersonal communication. To our knowledge, no study in the last decade has examined this overlap further. To assess the emerging consensus across neuroimaging studies of ToM and pragmatic skills in autism, we used coordinate-based activation likelihood estimation (ALE) analysis of 35 functional magnetic resonance imaging (MRI) studies (13 pragmatic skills, 22 ToM), resulting in a meta-analysis of 1,295 participants (647 autistic, 648 non-autistic) aged 7 to 49 years. Group difference analysis revealed decreased left inferior frontal gyrus (LIFG) activation in autistic participants during pragmatic skills tasks. For ToM tasks, we found reduced anterior cingulate cortex (ACC), medial prefrontal cortex (MPFC), and temporoparietal junction (TPJ) activation in autistic participants. Collectively, both ToM and pragmatic tasks showed activation in IFG and superior temporal gyrus (STG) and a reduction in left hemispheric activation in autistic participants. Overall, the findings underscore the cognitive and neural processing similarities between ToM and pragmatic skills, and their underlying neurobiological differences in autism. [ABSTRACT FROM AUTHOR]

• This study examined brain activation during driving hazard detection. • Participants activated the social brain network when processing social hazards. • Autism, ADHD, and typical development groups did not differ in brain activation. • Driving experience predicted brain activation to social driving hazards. Driving is a cognitively challenging task, and many individuals with autism spectrum disorder (ASD) or with attention-deficit/hyperactivity disorder (ADHD) struggle to drive safely and effectively. Previous evidence suggests that core neuropsychological deficits in executive functioning (EF) and theory of mind (ToM) may impact driving in ASD and ADHD. This functional magnetic resonance imaging (fMRI) study compares the brain mechanisms underlying ToM and EF during a hazard perception driving task. Forty-six licensed drivers (14 ASD, 17 ADHD, 15 typically developing (TD)), ages 16–27 years, viewed a driving scenario in the MRI scanner and were instructed to respond to driving hazards that were either "social" (contained a human component such as a pedestrian) or "nonsocial" (physical objects such as a barrel). All groups of participants recruited regions part of the "social brain" (anterior insula, angular gyrus, right middle occipital gyrus, right cuneus/precuneus, and right inferior frontal gyrus) when processing social hazards, and regions associated with motor planning and object recognition (postcentral gyrus, precentral gyrus, and supplementary motor area) when processing nonsocial hazards. While there were no group differences in brain activation during the driving task, years licensed was predictive of greater prefrontal and temporal activation to social hazards in all participants. Findings of the current study suggest that high-functioning ASD and ADHD licensed drivers may be utilizing similar cognitive resources as TD controls for decisions related to driving-related hazard detection. [ABSTRACT FROM AUTHOR]

The human face communicates a wealth of socially relevant information such as person identity, emotion, and intention. A consistent behavioral finding in autism spectrum disorder (ASD) is reduced attention to or difficulty drawing meaning from faces. However, neuroimaging research into the neural correlates of face processing differences in ASD has returned mixed results. While many studies find hypo-activation or hypo-connectivity of core and extended face network regions, others show hyper-activation, equal activation, or even activation shifted to object-selective fusiform gyrus (FG) regions in ASD during face processing. This study consolidates two decades of literature to reveal common and consistent patterns of brain activation when viewing human faces in ASD. It also addresses whether face processing in ASD is routinely shifted to object-centric regions of the FG. To do so, we conducted an extensive search of the neuroimaging literature according to PRISMA guidelines. Peak activation coordinates from a final set of 23 studies, yielding a sample of 713 participants (338 ASD), were included for quantitative meta-analysis using Activation Likelihood Estimation (ALE). ASD within-group results across studies revealed a single activation cluster in the left FG, which presented laterally to the mid-fusiform sulcus (MFS). Typically developing groups displayed common activations across core and extended face network regions. Exploratory analysis of between group findings from the literature did not yield significant results. Overall, our results suggest that individuals with ASD consistently activate at least one typical face network region, the left FG, when processing faces and this activation is not routinely shifted to object-centric areas of the FG. • Activation likelihood estimation meta-analysis of face processing. • Core and extended face network activated in neurotypical groups across tasks. • Autism spectrum disorder activated only the left fusiform gyrus consistently. • Fusiform activation was lateral to the mid-fusiform sulcus in both groups. • No consistent shift to object-centric fusiform regions in autism spectrum disorder. [ABSTRACT FROM AUTHOR]

• Relationships between psychopathy and brain function during moral cognition in adolescence. • Functional MRI activation, seed-to-voxel and seed-to-seed connectivity analyses. • Insula activity is correlated with thrill-seeking in adolescents with disruptive behavior. • Social brain network connectivity during moral reasoning is related to psychopathy. • Reduced connectivity between social brain regions may have developmental implications. Brain functioning underlying moral decision-making in adolescents with psychopathic traits is relatively less understood. This fMRI study examined the neural correlates of moral decision-making in relation to psychopathic traits, as measured by the Youth Psychopathic Traits Inventory (YPI), in a sample of 16 community-recruited youth (mean age=13.94) with reported behavior problems. Participants viewed images that depicted a moral violation, a conflict with no moral violation, and a neutral scenario. We analyzed activation, seed-to-voxel, and seed-to-seed functional connectivity using a social brain mask during moral reasoning and decision-making. Results indicated: a) greater activity in social brain regions while assessing acts of moral, compared to nonmoral, violations; b) positive correlations between activation of several social brain regions and YPI subscale scores; c) a positive association between YPI and functional connectivity between the social brain network and the bilateral middle cingulate cortices; d) significant effects of YPI on connectivity between social brain regions and the rest of the brain; and e) decreased connectivity between several ROIs during moral reasoning: the left temporoparietal junction (lTPJ) and dorsomedial prefrontal cortex (DMPFC), the precuneus (PREC) and left amygdala (lAMYG), and the PREC and rAMYG. Clinical and developmental implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

Social neuroscience research has focused on an identified network of brain regions primarily associated with processing Theory of Mind (ToM). However, ToM is a broad cognitive process, which encompasses several sub-processes, such as mental state detection and intentional attribution, and the connectivity of brain regions underlying the broader ToM network in response to paradigms assessing these sub-processes requires further characterization. Standard fMRI analyses which focus only on brain activity cannot capture information about ToM processing at a network level. An alternative method, independent component analysis (ICA), is a data-driven technique used to isolate intrinsic connectivity networks, and this approach provides insight into network-level regional recruitment. In this fMRI study, three complementary, but distinct ToM tasks assessing mental state detection (e.g. RMIE: Reading the Mind in the Eyes; RMIV: Reading the Mind in the Voice) and intentional attribution (Causality task) were each analyzed using ICA in order to separately characterize the recruitment and functional connectivity of core nodes in the ToM network in response to the sub-processes of ToM. Based on visual comparison of the derived networks for each task, the spatiotemporal network patterns were similar between the RMIE and RMIV tasks, which elicited mentalizing about the mental states of others, and these networks differed from the network derived for the Causality task, which elicited mentalizing about goal-directed actions. The medial prefrontal cortex, precuneus, and right inferior frontal gyrus were seen in the components with the highest correlation with the task condition for each of the tasks highlighting the role of these regions in general ToM processing. Using a data-driven approach, the current study captured the differences in task-related brain response to ToM in three distinct ToM paradigms. The findings of this study further elucidate the neural mechanisms associated with mental state detection and causal attribution, which represent possible sub-processes of the complex construct of ToM processing. [ABSTRACT FROM AUTHOR]

Most of the existing behavioral and cognitive intervention programs in autism spectrum disorders (ASD) have not been tested at the neurobiological level, thus falling short of finding quantifiable neurobiological changes underlying behavioral improvement. The current study takes a translational neuroimaging approach to test the impact of a structured visual imagery-based reading intervention on improving reading comprehension and assessing its underlying local neural circuitry. Behavioral and resting state functional MRI (rs-fMRI) data were collected from children with ASD who were randomly assigned to an Experimental group (ASD-EXP; n = 14) and a Wait-list control group (ASD-WLC; n = 14). Participants went through an established reading intervention training program (Visualizing and Verbalizing for language comprehension and thinking or V/V; 4-h per day, 10-weeks, 200 h of face-to-face instruction). Local functional connectivity was examined using a connection density approach from graph theory focusing on brain areas considered part of the Reading Network. The main results are as follows: (I) the ASD-EXP group showed significant improvement, compared to the ASD-WLC group, in their reading comprehension ability evidenced from change in comprehension scores; (II) the ASD-EXP group showed increased local brain connectivity in Reading Network regions compared to the ASD-WLC group post-intervention; (III) intervention-related changes in local brain connectivity were observed in the ASD-EXP from pre to post-intervention; and (IV) improvement in language comprehension significantly predicted changes in local connectivity. The findings of this study provide novel insights into brain plasticity in children with developmental disorders using targeted intervention programs. [ABSTRACT FROM AUTHOR]

This study systematically reviewed the literature on reading interventions for autistic children. Peer-reviewed articles that reported behavioral and/or neurobiological effects of reading intervention were identified in five online databases. After screening, 15 studies met the inclusion criteria for this review. These studies focus on interventions targeted towards improving specific reading skills: comprehension, vocabulary, fluency, and phonological awareness. Studied interventions included interactive and shared reading, visualization strategies, vocabulary and main idea instruction, video modeling, and interventions supported by tablet-based technology. Overall, the studies identified in this review reported improvements to each of the targeted reading skills and changes to neural activation and connectivity. In addition, changes at the brain level were associated with improvements in reading. Specifically, frontal, temporal, and occipital regions associated with visual and language processing showed increased activation and functional connectivity following intervention. This review provides important insights into the landscape of reading intervention studies in autism and into the neurobiological underpinnings of reading skills and how interventions affect those processes. • Studies report that interventions improve the reading skills of autistic children. • Reading comprehension, vocabulary, fluency, and phonological awareness improved. • Neuroimaging studies showed increased cortical activation and connectivity. • Brain changes directly related to improvement in reading comprehension. [ABSTRACT FROM AUTHOR]

• This study examined corpus callosum size and interhemispheric connectivity in autism. • Central subregion of callosum was smaller in participants with autism. • Poor social skills were negatively correlated with central subregion volume. • Participants with autism showed stronger homotopic functional connectivity. • Study provides new evidence of brain structure-function relationship in autism. By examining how morphology of the corpus callosum (CC) in autism spectrum disorder (ASD) may affect functional communication across hemispheres, we hope to provide new insights into the structure-function relationship in the brain. We used a sample of 94 participants from the Autism Brain Imaging Data Exchange (ABIDE) database (55 typically-developing (TD) and 39 with ASD). The CC was segmented into five sub-regions (anterior, mid-anterior, central, mid-posterior, posterior) using FreeSurfer software, which were further examined for group differences. The total volume and specific sub-region volumes of the CC, and interhemispheric (homotopic) functional connectivity were calculated, along with the relationship between volume and connectivity. These measures were correlated with social ability assessed by the Social Responsiveness Scale (SRS). The central sub-region of CC was significantly smaller in ASD, although there was no group difference in total CC volume. ASD participants also showed stronger homotopic connectivity in the superior frontal gyrus. SRS scores were negatively correlated with the CC central sub-region volumes in ASD. The findings of this study add to the body of research showing morphological differences in the CC in ASD as well as connectivity differences. The absence of a significant relationship between structure and homotopic functional connectivity aligns with previous findings. [ABSTRACT FROM AUTHOR]

Deficits in social communication in autism spectrum disorder (ASD) have been documented using neuroimaging techniques such as functional MRI over the past decade. More recently, functional connectivity MRI has revealed altered connectivity in face processing, mentalizing, and mirroring brain networks, networks involved in the social brain in ASD. However, to our knowledge, previous studies have not examined these three networks concurrently. The purpose of the current study was to investigate the functional connectivity of the face processing, mentalizing, and mirroring networks (within each network and across networks) in ASD during an action-intention task in which participants were asked to determine the means and intention of a model's actions. We examined: a) within-network connectivity of each network using an ROI-to-ROI analysis; b) connectivity of each network hub to the rest of the brain using a seed-to-voxel analysis; c) the between-network connectivity of each network hub using ROI-to-ROI analysis; and d) brain-behavior relationships by correlating autism symptoms with brain connectivity. Task-fMRI data were used from 21 participants with ASD and 20 typically developing participants. The ASD group consistently showed significantly greater connectivity between networks and between hub regions to the rest of the brain. Hyperconnectivity in ASD may entail more and widespread resource utilization for accomplishing action-intention judgment. • This fMRI study examined action-intention judgment in individuals with autism. • Three brain networks were examined: face processing, mentalizing, and mirroring. • Autism group showed hyperconnectivity in connectivity of different hubs. • Connectivity was found to be correlated with autism symptomology. [ABSTRACT FROM AUTHOR]

One of the earliest neurobiological findings in autism has been the differences in the thalamocortical pathway connectivity, suggesting the vital role thalamus plays in human experience. The present functional MRI study investigated resting-state functional connectivity of the thalamus in 49 (autistic, ADHD, and neurotypical) young adults. All participants underwent structural MRI and eyes-open resting state functional MRI scans. After preprocessing the imaging data using Conn's connectivity toolbox, a seed-based functional connectivity analysis was conducted using bilateral thalamus as primary seeds. Autistic participants showed stronger thalamic connectivity, relative to ADHD and neurotypical participants, between the right thalamus and right precentral gyrus, right pars opercularis-BA44, right postcentral gyrus, and the right superior parietal lobule (RSPL). Autistic participants also showed significantly increased connectivity between the left thalamus and the right precentral gyrus. Furthermore, regression analyses revealed a significant relationship between autistic traits and left thalamic-precentral connectivity (R 2  = 0.1113), as well as between autistic traits and right postcentral gyrus and RSPL connectivity (R 2  = 0.1204) in autistic participants compared to ADHD. These findings provide significant insights into the role of thalamus in coordinating neural information processing and its alterations in neurodevelopmental disorders., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2023 Karavallil Achuthan, Stavrinos, Argueta, Vanderburgh, Holm and Kana.)

Background: Autism and attention-deficit/hyperactivity disorder (ADHD) are comorbid neurodevelopmental disorders that share common and distinct neurobiological mechanisms, with disrupted brain connectivity patterns being a hallmark feature of both conditions. It is challenging to gain a mechanistic understanding of the underlying disorder, because brain connectivity changes in autism and ADHD are heterogeneous. Objectives: The present resting state functional MRI (rs-fMRI) study focuses on investigating the shared and distinct resting state-fMRI connectivity (rsFC) patterns in autistic and ADHD adults using multi-voxel pattern analysis (MVPA). By identifying spatial patterns of fMRI activity across a given time course, MVPA is an innovative and powerful method for generating seed regions of interest (ROIs) without a priori hypotheses. Methods: We performed a data-driven, whole-brain, connectome-wide MVPA on rs-fMRI data collected from 15 autistic, 19 ADHD, and 15 neurotypical (NT) young adults. Results: MVPA identified cerebellar vermis 9, precuneus, and the right cerebellum VI for autistic versus NT, right inferior frontal gyrus and vermis 9 for ADHD versus NT, and right dorsolateral prefrontal cortex for autistic versus ADHD as significant clusters. Post hoc seed-to-voxel analyses using these clusters as seed ROIs were performed for further characterization of group differences. The cerebellum VI, vermis, and precuneus in autistic adults, and the vermis and frontal regions in ADHD showed different connectivity patterns in comparison with NT. Conclusions: The study characterizes the rsFC profile of cerebellum with key cortical areas in autism and ADHD, and it emphasizes the importance of studying the role of the functional connectivity of the cerebellum in neurodevelopmental disorders.

Resting state fMRI (rs-fMRI) provides an excellent platform for examining the amplitude of low frequency fluctuations (ALFF) and fractional amplitude of low frequency fluctuations (fALFF), which are key indices of brain functioning. However, ALFF and fALFF have been used only sporadically to study autism. rs-fMRI data from 69 children (40 autistic, mean age = 8.47 ± 2.20 years; age range: 5.2 to 13.2; and 29 non-autistic, mean age = 9.02 ± 1.97 years; age range 5.9 to 12.9) were obtained from the Autism Brain Imaging Data Exchange (ABIDE II). ALFF and fALFF were measured using CONN connectivity toolbox and SPM12, at whole-brain & network-levels. A two-sampled t-test and a 2 Group (autistic, non-autistic) × 7 Networks ANOVA were conducted to test group differences in ALFF and fALFF. The whole-brain analysis identified significantly reduced ALFF values for autistic participants in left parietal opercular cortex, precuneus, and right insula. At the network level, there was a significant effect of diagnostic group and brain network on ALFF values, and only significant effect of network, not group, on fALFF values. Regression analyses indicated a significant effect of age on ALFF values of certain networks in autistic participants. Such intrinsically different network-level responses in autistic participants may have implications for task-level recruitment and synchronization of brain areas, which may in turn impact optimal cognitive functioning. Moreover, differences in low frequency fluctuations of key networks, such as the DMN and SN, may underlie alterations in brain responses in autism that are frequently reported in the literature., (© 2022 International Society for Autism Research and Wiley Periodicals LLC.)

Drivers with neurodevelopmental disorders (NDDs), such as autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are at increased risk of experiencing driving difficulties. An important aspect of driving safety and skill involves hazard detection. This functional magnetic resonance imaging study examined the neural responses associated with driving hazard detection in drivers with ASD, ADHD, and typically developing (TD) drivers. Forty participants (12 ASD, 15 ADHD, 13 TD) ages 16-30 years completed a driving simulator task in which they encountered social and nonsocial hazards; reaction time (RT) for responding to hazards was measured. Participants then completed a similar hazard detection task in the MRI scanner so that neural response to hazards could be measured. Activation of regions of interest considered part of the executive function (EF) and theory of mind (ToM) networks were examined and related to driving simulator behavior. Results showed that stronger activation of the EF network during social hazard processing, including the bilateral dorsolateral prefrontal cortex and posterior parietal cortex, was associated with faster RT to social hazards among drivers with ADHD, but not among drivers with ASD. This provides the first evidence of a relationship between EF network brain activation and driving skills in ADHD and suggests that alterations in this network may underlie driving behavior. In comparison, the current study did not observe a relationship between ToM network activation and RT to social hazards in any group. This study lays the groundwork for relating neural activation to driving behavior among individuals with NDDs., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Despite decades of research, the brain basis of aberrant face processing in autism spectrum disorder (ASD) remains a topic of debate. The mid-fusiform sulcus (MFS), a minor feature of the ventral occipitotemporal cortex, provides new directions for studying face processing. The MFS closely aligns with face-selective cortical patches and other structural and functional divisions of the fusiform gyrus; however, it has received little attention in clinical populations. We collected structural MRI data from 54 individuals with ASD and 61 age-and-IQ-matched controls ages 8 to 40 years. The MFS was identified on cortical surface reconstructions via 4 trained raters and classified into known surface patterns. Mean MFS gray matter volume (GMV), cortical surface area (SA), cortical thickness (CT), and standard deviation of CT (CT SD) were extracted. Effects of diagnosis, age, and hemisphere on MFS surface presentation and morphometry were assessed via multinomial logistic regression and mixed effects general linear modeling, respectively. The MFS was reliably identified in 97% of hemispheres examined. Macroanatomical patterns and age-related decreases in MFS GMV and CT were similar between groups. CT SD was greater in the left hemisphere in ASD. Participants' ability to interpret emotions and mental states from facial features was significantly negatively correlated with MFS CT and CT SD. Overall, the MFS is a stable feature of the fusiform gyrus in ASD and CT related measures appear to be sensitive to diagnosis and behavior. These results can inform future investigations of face processing and structure-function relationships in populations with social deficits. LAY SUMMARY: A small structural feature of the brain related to seeing faces (the mid-fusiform sulcus; MFS) appears similar in autism spectrum disorder (ASD) and neurotypical development; however, the thickness of this structure on the left side of the brain is more variable in ASD. People who are better at judging mental states from another person's eyes tend to have thinner and less variable MFS. This feature may teach us more about face processing and how brain structure influences function in ASD., (© 2020 International Society for Autism Research and Wiley Periodicals LLC.)

There is growing evidence of altered connectivity in autism spectrum disorders (ASD) between the cerebellum and cortex. Three intrinsic connectivity networks (ICNs) are especially important to cognitive processing in ASD: the default mode network (DMN), executive control network (ECN), and salience networks (SNs). The goal of this study was to compare resting-state functional connectivity between the cerebellum and the DMN, ECN, and SN in ASD and typically developing children (n = 74, ages 7-12 years). Children with ASD showed stronger connectivity between the ventral DMN and left cerebellar lobules I-IV. No meaningful relationships were observed between ICN-cerebellar functional connectivity and ASD symptoms. These results suggest that the cerebellum contributes to altered network connectivity in ASD.

Recent years have witnessed the proliferation of neuroimaging studies of neurodevelopmental disorders (NDDs), particularly of children with autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), and Tourette's syndrome (TS). Neuroimaging offers immense potential in understanding the biology of these disorders, and how it relates to clinical symptoms. Neuroimaging techniques, in the long run, may help identify neurobiological markers to assist clinical diagnosis and treatment. However, methodological challenges have affected the progress of clinical neuroimaging. This paper reviews the methodological challenges involved in imaging children with NDDs. Specific topics include correcting for head motion, normalization using pediatric brain templates, accounting for psychotropic medication use, delineating complex developmental trajectories, and overcoming smaller sample sizes. The potential of neuroimaging-based biomarkers and the utility of implementing neuroimaging in a clinical setting are also discussed. Data-sharing approaches, technological advances, and an increase in the number of longitudinal, prospective studies are recommended as future directions. Significant advances have been made already, and future decades will continue to see innovative progress in neuroimaging research endeavors of NDDs., (Published by Elsevier Ltd.)

Neuroimaging studies have uncovered structural and functional alterations in the cingulate cortex in individuals with autism spectrum disorders (ASD). Such abnormalities may underlie neurochemical imbalance. In order to characterize the neurochemical profile, the current study examined the concentration of brain metabolites in dorsal ACC (dACC) and posterior cingulate cortex (PCC) in high-functioning adults with ASD. Twenty high-functioning adults with ASD and 20 age-and-IQ-matched typically developing (TD) peers participated in this Proton magnetic resonance spectroscopy (1H-MRS) study. LCModel was used in analyzing the spectra to measure the levels of N-Acetyl aspartate (NAA), choline (Cho), creatine (Cr), and glutamate/glutamine (Glx) in dACC and PCC. Groups were compared using means for the ratio of each metabolite to their respective Cr levels as well as on absolute internal-water-referenced measures of each metabolite. There was a significant increase in Cho in PCC for ASD adults, with a marginal increase in dACC. A reduction in NAA/Cr in dACC was found in ASD participants, compared to their TD peers. No significant differences in Glx/Cr or Cho/Cr were found in dACC. There were no statistically significant group differences in the absolute concentration of NAA, Cr, Glx, or NAA/Cr, Cho/Cr, and Glx/Cr in the PCC. Differences in the metabolic properties of dACC compared to PCC were also found. Results of this study provide evidence for possible cellular and metabolic differences in the dACC and PCC in adults with ASD. This may suggest neuronal dysfunction in these regions and may contribute to the neuropathology of ASD. Autism Res 2016, 9: 643-657. © 2015 International Society for Autism Research, Wiley Periodicals, Inc., (© 2015 International Society for Autism Research, Wiley Periodicals, Inc.)

Interpreting emotional expressions appropriately poses a challenge for individuals with autism spectrum disorder (ASD). In particular, difficulties with emotional processing in ASD are more pronounced in contexts where emotional expressions are subtle, automatic, and reflexive-that is, implicit. In contrast, explicit emotional processing, which requires the cognitive evaluation of an emotional experience, appears to be relatively intact in individuals with ASD. In the present study, we examined the brain activation and functional connectivity differences underlying explicit and implicit emotional processing in age- and IQ-matched adults with (n = 17) and without (n = 15) ASD. Results indicated: (1) significantly reduced levels of brain activation in participants with ASD in medial prefrontal cortex (MPFC) and superior temporal gyrus (STG) during implicit emotion processing; (2) significantly weaker functional connectivity in the ASD group in connections of the MPFC with the amygdala, temporal lobe, parietal lobe, and fusiform gyrus; (3) No group difference in performance accuracy or reaction time; and (4) Significant positive relationship between empathizing ability and STG activity in ASD but not in typically developing participants. These findings suggest that the neural mechanisms underlying implicit, but not explicit, emotion processing may be altered at multiple levels in individuals with ASD., (© 2015 International Society for Autism Research, Wiley Periodicals, Inc.)

Deficits in language comprehension have been widely reported in children with autism spectrum disorders (ASD), with behavioral and neuroimaging studies finding increased reliance on visuospatial processing to aid in language comprehension. However, no study to date, has taken advantage of this strength in visuospatial processing to improve language comprehension difficulties in ASD. This study used a translational neuroimaging approach to test the role of a visual imagery-based reading intervention in improving the brain circuitry underlying language processing in children with ASD. Functional magnetic resonance imaging (MRI), in a longitudinal study design, was used to investigate intervention-related change in sentence comprehension, brain activation, and functional connectivity in three groups of participants (age 8-13 years): an experimental group of ASD children (ASD-EXP), a wait-list control group of ASD children (ASD-WLC), and a group of typically developing control children. After intervention, the ASD-EXP group showed significant increase in activity in visual and language areas and right-hemisphere language area homologues, putamen, and thalamus, suggestive of compensatory routes to increase proficiency in reading comprehension. Additionally, ASD children who had the most improvement in reading comprehension after intervention showed greater functional connectivity between left-hemisphere language areas, the middle temporal gyrus and inferior frontal gyrus while reading high imagery sentences. Thus, the findings of this study, which support the principles of dual coding theory [Paivio 2007], suggest the potential of a strength-based reading intervention in changing brain responses and facilitating better reading comprehension in ASD children., (© 2015 International Society for Autism Research, Wiley Periodicals, Inc.)

Motor-linked implicit learning is the learning of a sequence of movements without conscious awareness. Although motor symptoms are frequently reported in individuals with autism spectrum disorder (ASD), recent behavioral studies have suggested that motor-linked implicit learning may be intact in ASD. The serial reaction time (SRT) task is one of the most common measures of motor-linked implicit learning. The present study used a 3T functional magnetic resonance imaging scanner to examine the behavioral and neural correlates of real-time motor sequence learning in adolescents and adults with ASD (n = 15) compared with age- and intelligence quotient-matched individuals with typical development (n = 15) during an SRT task. Behavioral results suggested less robust motor sequence learning in individuals with ASD. Group differences in brain activation suggested that individuals with ASD, relative to individuals with typical development, showed decreased activation in the right superior parietal lobule (SPL) and right precuneus (Brodmann areas 5 and 7, and extending into the intraparietal sulcus) during learning. Activation in these areas (and in areas such as the right putamen and right supramarginal gyrus) was found to be significantly related to behavioral learning in this task. Additionally, individuals with ASD who had more severe repetitive behavior/restricted interest symptoms demonstrated greater decreased activation in these regions during motor learning. In conjunction, these results suggest that the SPL may play an important role in motor learning and repetitive behavior in individuals with ASD., (© 2014 International Society for Autism Research, Wiley Periodicals, Inc.)

Autism spectrum disorders (ASD) are characterized by impairments in social communication and restrictive, repetitive behaviors. While behavioral symptoms are well-documented, investigations into the neurobiological underpinnings of ASD have not resulted in firm biomarkers. Variability in findings across structural neuroimaging studies has contributed to difficulty in reliably characterizing the brain morphology of individuals with ASD. These inconsistencies may also arise from the heterogeneity of ASD, and wider age-range of participants included in MRI studies and in previous meta-analyses. To address this, the current study used coordinate-based anatomical likelihood estimation (ALE) analysis of 21 voxel-based morphometry (VBM) studies examining high-functioning individuals with ASD, resulting in a meta-analysis of 1055 participants (506 ASD, and 549 typically developing individuals). Results consisted of grey, white, and global differences in cortical matter between the groups. Modeled anatomical maps consisting of concentration, thickness, and volume metrics of grey and white matter revealed clusters suggesting age-related decreases in grey and white matter in parietal and inferior temporal regions of the brain in ASD, and age-related increases in grey matter in frontal and anterior-temporal regions. White matter alterations included fiber tracts thought to play key roles in information processing and sensory integration. Many current theories of pathobiology ASD suggest that the brains of individuals with ASD may have less-functional long-range (anterior-to-posterior) connections. Our findings of decreased cortical matter in parietal-temporal and occipital regions, and thickening in frontal cortices in older adults with ASD may entail altered cortical anatomy, and neurodevelopmental adaptations.

Visual information is processed in the brain primarily through two distinct pathways, the dorsal and the ventral visual streams. The present functional magnetic resonance imaging study investigated the specialization and integration of dorsal and ventral streams using tasks of object recognition and location detection. The study included 22 healthy adult volunteers who viewed stimuli consisting of grayscale photographs of common household objects presented in blocked design. Participants were asked to either recognize an object or to locate its position. While the location detection task elicited greater activation in the dorsal visual stream, recognizing objects showed greater activation in the middle occipital gyri, left inferior temporal gyrus, and in the left inferior frontal gyrus. The integration between dorsal and ventral brain areas was stronger during location detection than during object recognition. In addition, a principal components analysis found preliminary evidence for a group of regions, such as frontal and parietal cortex, working together in this task. Overall, the results of this study indicate the existence of specialized modules for object recognition and location detection, and possible interactions between areas beyond the visual cortex that may play a role in such tasks.