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Auditory-musical processing in autism spectrum disorders: a review of behavioral and brain imaging studies

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition characterized by atypical social and communication skills, repetitive behaviors, and atypical visual and auditory perception. Studies in vision have reported enhanced detailed (“local”) processing but diminished holistic (“global”) processing of visual features in ASD. Individuals with ASD also show enhanced processing of simple visual stimuli but diminished processing of complex visual stimuli. Relative to the visual domain, auditory global–local distinctions, and the effects of stimulus complexity on auditory processing in ASD, are less clear. However, one remarkable finding is that many individuals with ASD have enhanced musical abilities, such as superior pitch processing. This review provides a critical evaluation of behavioral and brain imaging studies of auditory processing with respect to current theories in ASD. We have focused on auditory‐musical processing in terms of global versus local processing and simple versus complex sound processing. This review contributes to a better understanding of auditory processing differences in ASD. A deeper comprehension of sensory perception in ASD is key to better defining ASD phenotypes and, in turn, may lead to better interventions.

Atypical Functional Brain Connectivity during Rest in Autism Spectrum Disorders

Connectivity atypicalities in autism spectrum disorders (ASD) have been extensively proposed. The default mode network (DMN) is critical in this study, given the insight it provides for long‐distance connectivity, and the importance of regions in this network for introspection and social emotion processing, areas affected in ASD. However, study of this network has largely been limited to adults; research earlier in development is lacking. The objective of this study was to examine DMN connectivity in children/adolescents with ASD.

Developing the Medical Liaison Role in School Settings

There is a reciprocal relationship between medical and educational systems; nearly all medical issues for children have educational ramifications and educational settings are ideal for implementing preventative and ameliorative medical strategies. Systemic models of collaboration between medical and educational systems are necessary but not sufficient for effective collaboration. Individual professionals with expertise in medical issues, educational issues, and collaborative skills are required to achieve productive collaboration across medical and educational systems. This article describes the transdisciplinary role of the medical liaison required to overcome the pragmatic and systemic obstacles to effective collaboration between medical and educational systems.

Language Ability Predicts Cortical Structure and Covariance in Boys with Autism Spectrum Disorder

Abstract There is significant clinical heterogeneity in language and communication abilities of individuals with Autism Spectrum Disorders (ASD). However, no consistent pathology regarding the relationship of these abilities to brain structure has emerged. Recent developments in anatomical correlation‐based approaches to map structural covariance networks (SCNs), combined with detailed behavioral characterization, offer an alternative for studying these relationships. In this study, such an approach was used to study the integrity of SCNs of cortical thickness and surface area associated with language and communication, in 46 high‐functioning, school‐age children with ASD compared with 50 matched, typically developing controls (all males) with IQ > 75. Findings showed that there was alteration of cortical structure and disruption of fronto‐temporal cortical covariance in ASD compared with controls. Furthermore, in an analysis of a subset of ASD participants, alterations in both cortical structure and covariance were modulated by structural language ability of the participants, but not communicative function. These findings indicate that structural language abilities are related to altered fronto‐temporal cortical covariance in ASD, much more than symptom severity or cognitive ability. They also support the importance of better characterizing ASD samples while studying brain structure and for better understanding individual differences in language and communication abilities in ASD.

Effects of Age and Attention on Auditory Global-Local Processing in Children with Autism Spectrum Disorder.

Abstract In vision, typically-developing (TD) individuals perceive “global” (whole) before “local” (detailed) features, whereas individuals with autism spectrum disorder (ASD) exhibit a local bias. However, auditory global–local distinctions are less clear in ASD, particularly in terms of age and attention effects. To these aims, here ASD and TD children judged local and global pitch structure in nine-tone melodies. Both groups showed a similar global precedence effect, but ASD children were less sensitive to global interference than TD children at younger ages. There was no effect of attention task. These findings provide novel evidence of developmental differences in auditory perception and may help to refine sensory phenotypes in ASD.

Atypical thalamo-cortical resting-state connectivity is correlated with repetitive behaviours in autism spectrum disorder

these truncating mutations in DOCK7. These mutations have not been observed in public SNP databases and are predicted to abolish critical domains for DOCK7 function. DOCK7 codes for a Rac guanine nucleotide exchange factor that has been implicated in the genesis and polarization of newborn pyramidal neurons as well as in the morphological differentiation of GABAergic interneurons in the developing cortex. All together, these observations suggest that loss of DOCK7 function causes a previously unrecognized syndrome by affecting multiple neuronal processes.

Auditory cortical structure predicts superior pitch processing in children with autism

indicated a reappearance of the myelinated cortical fibers. However, these new fibers lacked directionality observed in the control brains. The analysis of Ki67 antigen, known to be associated with proliferating cells, showed increased number of proliferating cells in the subventricular Zone (SVZ) of the STB mice which followed by a reduction in the LTB mice. We observed blast-induced migration of immature Olig2 expressing oligodendrocytes through the corpus callosum and increased number of Olig2+ cells in the cingulate cortex of LTB mice. Immunostaining for an early neuronal cell marker, Doublecortin, suggests a transient blast-induced increase in the number of neuronal progenitors in the SVZ. The results suggest that the increase in blast-induced activation of the brain neural stem/progenitor cells generates predominantly new oligodendrocytes. This work was supported by NYSTEM contracts C026415 and C026714.

Neuroanatomical correlates of auditory-motor synchronization in children with autism

The investigation was carried out to evaluate alterations in histoarchitecture, oxidative stress parameter (lipid peroxidation, LPx) and antioxidant enzyme activities in cerebral cortex of rat brain in response to 6-n-propyl 2-thiouracil (PTU)-induced hypothyroidism during postnatal development (from birth to 7, 15 and 30 days old). Hypothyroidism in rats was induced by feeding the lactating mothers (from the day of parturition till weaning, 25 days old) or directly to the pups with 0.05% PTU in drinking water. A significant decrease in level of LPx was seen in 7 and 30 days old PTU-treated rats with respect to their controls. Significantly decreased activities of superoxide dismutase (SOD) and catalase (CAT) along with the translated products of SOD1 and SOD2 were observed in 7, 15 and 30 days old PTU-treated rats as compared to their respective controls. However, increase in translated product of CAT was seen in all age groups of PTU-treated rats. Histological sections of 30 days hypothyroid rats clearly exhibited a decline in neuronal migration with neurons packed together in the hypothyroid group as compared to the control. These results suggest that deprivation of thyroid hormone modulates antioxidant defence status as well as the histoarchitecture of rat brain cerebral cortex during postnatal development.