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Patients with autism spectrum disorders (ASDs) may have difficulty tolerating conventional dental treatment due to aberrant sensory responsiveness. The purpose of this report was to describe the successful treatment of obstructive sleep apnea (OSA) in a nonverbal 20-year-old male patient with ASD using a dental appliance. A series of appointments prepared the patient for the required treatment procedures and desensitized him for use of the final appliance. The final appliance improved outcomes of a post-treatment sleep study, indicating successful treatment of OSA. Understanding the specific challenges of patients with ASD and the patience and foresight of providers in approaching these challenges, in collaboration with caregivers, can contribute to improved health outcomes for these patients.
Autism spectrum disorder (ASD) has been associated with various sensory atypicalities across multiple domains. Interoception, the ability to detect and attend to internal bodily sensations, has been found to moderate the experience of body ownership, a known difference in ASD that may affect social function. However, interoception has not been empirically examined in ASD. In the current study, 45 children (21 with ASD and 24 controls) ages 8 to 17 years completed a heartbeat perception paradigm as a measure of interoceptive ability. A subset of these children also completed the rubber hand illusion task, a multisensory paradigm probing the malleability of perceived body ownership. Although the heartbeat perception paradigm yielded comparable interoceptive awareness (IA) overall across both groups, children with ASD were superior at mentally tracking their heartbeats over longer intervals, suggesting increased sustained attention to internal cues in ASD. In addition, IA was negatively correlated with rubber hand illusion susceptibility in both groups, supporting a previously demonstrated inverse relationship between internal awareness and one's ability to incorporate external stimuli into one's perception of self. We propose a trade-off between attention to internal cues and attention to external cues, whereby attentional resources are disproportionately allocated to internal, rather than external, sensory cues in ASD.
Copyright © 2014 Elsevier Inc. All rights reserved.
Autism spectrum disorder (ASD) has been characterized by atypical socio-communicative behavior, sensorimotor impairment and abnormal neurodevelopmental trajectories. DTI has been used to determine the presence and nature of abnormality in white matter integrity that may contribute to the behavioral phenomena that characterize ASD. Although atypical patterns of sensory responding in ASD are well documented in the behavioral literature, much less is known about the neural networks associated with aberrant sensory processing. To address the roles of basic sensory, sensory association and early attentional processes in sensory responsiveness in ASD, our investigation focused on five white matter fiber tracts known to be involved in these various stages of sensory processing: superior corona radiata, centrum semiovale, inferior longitudinal fasciculus, posterior limb of the internal capsule, and splenium. We acquired high angular resolution diffusion images from 32 children with ASD and 26 typically developing children between the ages of 5 and 8. We also administered sensory assessments to examine brain-behavior relationships between white matter integrity and sensory variables. Our findings suggest a modulatory role of the inferior longitudinal fasciculus and splenium in atypical sensorimotor and early attention processes in ASD. Increased tactile defensiveness was found to be related to reduced fractional anisotropy in the inferior longitudinal fasciculus, which may reflect an aberrant connection between limbic structures in the temporal lobe and the inferior parietal cortex. Our findings also corroborate the modulatory role of the splenium in attentional orienting, but suggest the possibility of a more diffuse or separable network for social orienting in ASD. Future investigation should consider the use of whole brain analyses for a more robust assessment of white matter microstructure.
Sleep disruption is common in individuals with autism spectrum disorder (ASD). Genes whose products regulate endogenous melatonin modify sleep patterns and have been implicated in ASD. Genetic factors likely contribute to comorbid expression of sleep disorders in ASD. We studied a clinically unique ASD subgroup, consisting solely of children with comorbid expression of sleep onset delay. We evaluated variation in two melatonin pathway genes, acetylserotonin O-methyltransferase (ASMT) and cytochrome P450 1A2 (CYP1A2). We observed higher frequencies than currently reported (p < 0.04) for variants evidenced to decrease ASMT expression and related to decreased CYP1A2 enzyme activity (p ≤ 0.0007). We detected a relationship between genotypes in ASMT and CYP1A2 (r(2) = 0.63). Our results indicate that expression of sleep onset delay relates to melatonin pathway genes.
Individuals with autism spectrum disorders (ASD) exhibit alterations in sensory processing, including changes in the integration of information across the different sensory modalities. In the current study, we used the sound-induced flash illusion to assess multisensory integration in children with ASD and typically-developing (TD) controls. Thirty-one children with ASD and 31 age and IQ matched TD children (average age = 12 years) were presented with simple visual (i.e., flash) and auditory (i.e., beep) stimuli of varying number. In illusory conditions, a single flash was presented with 2-4 beeps. In TD children, these conditions generally result in the perception of multiple flashes, implying a perceptual fusion across vision and audition. In the present study, children with ASD were significantly less likely to perceive the illusion relative to TD controls, suggesting that multisensory integration and cross-modal binding may be weaker in some children with ASD. These results are discussed in the context of previous findings for multisensory integration in ASD and future directions for research.
The new DSM-5 diagnostic criteria for autism spectrum disorders (ASDs) include sensory disturbances in addition to the well-established language, communication, and social deficits. One sensory disturbance seen in ASD is an impaired ability to integrate multisensory information into a unified percept. This may arise from an underlying impairment in which individuals with ASD have difficulty perceiving the temporal relationship between cross-modal inputs, an important cue for multisensory integration. Such impairments in multisensory processing may cascade into higher-level deficits, impairing day-to-day functioning on tasks, such as speech perception. To investigate multisensory temporal processing deficits in ASD and their links to speech processing, the current study mapped performance on a number of multisensory temporal tasks (with both simple and complex stimuli) onto the ability of individuals with ASD to perceptually bind audiovisual speech signals. High-functioning children with ASD were compared with a group of typically developing children. Performance on the multisensory temporal tasks varied with stimulus complexity for both groups; less precise temporal processing was observed with increasing stimulus complexity. Notably, individuals with ASD showed a speech-specific deficit in multisensory temporal processing. Most importantly, the strength of perceptual binding of audiovisual speech observed in individuals with ASD was strongly related to their low-level multisensory temporal processing abilities. Collectively, the results represent the first to illustrate links between multisensory temporal function and speech processing in ASD, strongly suggesting that deficits in low-level sensory processing may cascade into higher-order domains, such as language and communication.
BACKGROUND - Children with autism spectrum disorder (ASD) are impaired in social communication and interaction with peers, which may reflect diminished social motivation. Many children with ASD show enhanced stress when playing with other children. This study investigated social and stress profiles of children with ASD during play.
METHODS - We utilized a peer interaction paradigm in a natural playground setting with 66 unmedicated, prepubertal, children aged 8-12 years [38 with ASD, 28 with typical development (TD)]. Salivary cortisol was collected before and after a 20-min playground interaction that was divided into periods of free and solicited play facilitated by a confederate child. Statistical analyses included Wilcoxon rank-sum tests, mixed effects models, and Spearman correlations to assess the between-group differences in social and stress functioning, identify stress responders, and explore associations between variables, respectively.
RESULTS - There were no differences between the groups during unsolicited free play; however, during solicited play by the confederate, significant differences emerged such that children with ASD engaged in fewer verbal interactions and more self-play than the TD group. Regarding physiological arousal, children with ASD as a group showed relatively higher cortisol in response to social play; however, there was a broad range of responses. Moreover, those with the highest cortisol levels engaged in less social communication.
CONCLUSIONS - The social interaction of children with ASD can be facilitated by peer solicitation; however, it may be accompanied by increased stress. The children with ASD that have the highest level of cortisol show less social motivation; yet, it is unclear if it reflects an underlying state of heightened arousal or enhanced reactivity to social engagement, or both.
© 2013 The Authors. Journal of Child Psychology and Psychiatry © 2013 Association for Child and Adolescent Mental Health.
Atypical communicative abilities are a core marker of Autism Spectrum Disorders (ASD). A number of studies have shown that, in addition to auditory comprehension differences, individuals with autism frequently show atypical responses to audiovisual speech, suggesting a multisensory contribution to these communicative differences from their typically developing peers. To shed light on possible differences in the maturation of audiovisual speech integration, we tested younger (ages 6-12) and older (ages 13-18) children with and without ASD on a task indexing such multisensory integration. To do this, we used the McGurk effect, in which the pairing of incongruent auditory and visual speech tokens typically results in the perception of a fused percept distinct from the auditory and visual signals, indicative of active integration of the two channels conveying speech information. Whereas little difference was seen in audiovisual speech processing (i.e., reports of McGurk fusion) between the younger ASD and TD groups, there was a significant difference at the older ages. While TD controls exhibited an increased rate of fusion (i.e., integration) with age, children with ASD failed to show this increase. These data suggest arrested development of audiovisual speech integration in ASD. The results are discussed in light of the extant literature and necessary next steps in research.