James W. Bodfish

DSM-5 Changes and the Prevalence of Parent-Reported Autism Spectrum Symptoms in Fragile X Syndrome.

We used survey methodology to assess parent-reported autism symptomology in 758 individuals (639 males; 119 females) with fragile X syndrome (FXS). Caregivers reported whether their child with FXS had been diagnosed with an autism spectrum disorder (ASD) and endorsed symptoms based on a list of observable behaviors related to ASD diagnoses. Symptom counts were categorized based on DSM-IV-TR and DSM-5 criteria. Based on behavioral symptoms endorsed by caregivers, 38.7xa0% of males and 24.7xa0% of females met criteria for DSM-IV-TR diagnosis of autistic disorder. Significantly fewer males (27.8xa0%) and females (11.3xa0%) met criteria for ASD based on DSM-5 criteria. Although 86.4xa0% of males and 61.7xa0% of females met criteria for the restricted and repetitive behavior domain for DSM-5, only 29.4xa0% of males and 13.0xa0% of females met criteria for the social communication and interaction (SCI) domain. Relaxing the social communication criteria by one symptom count led to a threefold increase in those meeting criteria for ASD, suggesting the importance of subthreshold SCI symptoms for individuals with FXS in ASD diagnoses. Findings suggest important differences in the way ASD may be conceptualized in FXS based on the new DSM-5 criteria.

Functional neuroimaging of social and nonsocial cognitive control in autism

This study investigated cognitive control of social and nonsocial information in autism using functional magnetic resonance imaging. Individuals with autism spectrum disorders (ASDs) and a neurotypical control group completed an oddball target detection task where target stimuli were either faces or nonsocial objects previously shown to be related to circumscribed interests in autism. The ASD group demonstrated relatively increased activation to social targets in right insular cortex and in left superior frontal gyrus and relatively decreased activation to nonsocial targets related to circumscribed interests in multiple frontostriatal brain regions. Findings suggest that frontostriatal recruitment during cognitive control in ASD is contingent on stimulus type, with increased activation for social stimuli and decreased activation for nonsocial stimuli related to circumscribed interests.

Convergent validity evidence for the Pain and Discomfort Scale (PADS) for pain assessment among adults with intellectual disability

Objectives:The main aim of the study was to generate initial convergent validity evidence for the Pain and Discomfort Scale (PADS) for use with nonverbal adults with intellectual disabilities. Materials and Methods:Forty-four adults with intellectual disability (mean age=46, 52% male) were evaluated using a standardized sham-controlled and blinded sensory testing protocol, from which Facial Action Coding System (FACS) and PADS scores were tested for (1) sensitivity to an array of calibrated sensory stimuli; (2) specificity (active vs. sham trials); and (3) concordance. Results:The primary findings were those participants who were reliably coded using both FACS and PADS approaches as being reactive to the sensory stimuli (FACS: F2,86=4.71, P<0.05, PADS: F2,86=21.49, P<0.05) (sensitivity evidence), not reactive during the sham stimulus trials (FACS: F1,43=3.77, P=0.06, PADS: F1,43=5.87, P=0.02) (specificity evidence), and there were significant (r=0.41 to 0.51, P<0.01) correlations between PADS and FACS (convergent validity evidence). Discussion:FACS is an objective coding platform for facial expression. It requires intensive training and resources for scoring. As such it may be limited for clinical application. PADS was designed for clinical application. PADS scores were comparable with FACS scores under controlled evaluation conditions providing partial convergent validity evidence for its use.

Social Orienting and Attention Is Influenced by the Presence of Competing Nonsocial Information in Adolescents with Autism

Background: Our experiences with the world play a critical role in neural and behavioral development. Children with autism spectrum disorder (ASD) spend a disproportionate amount of time seeking out, attending to, and engaging with aspects of their environment that are largely nonsocial in nature. In this study we adapted an established method for eliciting and quantifying aspects of visual choice behavior related to preference to test the hypothesis that preference for nonsocial sources of stimulation diminishes orientation and attention to social sources of stimulation in children with ASD. Method: Preferential viewing tasks can serve as objective measures of preference, with a greater proportion of viewing time to one item indicative of increased preference. The current task used gaze-tracking technology to examine patterns of visual orientation and attention to stimulus pairs that varied in social (faces) and nonsocial content (high autism interest or low autism interest). Participants included both adolescents diagnosed with ASD and typically developing; groups were matched on IQ and gender. Results: Repeated measures ANOVA revealed that individuals with ASD had a significantly greater latency to first fixate on social images when this image was paired with a high autism interest image, compared to a low autism interest image pairing. Participants with ASD showed greater total look time to objects, while typically developing participants preferred to look at faces. Groups also differed in number and average duration of fixations to social and object images. In the ASD group only, a measure of nonsocial interest was associated with reduced preference for social images when paired with high autism interest images. Conclusions: In ASD, the presence of nonsocial sources of stimulation can significantly increase the latency of look time to social sources of information. These results suggest that atypicalities in social motivation in ASD may be context-dependent, with a greater degree of plasticity than is assumed by existing social motivation accounts of ASD.

Vestibulo-ocular reflex function in children with high-functioning autism spectrum disorders

Sensorimotor processing alterations are a growing focus in the assessment and treatment of Autism Spectrum Disorders (ASD). The rotational vestibulo‐ocular reflex (rVOR), which functions to maintain stable vision during head movements, is a sensorimotor system that may be useful in understanding such alterations and their underlying neurobiology. In this study, we assessed post‐rotary nystagmus elicited by continuous whole body rotation among children with high‐functioning ASD and typically developing children. Children with ASD exhibited increased rVOR gain, the ratio of eye velocity to head velocity, indicating a possible lack of cerebellar inhibitory input to brainstem vestibular nuclei in this population. The ASD group also showed less regular or periodic horizontal eye movements as indexed by greater variance accounted for by multiple higher frequency bandwidths as well as greater entropy scores compared to typically developing children. The decreased regularity or dysrhythmia in the temporal structure of nystagmus beats in children with ASD may be due to alterations in cerebellum and brainstem circuitry. These findings could potentially serve as a model to better understand the functional effects of differences in these brain structures in ASD. Autism Res 2017, 10: 251–266.

A Cohesive Framework for Motor Stereotypy in Typical and Atypical Development: The Role of Sensorimotor Integration

Stereotyped motor behavior manifests as rhythmic, repetitive movements. It is common in several neurologic and psychiatric disorders where it is considered maladaptive. However, it also occurs early in typical development where it serves an adaptive function in the development of complex, controlled motor behavior. Currently, no framework accounts for both adaptive and maladaptive forms of motor stereotypy. We propose a conceptual model that implicates sensorimotor mechanisms in the phenomenology of adaptive and maladaptive stereotypy. The extensive structural and functional connectivity between sensory and motor neural circuits evidences the importance of sensory integration in the production of controlled movement. In support of our model, motor stereotypy in normative development occurs when the sensory and motor brain regions are immature and the infant has limited sensory and motor experience. With maturation and experience, complex movements develop and replace simple, stereotyped movements. This developmental increase in motor complexity depends on the availability of sensory feedback indicating that the integration of sensory information with ongoing movement allows individuals to adaptively cater their movements to the environmental context. In atypical development, altered neural function of sensorimotor circuitry may limit an individual’s ability to integrate sensory feedback to adapt movements to appropriately respond to environmental conditions. Consequently, the motor repertoire would remain relatively simple, resulting in the persistence of motor stereotypy. A framework that considers motor stereotypy as a manifestation of low motor complexity resulting from poor sensorimotor integration has many implications for research, identification and treatment of motor stereotypy in a variety of developmental disorders.

Adults with Autism and Adults with Depression Show Similar Attentional Biases to Social-Affective Images

Individuals with ASD have increased rates of depression compared to the general population. Repetitive cognition is a core feature of ASD; in typically developing adults, repetitive cognition has been associated with attentional biases to negative emotional material and increased prospective depression risk. We compared adults with ASD to typically developing adults with depression and never-depressed controls, using a paired preference paradigm sensitive to affective biases in the context of repetitive cognition. Both clinical cohorts oriented faster to negative social-emotional material and spent less time overall on positive material, compared to healthy controls. Exploratory analyses within ASD revealed specific influences of repetitive behavior on patterns of affective bias. Findings help pinpoint susceptibilities in ASD that may confer increased risk for depression.

Subgrouping Autism Based on Symptom Severity Leads to Differences in the Degree of Convergence between Core Feature Domains.

Existing models of autism spectrum disorder (ASD) disagree as to whether the core features should be conceptualized as convergent (related) or divergent (unrelated), and the few previous studies addressing this question have found conflicting results. We examined standardized parent ratings of symptoms from three domains (social, communication, repetitive behaviors) in large samples of typically developing children, children with ASD, and ASD subgroups. Our results suggest that the most evidence for divergence lies in typically developing children and lower severity ASD cases, while more evidence for convergence is found in a subset of cases with more severe impairment on any core feature. These results highlight the importance of subgrouping ASD given the degree of phenotypic heterogeneity present across the autism spectrum.