Atypical Emotional Electrodermal Activity in Toddlers with Autism Spectrum Disorder

Comparative analysis of electrodermal activity metrics and their association with child behavior in autism spectrum disorder

Researchers are increasingly utilizing physiological data like electrodermal activity (EDA) to understand how stress "gets under the skin." Results of EDA studies in autistic children are mixed, with some suggesting autistic hyperarousal, others finding hypoarousal, and yet others detecting no difference compared to non-autistics. Some of this variability likely stems from the different techniques used to assess EDA. Therefore, the purpose of this study is to investigate and compare commonly used metrics of EDA (frequency of peaks, average amplitude of peaks, and standard deviation of skin conductance level) using two data processing programs (NeuroKit2 and Ledalab) and their link to observed child behavior. EDA data were collected using Empatica E4 wristbands from 60 autistic children and adolescents (5-18 years old) during a 7-min play interaction with their primary caregiver. The play interaction was coded for a range of child behaviors including mood, social responsiveness, dysregulation, and cooperation. Results indicate a strong correlation between NeuroKit2 and Ledalab and a weak correlation between metrics within each program. Furthermore, the frequency of peaks was associated with more positive child social behaviors, and the magnitude of peaks was associated with less adaptive child behaviors. Recommendations for replication and the need for generalizability of this research are given.

Child emotion lability is associated with within-task changes of autonomic activity during a mirror-tracing task

Adaptive biological and emotional stress responding are both critical for healthy human development. However, the complex associations between the two are not fully understood. The current study addresses this gap in research by studying associations of child emotion regulation and lability with within-task changes in the biological stress response during a mirror-tracing task. Participants were 59 families including two parents and a child between 5 and 12 years old (52.2% female). Parents reported on family demographics and completed the Emotion Regulation Checklist. Child skin conductance level (SCL) and respiratory sinus arrhythmia (RSA) were recorded during a baseline task and during a 3-minute mirror-tracing task. Within-task patterns of SCL and RSA during the task were estimated with multilevel modeling (measures within persons). The emotion regulation subscale was unrelated to any facet of SCL/RSA time courses. However, lower emotion lability was related to SCL patterns that changed less during the task and were overall lower. For RSA, lower emotion lability was related to higher initial RSA that significantly decreased during the task. These findings suggest that higher child emotion lability may promote increased physiological arousal of target organs during challenging activities.

A scoping review of physiological biomarkers in autism

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by pervasive deficits in social interaction, communication impairments, and the presence of restricted and repetitive behaviors. This complex disorder is a significant public health concern due to its escalating incidence and detrimental impact on quality of life. Currently, extensive investigations are underway to identify prospective susceptibility or predictive biomarkers, employing a physiological biomarker-based framework. However, knowledge regarding physiological biomarkers in relation to Autism is sparse. We performed a scoping review to explore putative changes in physiological activities associated with behaviors in individuals with Autism. We identified studies published between January 2000 and June 2023 from online databases, and searched keywords included electroencephalography (EEG), magnetoencephalography (MEG), electrodermal activity markers (EDA), eye-tracking markers. We specifically detected social-related symptoms such as impaired social communication in ASD patients. Our results indicated that the EEG/ERP N170 signal has undergone the most rigorous testing as a potential biomarker, showing promise in identifying subgroups within ASD and displaying potential as an indicator of treatment response. By gathering current data from various physiological biomarkers, we can obtain a comprehensive understanding of the physiological profiles of individuals with ASD, offering potential for subgrouping and targeted intervention strategies.

Prevalence and Phenomenology of Anxiety in Preschool-Aged Children with Autism Spectrum Disorder

Individuals with autism spectrum disorder (ASD) are at a higher risk for developing co-occurring anxiety symptoms and diagnosable anxiety disorders compared to children with neurotypical development (NTD). The objective of the current study was to characterize the prevalence and phenomenology of anxiety in preschool-aged children with ASD. Our sample consisted of preschoolers (M = 52.8 months, SD = 10.8 months) with ASD (n = 77, 66% with co-occurring intellectual disability, ID) and NTD (n = 55). We employed multi-method (questionnaire and semi-structured diagnostic interview) and multi-informant (parent- and teacher-report) assessments of anxiety. Children with ASD were significantly more likely to meet criteria for an anxiety disorder than children with NTD. Over 70% of our sample with ASD met DSM-5 criteria for an anxiety disorder, with Specific Phobia and Separation Anxiety Disorder being the most prevalent. A range of specific fears was endorsed in the group with ASD, many of which overlapped with ASD symptoms. Parents, but not teachers, also reported greater anxiety symptoms for children with ASD relative to the comparison sample. Prevalence and phenomenology of anxiety in our sample with ASD generally did not differ between those with and without co-occurring ID, with the exception of higher rates of generalized anxiety in those without ID. Results showed poor concordance between parent questionnaires and a semi-structured diagnostic interview in detecting clinically-elevated anxiety in children with ASD. Implications for clinical practice and research are discussed.

Emotional and sensory dysregulation as a possible missing link in attention deficit hyperactivity disorder: A review

Attention Deficit Hyperactivity Disorder (ADHD) is a common developmental disorder affecting 5-7% of adults and children. We surveyed the literature to examine ADHD through three pillars: developmental characteristics, symptomatology, and treatment strategies. Firstly, in terms of developmental characterstics, early life stress may increase the risk of developing ADHD symptoms according to animal models' research. Secondly, the current core symptoms of ADHD are comprised of inattention, hyperactivity, and impulsivity. However, the up-to-date literature indicates individuals with ADHD experience emotional and sensory dysregulation as well, which early-life stress may also increase the risk of. Finally, we discuss the therapeutic benefits of methylphenidate on both the current core ADHD symptoms and the sensory and emotional dysregulation found in those with ADHD. In summation, we surveyed the recent literature to analyze (i) the potential role of early-life stress in ADHD development, (ii) the involvement of emotional and sensory dysregulation in ADHD symptomatology and finally, (iii) the therapeutic intervention with methylphenidate, aiming to reduce the potential effect of early life stress in ADHD, and mainly emotional and sensory dysregulation. The apparent but currently less recognized additional symptoms of emotional and sensory dysregulation in ADHD call for further investigation of these possible causes and thus increasing treatments efficacy in individuals with ADHD.

Autism Spectrum Disorder in Children Is Not Associated With Abnormal Autonomic Nervous System Function: Hypothesis and Theory

The quest to understand the pathophysiology of autism spectrum disorder (ASD) has led to extensive literature that purports to provide evidence for autonomic dysfunction based on heart rate and heart rate variability (HRV), in particular respiratory sinus arrhythmia (RSA), a measure of parasympathetic functioning. Many studies conclude that autism is associated with vagal withdrawal and sympathetic hyperactivation based on HRV and electrodermal analyses. We will argue that a critical analysis of the data leads to the hypothesis that autonomic nervous system dysfunction is not a dominant feature of autism. Most children with ASD have normal parasympathetic baseline values and normal autonomic responses to social stimuli. The existing HRV and electrodermal data cannot lead to the conclusion of an over-excitation of the sympathetic nervous system. A small subgroup of ASD children in experimental settings has relatively low RSA values and relatively high heart rates. The data suggest that this is likely associated with a relatively high level of anxiety during study conditions, associated with co-morbidities such as constipation, or due to the use of psychoactive medication. Many studies interpret their data to conform with a preferred hypothesis of autonomic dysfunction as a trait of autism, related to the polyvagal theory, but the HRV evidence is to the contrary. HRV analysis may identify children with ASD having autonomic dysfunction due to co-morbidities.

Puppets facilitate attention to social cues in children with ASD

Diminished visual attention to faces of social partners represents one of the early characteristics of autism spectrum disorder (ASD). Here we examine if the introduction of puppets as social partners alters attention to speakers' faces in young children with ASD and typically developing (TD) controls. Children with ASD (N = 37; Mage  = 49.44 months) and TD (N = 27; Mage  = 40.66 months) viewed a video depicting a puppet and a human engaged in a conversation. Dwell time on these faces was analyzed as a function of group and speaker's identity. Unlike TD controls, the ASD group exhibited limited visual attention to and chance-level visual preference for the human speaker. However, attention to and preference for the puppet speaker's face was greater than chance and comparable across the two groups. While there was a strong association between low human speaker preference and high autism severity, no association with autism severity was found for puppet speaker preference. Unlike humans, expressive and verbal puppets attracted the attention of children with ASD at levels comparable to that of TD controls. Considering that puppets can engage in reciprocal interactions and deliver simplified, salient social-communicative cues, they may facilitate therapeutic efforts in children with ASD. LAY SUMMARY: While studies have shown support for therapeutic uses of robots with children with autism, other similar agents such as puppets remain to be explored. When shown a video of a conversation between a puppet and a person, young children with ASD paid as much attention to the puppet's face as typically-developing (TD) children. Since puppets can engage in back-and-forth interactions and model social interactions and communication, they may play a promising role in therapeutic efforts for young children with ASD.

Attend Less, Fear More: Elevated Distress to Social Threat in Toddlers With Autism Spectrum Disorder

Differential emotional reactivity to social and nonsocial stimuli has been hypothesized but rarely examined empirically in ASD despite its potential importance for development of social motivation, cognition, and comorbid psychopathology. This study examined emotional reactivity, regulation, and attention to social and nonsocial threat in toddlers with ASD (n = 42, M_age : 22 months) and typically developing (TD) toddlers (n = 22, M_age : 23 months), and their mutual associations with autism symptom severity. Participants were exposed to social (stranger), nonsocial (mechanical objects), and ambiguous (masks) threats, and their intensity of distress (iDistress), attention to threat (Attention), and presence of emotion regulation (ER) strategies were measured. Autism symptom severity was quantified using the Autism Diagnostic Observation Schedule-2. In response to social threat, toddlers with ASD exhibited elevated iDistress (P < 0.038) but lower Attention (P < 0.002) and a wider variety of ER strategies (P < 0.040) compared to TD controls, though their ER strategies were less likely to be social. However, nonsocial and ambiguous threat elicited lower iDistress in ASD than in TD toddlers (P = 0.012 and P = 0.034, respectively), but comparable Attention and ER strategy use. Autism severity was not associated with iDistress. The study demonstrates elevated emotional salience but diminished attentional salience of social threat in ASD. A failure to attend adequately to social threats may restrict opportunities to appraise their threat value and engender often observed in ASD negative emotional responses to novel social situations. Early atypical emotional reactivity may independently contribute to the shaping of complex autism phenotypes and may be linked with later emerging affective and behavioral symptoms. LAY SUMMARY: Compared to typically developing toddlers, toddlers with ASD show diminished attention yet enhanced distress in response to social threat. Poor attention to potential social threat may limit opportunities to assess its threat value and thus contribute to often observed negative emotional responses to novel social situations. Identifying the precursors of atypical emotional reactivity in infancy and its links with later psychopathology will inform about novel treatment targets and mechanisms of change in the early stages of ASD. Autism Res 2021, 14: 1025-1036. © 2020 International Society for Autism Research, Wiley Periodicals, LLC.

The Relationship between Autism and Ehlers-Danlos Syndromes/Hypermobility Spectrum Disorders

Considerable interest has arisen concerning the relationship between hereditary connective tissue disorders such as the Ehlers-Danlos syndromes (EDS)/hypermobility spectrum disorders (HSD) and autism, both in terms of their comorbidity as well as co-occurrence within the same families. This paper reviews our current state of knowledge, as well as highlighting unanswered questions concerning this remarkable patient group, which we hope will attract further scientific interest in coming years. In particular, patients themselves are demanding more research into this growing area of interest, although science has been slow to answer that call. Here, we address the overlap between these two spectrum conditions, including neurobehavioral, psychiatric, and neurological commonalities, shared peripheral neuropathies and neuropathologies, and similar autonomic and immune dysregulation. Together, these data highlight the potential relatedness of these two conditions and suggest that EDS/HSD may represent a subtype of autism.

Comparison of Wearable and Clinical Devices for Acquisition of Peripheral Nervous System Signals

A key access point to the functioning of the autonomic nervous system is the investigation of peripheral signals. Wearable devices (WDs) enable the acquisition and quantification of peripheral signals in a wide range of contexts, from personal uses to scientific research. WDs have lower costs and higher portability than medical-grade devices. However, the achievable data quality can be lower, and data are subject to artifacts due to body movements and data losses. It is therefore crucial to evaluate the reliability and validity of WDs before their use in research. In this study, we introduce a data analysis procedure for the assessment of WDs for multivariate physiological signals. The quality of cardiac and electrodermal activity signals is validated with a standard set of signal quality indicators. The pipeline is available as a collection of open source Python scripts based on the pyphysio package. We apply the indicators for the analysis of signal quality on data simultaneously recorded from a clinical-grade device and two WDs. The dataset provides signals of six different physiological measures collected from 18 subjects with WDs. This study indicates the need to validate the use of WDs in experimental settings for research and the importance of both technological and signal processing aspects to obtain reliable signals and reproducible results.

Atypical Emotional Electrodermal Activity in Toddlers with Autism Spectrum Disorder

Past studies in autism spectrum disorder (ASD) indicate atypical peripheral physiological arousal. However, the conditions under which these atypicalities arise and their link with behavioral emotional expressions and core ASD symptoms remain uncertain. Given the importance of physiological arousal in affective, learning, and cognitive processes, the current study examined changes in skin conductance level (ΔSCL) in 41 toddlers with ASD (mean age: 22.7 months, SD: 2.9) and 32 age-matched toddlers with typical development (TD) (mean age: 21.6 months, SD: 3.6) in response to probes designed to induce anger, joy, and fear emotions. The magnitude of ΔSCL was comparable during anger (P = 0.206, d = 0.30) and joy (P = 0.996, d = 0.01) conditions, but significantly lower during the fear condition (P = 0.001, d = 0.83) in toddlers with ASD compared to TD peers. In the combined samples, ΔSCL positively correlated with intensity of behavioral emotional expressivity during the anger (r[71] = 0.36, P = 0.002) and fear (r[68] = 0.32, P = 0.007) conditions, but not in the joy (r[69] = -0.15, P = 0.226) condition. Finally, ΔSCL did not associate with autism symptom severity in any emotion-eliciting condition in the ASD group. Toddlers with ASD displayed attenuated ΔSCL to situations aimed at eliciting fear, which may forecast the emergence of highly prevalent internalizing and externalizing problems in this population. The study putatively identifies ΔSCL as a dimension not associated with severity of autism but with behavioral responses in negatively emotionally challenging events and provides support for the feasibility, validity, and incipient utility of examining ΔSCL in response to emotional challenges in very young children. LAY SUMMARY: Physiological arousal was measured in toddlers with autism exposed to frustrating, pleasant, and threatening tasks. Compared to typically developing peers, toddlers with autism showed comparable arousal responses to frustrating and pleasant events, but lower responses to threatening events. Importantly, physiological arousal and behavioral expressions were aligned during frustrating and threatening events, inviting exploration of physiological arousal to measure responses to emotional challenges. Furthermore, this study advances the understanding of precursors to emotional and behavioral problems common in older children with autism. Autism Res 2020, 13: 1476-1488. © 2020 International Society for Autism Research, Wiley Periodicals, Inc.