Examining the feasibility and utility of heart rate variability on intervention outcomes targeting emotion regulation in autism: a brief report

Autistic youth experience several behavioral and emotional characteristics that can predispose them to emotion dysregulation (ED). Current literature examining ED in autism spectrum disorder (ASD) is limited to parent- and self-reported measures, indicating a need for biological or physiological methods to better assess emotion regulation in ASD. Utilizing the autonomic nervous system, specifically heart rate variability (HRV), may be a promising method to objectively measure ED in ASD, given it is one of the body's primary means of regulating physiological arousal. Our pilot study is one of the first to examine the feasibility, utility, and construct validity of HRV along with clinical measures within an intervention targeting ED-specific symptoms in ASD. Participants included 30 autistic youth ages 8-17 years who participated in the pilot study of Regulating Together, a group-based intervention targeting emotion regulation. We demonstrate HRV is feasible, demonstrates adequate test-retest reliability, and is complimentary to clinician- and parent-reported measures. Our preliminary findings also point to certain HRV profiles being indicative of long-term outcomes after receiving treatment. HRV may be a useful, objective tool in determining differential needs of long-term follow-up care for treatment maintenance at screening or baseline stages.

Wearable Biosensing to Predict Imminent Aggressive Behavior in Psychiatric Inpatient Youths With Autism

Importance

Aggressive behavior is a prevalent and challenging issue in individuals with autism.

Objective

To investigate whether changes in peripheral physiology recorded by a wearable biosensor and machine learning can be used to predict imminent aggressive behavior before it occurs in inpatient youths with autism.

Design, Setting, and Participants

This noninterventional prognostic study used data collected from March 2019 to March 2020 from 4 primary care psychiatric inpatient hospitals. Enrolled participants were 86 psychiatric inpatients with confirmed diagnoses of autism exhibiting operationally defined self-injurious behavior, emotion dysregulation, or aggression toward others; 16 individuals were not included (18.6%) because they would not wear the biosensor (8 individuals) or were discharged before an observation could be made (8 individuals). Data were analyzed from March 2020 through October 2023.

Main Outcomes and Measures

Research staff performed live behavioral coding of aggressive behavior while inpatient study participants wore a commercially available biosensor that recorded peripheral physiological signals (cardiovascular activity, electrodermal activity, and motion). Logistic regression, support vector machines, neural networks, and domain adaptation were used to analyze time-series features extracted from biosensor data. Area under the receiver operating characteristic curve (AUROC) values were used to evaluate the performance of population- and person-dependent models.

Results

There were 70 study participants (mean [range; SD] age, 11.9 [5-19; 3.5] years; 62 males [88.6%]; 1 Asian [1.4%], 5 Black [7.1%], 1 Native Hawaiian or Other Pacific Islander [1.4%], and 63 White [90.0%]; 5 Hispanic [7.5%] and 62 non-Hispanic [92.5%] among 67 individuals with ethnicity data). Nearly half of the population (32 individuals [45.7%]) was minimally verbal, and 30 individuals (42.8%) had an intellectual disability. Participant length of inpatient hospital stay ranged from 8 to 201 days, and the mean (SD) length was 37.28 (33.95) days. A total of 429 naturalistic observational coding sessions were recorded, totaling 497 hours, wherein 6665 aggressive behaviors were documented, including self-injury (3983 behaviors [59.8%]), emotion dysregulation (2063 behaviors [31.0%]), and aggression toward others (619 behaviors [9.3%]). Logistic regression was the best-performing overall classifier across all experiments; for example, it predicted aggressive behavior 3 minutes before onset with a mean AUROC of 0.80 (95% CI, 0.79-0.81).

Conclusions and Relevance

This study replicated and extended previous findings suggesting that machine learning analyses of preceding changes in peripheral physiology may be used to predict imminent aggressive behaviors before they occur in inpatient youths with autism. Further research will explore clinical implications and the potential for personalized interventions.

Parent-Child Cohesion and College Students' Positive/Negative Affect: The Moderating Roles of Sympathetic Nervous System Activity and Parent-Child Separation Experience

Parent-child separation caused by parental migration could have adverse effects on individuals' emotional adaptation. However, research on this topic is limited in its focus on childhood or adolescence samples and solely environmental factors, and less is known about how positive environmental factors, biological factors and parent-child separation experience interact to influence emotional adaptation in emerging adulthood. The present study addressed these issues by investigating the relationships between parent-child cohesion and positive/negative affect, and examining the moderating roles of sympathetic nervous system activity (measured by skin conductance level reactivity, SCLR) and parent-child separation experience in the relationships. Data from 248 college students (M_age = 18.91 years, SD = 0.70; 32.3% males), including 158 college students with parent-child separation experience and 90 college students without parent-child separation experience. The results showed that parent-child cohesion predicted college students' positive/negative affect. Moreover, the moderating role of SCLR on the relationship between father-child cohesion and negative affect varied with parent-child separation experience. Specifically, father-child cohesion negatively predicted negative affect when SCLR was lower for college students with parent-child separation experience, while negatively predicted negative affect when SCLR was higher for college students without parent-child separation experience. These results indicate that the interaction pattern of Biological × Environmental predicting college students' positive/negative affect varies across parent-child separation status in childhood or adolescence.

Childhood Adversity, Emotional Well-Being, Loneliness, and Optimism: a National Study

Optimism and loneliness, which reflect the expected inverse associations with excess morbidity and mortality, are theoretically and empirically associated with early adversities and offer potential avenues for clinical support. The current study first estimates latent classes of adverse childhood experiences and, second, assesses the role of these experiences on later reports of optimism and loneliness in late adolescence and emerging adulthood, and the role of emotional regulation and common mental disorders. Surveys were conducted in a longitudinal household sample of adolescents recruited in 2013 (average age of 20 at wave 6 follow-ups). The analytic sample included 1177 female and male respondents representative of their age group in the USA at baseline. Latent classes were estimated based on 10 indicators of childhood adversity. Respondents were assigned to classes using posterior probabilities of latent class membership, and class membership was used to predict psychological outcomes in multivariable models. Three latent classes of childhood adversity were identified in the current sample, representing low childhood adversity (81.5%), higher probability of family dysfunction with lower levels of interpersonal abuse (13.4%), and high adversity including higher probabilities of parental discord and violence as well as child abuse (5.1%). Both classes of respondents who faced greater childhood adversity were more likely to report greater loneliness and lower optimism in emerging adulthood. Results were attenuated by measures of emotional well-being. Addressing adolescent loneliness and supporting optimistic outlooks in emerging adulthood are two pathways with potential benefits to reduce mental and physical morbidities.

Eye pupil – a window into central autonomic regulation via emotional/cognitive processing

If the eyes are windows into the soul, then the pupils represent at least the gateway to the brain and can provide a unique insight into the human mind from several aspects. The changes in the pupil size primarily mediated by different lighting conditions are controlled by the autonomic nervous system regulated predominantly at the subcortical level. Specifically, parasympathetically-linked pupillary constriction is under the Edinger-Westphal nucleus control and sympathetically-mediated pupillary dilation is regulated from the posterior hypothalamic nuclei. However, the changes in the pupil size can be observed at resting state even under constant lighting, these pupillary changes are mediated by global arousal level as well as by various cognitive factors. In this context, autonomic pathways modulating changes in the pupil size in response to the different light levels can be influenced by multiple central descending inputs driving pupillary changes under steady lighting conditions. Moreover, as the pupillary response is involved in emotional (task-evoked pupillary dilation as an index of emotional arousal) and cognitive (task-evoked pupillary dilation as an index of cognitive workload) stimulation, it can be used to detect the impact of mutual subcortical and cortical structures (i.e. overlapping brain structures included in autonomic, emotional and cognitive regulation) on the pupillary innervation system. Thus, complex understanding of the baseline pupil size´ and pupillary dynamics´ mechanisms may provide an important insight into the central nervous system functioning pointing to the pupillometry as a promising tool in the clinical application.

Eye pupil - a window into central autonomic regulation via emotional/cognitive processing

If the eyes are windows into the soul, then the pupils represent at least the gateway to the brain and can provide a unique insight into the human mind from several aspects. The changes in the pupil size primarily mediated by different lighting conditions are controlled by the autonomic nervous system regulated predominantly at the subcortical level. Specifically, parasympathetically-linked pupillary constriction is under the Edinger-Westphal nucleus control and sympathetically-mediated pupillary dilation is regulated from the posterior hypothalamic nuclei. However, the changes in the pupil size can be observed at resting state even under constant lighting, these pupillary changes are mediated by global arousal level as well as by various cognitive factors. In this context, autonomic pathways modulating changes in the pupil size in response to the different light levels can be influenced by multiple central descending inputs driving pupillary changes under steady lighting conditions. Moreover, as the pupillary response is involved in emotional (task-evoked pupillary dilation as an index of emotional arousal) and cognitive (task-evoked pupillary dilation as an index of cognitive workload) stimulation, it can be used to detect the impact of mutual subcortical and cortical structures (i.e. overlapping brain structures included in autonomic, emotional and cognitive regulation) on the pupillary innervation system. Thus, complex understanding of the baseline pupil size´ and pupillary dynamics´ mechanisms may provide an important insight into the central nervous system functioning pointing to the pupillometry as a promising tool in the clinical application.

Neurobiological mechanisms of early life adversity, blunted stress reactivity and risk for addiction

Blunted stress reactivity resulting from early exposure to stress during childhood and adolescence may increase vulnerability to addiction. Early life adversity (ELA) affects brain structure and function and results in blunted stress axis reactivity. In this review, we focus on the underlying neurobiological mechanisms associated with a blunted response to stress, ELA, and risk for addictive disorders. ELA and blunted reactivity are accompanied by unstable mood regulation, impulsive behaviors, and reduced cognitive function. Neuroimaging studies reveal cortical and subcortical changes in persons exposed to ELA and those who have a genetic disposition for addiction. We propose a model in which blunted stress reactivity may be a marker of risk for addiction through an altered motivational and behavioral reactivity to stress that contribute to disinhibited behavioral reactivity and impulsivity leading in turn to increased vulnerability for substance use. Evidence supporting this hypothesis in the context of substance use initiation, maintenance, and risk for relapse is presented. The effects of ELA on persons at risk for addiction may lead to early experimentation with drugs of abuse. Early adoption of drug intake may alter neuroregulation in such vulnerable persons leading to a permanent dysregulation of motivational responses consistent with dependence. This article is part of the special issue on 'Vulnerabilities to Substance Abuse'.

Pupil Response to Affective Stimuli: a Biomarker of Early Conduct Problems in Young Children

Childhood conduct problems have been associated with reduced autonomic arousal to negative cues indicative of an insensitivity to aversive stimuli, with mixed evidence in response to positive cues. Autonomic arousal to affective stimuli has traditionally been measured through galvanic skin responses and heart-rate, despite evidence that pupillometry is more reliable and practically beneficial (i.e., no wires are attached to the participant). The current study is the first to examine abnormal pupillary responsivity to affective stimuli as a biomarker for childhood conduct problems. We measured pupil reactivity to negative, positive and neutral images in 131 children aged 4-7 years, who were referred by their teachers for being at risk of future psychopathology. We assessed relationships between pupil response to the images and teacher-rated scores on the Strengths and Difficulties Questionnaire (SDQ), which indexed child conduct problems and their overlapping emotional, behavioural and social difficulties. Reduced pupil dilation to negative images was associated with significantly increased conduct, hyperactivity, emotional and peer problems, as well as reduced prosocial behaviour. Composite scores for disruptive behaviour and emotional difficulties both uniquely predicted blunted pupil response to negative threat stimuli; there were no relations with pupil responses to positive images. These findings highlight that blunted pupil responsivity to negative stimuli serves as a biomarker for early disruptive behavioural problems and affective difficulties. Pupillometry offers an inexpensive, fast and non-intrusive measure to help identify children who are showing early disruptive behaviour or experiencing affective difficulties, which can provide opportunities for preventative intervention to avoid further psychopathology.

Predicting aggression to others in youth with autism using a wearable biosensor

Unpredictable and potentially dangerous aggressive behavior by youth with Autism Spectrum Disorder (ASD) can isolate them from foundational educational, social, and familial activities, thereby markedly exacerbating morbidity and costs associated with ASD. This study investigates whether preceding physiological and motion data measured by a wrist-worn biosensor can predict aggression to others by youth with ASD. We recorded peripheral physiological (cardiovascular and electrodermal activity) and motion (accelerometry) signals from a biosensor worn by 20 youth with ASD (ages 6-17 years, 75% male, 85% minimally verbal) during 69 independent naturalistic observation sessions with concurrent behavioral coding in a specialized inpatient psychiatry unit. We developed prediction models based on ridge-regularized logistic regression. Our results suggest that aggression to others can be predicted 1 min before it occurs using 3 min of prior biosensor data with an average area under the curve of 0.71 for a global model and 0.84 for person-dependent models. The biosensor was well tolerated, we obtained useable data in all cases, and no users withdrew from the study. Relatively high predictive accuracy was achieved using antecedent physiological and motion data. Larger trials are needed to further establish an ideal ratio of measurement density to predictive accuracy and reliability. These findings lay the groundwork for the future development of precursor behavior analysis and just-in-time adaptive intervention systems to prevent or mitigate the emergence, occurrence, and impact of aggression in ASD. Autism Res 2019, 12: 1286-1296. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Unpredictable aggression can create a barrier to accessing community, therapeutic, medical, and educational services. The present study evaluated whether data from a wearable biosensor can be used to predict aggression to others by youth with autism spectrum disorder (ASD). Results demonstrate that aggression to others can be predicted 1 min before it occurs with high accuracy, laying the groundwork for the future development of preemptive behavioral interventions and just-in-time adaptive intervention systems to prevent or mitigate the emergence, occurrence, and impact of aggression to others in ASD.

Emotional Underarousal and Overarousal and Engagement in Relational Aggression: Interactions between Relational Victimization, Physiological Reactivity, and Emotional Sensitivity

The present study examined if overarousal (i.e., dysregulation and high emotional sensitivity) and underarousal (i.e., fearlessness and emotional insensitivity) to peer stress, reflected in physiological reactivity and subjective emotional sensitivity, exacerbated risk for relational aggression in relationally victimized children. Participants were a community sample of 125 children (10-12 years, M = 11.34 years, SD = 0.89; 45% female). Teachers provided ratings of children's relational victimization and relational aggression. Children's physiological reactivity was assessed based on skin conductance level (SCL) reactivity and respiratory sinus arrhythmia (RSA) reactivity to a standardized peer rejection task. Children's subjective emotional sensitivity was assessed using self-reported ratings of distress to hypothetical relational provocation vignettes. Results indicated that relational victimization was significantly associated with relational aggression only for children with high SCL reactivity and high emotional sensitivity (i.e., physiological and subjective overarousal) and for children with low SCL reactivity and low emotional sensitivity (i.e., physiological and subjective underarousal); relational victimization did not predict relational aggression among children with high SCL reactivity but low emotional sensitivity or among children with low SCL reactivity but high emotional sensitivity. Relational victimization was also marginally more strongly associated with relational aggression for children displaying RSA augmentation. Results suggest emotional overarousal and underarousal may both serve as vulnerabilities for relational aggression among relationally victimized youth, and underscore the importance of including physiological and subjective indices of emotional reactivity in studies of aggression. Implications for theory and intervention are discussed.

Marching to the beat of your own drum?: A proof-of-concept study assessing physiological linkage in Autism Spectrum Disorder

Autism Spectrum Disorder (ASD) is a neurodevelopmental condition characterized by difficulty in dynamically adjusting behavior to interact effectively with others, or social reciprocity. Synchronization of physiological responses between interacting partners, or physiological linkage (PL), is thought to provide a foundation for social reciprocity. In previous work we developed a new technique to measure PL using dynamic linear time series modeling to assess cardiac interbeat interval (IBI) linkage in typically developing same-sex unacquainted dyads (Scarpa et al., 2017). The current article describes a proof-of-concept study with three dyads of young adults with ASD interacting with same-sex unacquainted typically developing (TD) partners. This pilot data is applied to propose potential benefits of using this technique to quantify and assess PL in individuals with ASD, both for basic research and for intervention science. Discussion focuses on applications of this measure to potentially advance knowledge of the biology-behavior link in ASD.

Proactive and Reactive Aggression Subgroups in Typically Developing Children: The Role of Executive Functioning, Psychophysiology, and Psychopathy

This study aimed to assess whether groups of aggressive children differed on psychopathic traits, and neuropsychological and neurobiological measures of prefrontal functioning consistent with the objectives of their aggression-reactive or proactive. Including 110 typically developing children (9-11 years), a latent class analysis identified a low aggression group, a high reactive aggression group, and a mixed (high reactive and proactive) aggression group. Results show high callous-unemotional traits and low resting respiratory sinus arrhythmia increased the likelihood of children being in the mixed aggression group, when compared to the reactive and low aggression groups. However, deficits in planning and inhibitory control increased the likelihood of children being in the reactive aggression group, when compared to the mixed and low aggression groups. Executive functioning deficits did not differentiate the mixed group from the low aggression group. These findings highlight psychobiological and executive functioning differences that may explain heterogeneity in childhood aggression.

Stress and Addiction: When a Robust Stress Response Indicates Resiliency

OBJECTIVE

Stress reactivity research has traditionally focused on the idea that exaggerated responses to stress may have adverse effects on health. Accumulating evidence suggests that attenuated responses to stress and delayed recovery may also be problematic.

METHODS

This review focuses on the role of the stress response of the hypothalamic-pituitary-adrenocortical axis, the endogenous opioid system, and the cardiovascular system in hypertension, pain perception, and addictive behaviors. Results from multiple methods of assessment and stress paradigms conducted in our laboratory over the past two decades are integrated with research from other investigators and with existing theories.

RESULTS

Research indicates that exaggerated biological and physiological responses to stress and attenuated pain perception are associated with hypertension and risk for cardiovascular diseases. This research complements work linking reduced stress responses with enhanced pain sensitivity and discomfort. Multiple studies have also demonstrated that an attenuated stress response is linked to exacerbation of withdrawal symptoms and relapse in nicotine addiction. Evidence indicates important moderators (i.e., sex, personality traits, and early life adversity) and hypothalamic-pituitary-adrenocortical- and endogenous opioid system-related mechanisms in the altered response to stress. I integrate these findings in a conceptual model emphasizing that robust stress responses in the context of addiction and relapse should be considered as a marker of resiliency.

CONCLUSIONS

A blunted stress response may indicate long-term physiological dysregulation that could usher harmful consequences for cardiovascular disease, pain perception, and addictive disorders. The impact of dysregulation is influenced by multiple individual and situational factors that should be considered in evaluating the clinical significance of stress response dysregulation.

Heart rate, health, and hurtful behavior

Hostility is a risk factor for cardiovascular events. When challenged, individuals high on hostility exhibit a hyperreactive psychophysiological response to stressors, thereby increasing risk for developing cardiovascular disease. However, low resting heart rate (HR) is associated with physical aggression and hostility in children, adolescents, and adults. Based on a community sample of 296 men (mean age = 32.0), we (a) address whether aggression/hostility relates to physical health through relationships with cardiovascular levels at rest and in response to stressors, and (b) determine how relations between aggression and health are altered by including psychophysiological indices in statistical models. The Cook-Medley cynical/hostile attitudes and the Buss-Perry physical aggression and hostility measures assessed aggression. Health was assessed as systolic blood pressure (SBP), report of medical conditions, and a metabolic composite. Reactivity to stressors was assessed with HR, SBP, and diastolic blood pressure. Aggression was negatively related to both resting HR and reactivity. High resting HR and reactivity were, however, positively related to poor health. Thus, the relationship between aggression and HR and reactivity suppressed an overall relationship between high aggression/hostility and poor health. In the presence of covariates for socioeconomic status, race, health behaviors, and medications, the relationship between aggression and health was significantly strengthened when HR level and reactivity were included in models. In sum, at early midlife, low HR among aggressive and hostile individuals is related to less health risk. Aggression and hostility have a deleterious influence on health, but primarily among individuals with higher HR and possibly greater cardiovascular reactivity.