Studying caregiver-infant co-regulation in dynamic, diverse cultural contexts: A call to action

Caregiver greeting to infants under 6 months already reflects emerging differences in those later diagnosed with autism

As infants develop, caregivers adjust their behaviour to scaffold their infant's emerging skills, such that changes in infants' social abilities are expected to elicit changes in caregiver behaviour. We examined whether changes in the probability of infant-directed caregiving behaviour-specifically, greeting, a ubiquitous signal used by caregivers to initiate reciprocal interactions-differ between infant-caregiver dyads with an infant later diagnosed with autism and dyads with a neurotypically developing infant during infants' first 6 months. Using longitudinal data from 163 dyads, we found that caregivers in autism dyads (n = 40) used greeting less and at later infant ages than caregivers with a neurotypically developing infant (neurotypical dyads, n = 83). Caregivers in dyads with infants at elevated familial genetic likelihood for autism who did not receive an autism diagnosis (EL-non-autism dyads, n = 40) showed no differences in greeting compared with neurotypical dyads. Socioeconomic status partially mediated the difference between autism and neurotypical dyads. These findings show that autism and socioeconomic status were associated with the mutually adapted dynamics of dyadic interaction beginning in the first postnatal weeks. Importantly, differences in caregiver greeting observed in autism dyads are not interpreted as suboptimal behaviour from caregivers but rather indicate how early emerging social differences related to autism, years before overt features are present, may alter social learning opportunities elicited by the infant.

Childhood unpredictability research within the developmental psychopathology framework: Advances, implications, and future directions

Greater unpredictability in childhood from the level of the caregiver-child dyad to broader family, home, or environmental instability is consistently associated with disruptions in cognitive, socioemotional, behavioral, and biological development in humans. These findings are bolstered by experimental research in non-human animal models suggesting that early life unpredictability is an important environmental signal to the developing organism that shapes neurodevelopment and behavior. Research on childhood unpredictability has surged in the past several years, guided in part by theoretical grounding from the developmental psychopathology framework (shaped largely by Dr. Dante Cicchetti's innovative work). The current review focuses on future directions for unpredictability research, including probing intergenerational effects, the role of predictability in resilience, cultural and contextual considerations, and novel developmental outcomes that should be tested in relation to childhood unpredictability. We urge the integration of multidisciplinary perspectives and collaborations into future research on unpredictability. We also provide ideas for translating this research to real-world practice and policy and encourage high-quality research testing whether incorporating predictability into interventions and policy improves developmental outcomes, which would support further dissemination of these findings.

Spontaneous infant crying modulates vagal activity in real time

Porges' polyvagal theory (1991) proposes that the activity of the vagal nerve modulates moment-by-moment changes in adaptive behavior during stress. However, most work, including research with infants, has only examined vagal changes at low temporal resolutions, averaging 30+ s across phases of structured stressor paradigms. Thus, the true timescale of vagal regulation-and the extent to which it can be observed during unprompted crying-is unknown. The current study utilized a recently validated method to calculate respiratory sinus arrhythmia (RSA) dynamically at a high resolution of 5 Hz (updated every 200 ms) in a home-based infant study. Using an event-related analysis, we calculated the relative change in RSA around the onset of naturally occurring unprompted instances of n = 41 infants' 180 crying events. As predicted, RSA significantly decreased after the onset of crying compared to non-crying chance changes in RSA. Decreasing trends in RSA were driven by infants with higher pre-cry RSA values, infants rated lower in Negative Affectivity, and those rated both high and low in Orienting by their mothers. Our results display the timescale of RSA in spontaneous and naturalistic episodes of infant crying and that these dynamic RSA patterns are aligned with real-time levels of RSA and also caregiver-reported temperament.

Salivary secretory immunoglobulin A as a potential biomarker of psychosocial stress response during the first stages of life: A systematic review

Mucosal secretory immunoglobulin A (s-IgA) has been recognized as a key component of human first line defense against infection. However, its reactivity to psychosocial stressors is poorly understood. This systematic review aimed to explore whether s-IgA levels changed after psychosocial stress in subjects under the age of 18. Fifteen articles were included. s-IgA basal levels are increased in children older than 9 years old exposed to stress. Furthermore, s-IgA seems to follow a circadian rhythm, which is altered under stress conditions. Finally, the collective evidence suggests that salivary s-IgA rapidly increases under acute stress after puberty. Overall, our review indicates that s-IgA could be considered a potential psychosocial stress biomarker of interest for pediatric and child-juvenile psychiatric population. Further studies are needed to validate the role of s-IgA circadian rhythm and basal levels as psychosocial stress biomarkers and disentangle the role of age and type of stressor.

Infant crying predicts real-time fluctuations in maternal mental health in ecologically valid home settings

Exposure to infant crying is a well-established predictor of mothers' mental health. However, this association may reflect many potential mechanisms. Capturing dynamic fluctuations in mothers' states simultaneously with caregiving experiences is necessary to identify the real-time processes influencing mental health. In this study, we leveraged ecological momentary assessments (EMAs) and infant-worn audio recorders to capture variability in mothers' mental health symptoms and their exposure to infant crying over one week in a racially and socio-economically diverse urban North-American sample (N = 53). We use multilevel modeling to characterize within- and between-person effects of crying on maternal negative affect and symptoms of depression and anxiety. Within participants, when infants cried more than average in the 10 min, 1 hr, and 8 hr prior to an EMA report, mothers' negative affect subsequently increased, controlling for mean levels of infant crying. In contrast to findings from laboratory studies, in everyday settings crying exposure did not immediately increase feelings of depression. Only when crying was above average for 8 hr prior to EMA did mothers report increases in subsequent depression symptoms, suggesting that the effects of crying on maternal mental health take hours to unfold in ecologically valid home settings. Between participants, mothers of infants who cried more on average did not report higher negative affect or symptoms of depression or anxiety. Overall, our findings reveal that crying exposure dynamically influences maternal negative affect and depression but not anxiety in ecologically valid real-world settings. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Neurobiology of Parental Regulation of the Infant and Its Disruption by Trauma Within Attachment

The complex process of regulating physiological functions and homeostasis during external and internal disruptions develops slowly in altricial species, with parental care functioning as a co-regulator of infant physiological and emotional homeostasis. Here, we review our current understanding of the infant's use of parental behaviors for neurobehavioral regulation and its disruption with harsh parental care. Taking a cross-species view, we briefly review the human developmental literature that highlights the importance of the caregiver in scaffolding the child's physiological and emotional regulation, especially under threat and stress. We then use emerging corresponding animal literature within the phylogenetically preserved attachment system to help define neural systems supporting caregiver regulation and its supporting causal mechanism to provide translational bridges to inform causation and mechanisms impossible to define in children. Next, we briefly review animal research highlighting the impact of specific sensory stimuli imbedded in parental care as important for infant physiological and emotion regulation. We then highlight the importance of parental sensory stimuli gaining hedonic value to go beyond simple sensory stimuli to further impact neurobehavioral regulation, with poor quality of care compromising the infant's ability to use these cues for regulation. Clinically, parental regulation of the infant is correlated with later-life neurobehavioral outcome and quality of life. We suggest an understanding of this parental regulation of the infant's immediate neurobehavioral functioning within the context of attachment quality, that may provide insights into the complex processes during early life, initiating the pathway to pathology.

Clients' Emotional Experiences Tied to Therapist-Led (but Not Client-Led) Physiological Synchrony during Imagery Rescripting

Imagery rescripting (IR), an effective intervention technique, may achieve its benefits through various change mechanisms. Previous work has indicated that client–therapist physiological synchrony during IR may serve as one such mechanism. The present work explores the possibility that therapist-led vs. client-led synchrony may be differentially tied to clients’ emotional experiences in therapy. The analyses were conducted with data taken from an open trial of a brief protocol for treating test anxiety (86 IR sessions from 50 client–therapist dyads). Physiological synchrony in electrodermal activity was indexed using two cross-correlation functions per session: once for client leading and again for therapist leading (in both cases, with lags up to 10 s). The clients’ and therapists’ in-session emotions were assessed with the Profile of Mood States. Actor–partner interdependence models showed that certain client (but not therapist) in-session emotions, namely higher contentment and lower anxiety and depression, were tied to therapist-led (but not client-led) physiological synchrony. The results suggest that therapist-led synchrony (i.e., clients’ arousal tracking therapists’ earlier arousal) is tied to more positive and less negative emotional experiences for clients.