Understanding allostasis: Early-life self-regulation involves both up- and down-regulation of arousal.

Optimal performance lies at intermediate autonomic arousal, but no previous research has examined whether the emergence of endogenous control associates with changes in children's up-regulation from hypo-arousal, as well as down-regulation from hyper-arousal. We used wearables to take day-long recordings from N = 58, 12-month-olds (60% white/58% female); and, in the same infants, we measured self-regulation in the lab with a still-face paradigm. Overall, our findings suggest that infants who showed more self-regulatory behaviors in the lab were more likely to actively change their behaviors in home settings moment-by-moment "on the fly" following changes in autonomic arousal, and that these changes result in up- as well as down-regulation. Implications for the role of atypical self-regulation in later psychopathology are discussed.

Anxious parents show higher physiological synchrony with their infants.

BACKGROUND: Interpersonal processes influence our physiological states and associated affect. Physiological arousal dysregulation, a core feature of anxiety disorders, has been identified in children of parents with elevated anxiety. However, little is understood about how parent-infant interpersonal regulatory processes differ when the dyad includes a more anxious parent. METHODS: We investigated moment-to-moment fluctuations in arousal within parent-infant dyads using miniaturised microphones and autonomic monitors. We continually recorded arousal and vocalisations in infants and parents in naturalistic home settings across day-long data segments. RESULTS: Our results indicated that physiological synchrony across the day was stronger in dyads including more rather than less anxious mothers. Across the whole recording epoch, less anxious mothers showed responsivity that was limited to 'peak' moments in their child's arousal. In contrast, more anxious mothers showed greater reactivity to small-scale fluctuations. Less anxious mothers also showed behaviours akin to 'stress buffering' - downregulating their arousal when the overall arousal level of the dyad was high. These behaviours were absent in more anxious mothers. CONCLUSION: Our findings have implications for understanding the differential processes of physiological co-regulation in partnerships where a partner is anxious, and for the use of this understanding in informing intervention strategies for dyads needing support for elevated levels of anxiety.