Humming and Homeostasis: Insights from Infants, Mothers, Mantras and Caregiving.

Humming is a ubiquitous yet understudied form of human vocalisation that may play a role in regulating internal bodily states during early development. Unlike speech or singing with lyrics, humming consists of continuous, semantically unstructured vocal sounds produced with a closed mouth. It generates sustained sonic, vibratory and respiratory patterns that engage interoceptive and autonomic processes. This paper explores the hypothesis that humming critically contributes to homeostatic regulation in caregiver-infant interaction. Drawing on research in developmental psychology, perinatal care and vocal practice, we propose that humming provides a simple mechanism through which caregivers may scaffold the infant's developing interoceptive awareness, paving the way to subsequent social cognition abilities. Through slow rhythmic breathing, chest and cranial vibration, and temporally structured vocal phrasing, humming may influence cardio-respiratory rhythms and support autonomic balance while also organising moments of social engagement. Evidence is gathered from studies of maternal humming during kangaroo care with preterm infants, showing that these vocalisations can stabilise physiological parameters and invite infant vocal participation. We argue that humming may function as an embodied, interoceptive form of co-regulation for both infants and caregivers, linking physiological homeostasis with early communicative exchange.