The calming effect of maternal carrying in different mammalian species

Abstract

Attachment theory postulates that mothers and their infants possess some basic physiological mechanisms that favor their dyadic interaction and bonding. Many studies have focused on the maternal physiological mechanisms that promote attachment (e.g., mothers’ automatic responses to infant faces and/or cries), and relatively less have examined infant physiology. Thus, the physiological mechanisms regulating infant bonding behaviors remain largely undefined. This review elucidates some of the neurobiological mechanisms governing social bonding and cooperation in humans by focusing on maternal carrying and its beneficial effect on mother–infant interaction in mammalian species (e.g., in humans, big cats, and rodents). These studies show that infants have a specific calming response to maternal carrying. A human infant carried by his/her walking mother exhibits a rapid heart rate decrease, and immediately stops voluntary movement and crying compared to when he/she is held in a sitting position. Furthermore, strikingly similar responses were identified in mouse rodents, who exhibit immobility, diminished ultra-sonic vocalizations and heart rate. In general, the studies described in the current review demonstrate the calming effect of maternal carrying to be comprised of a complex set of behavioral and physiological components, each of which has a specific postnatal time window and is orchestrated in a well-matched manner with the maturation of the infants. Such reactions could have been evolutionarily adaptive in mammalian mother–infant interactions. The findings have implications for parenting practices in developmentally normal populations. In addition, we propose that infants’ physiological response may be useful in clinical assessments as we discuss possible implications on early screening for child psychopathology (e.g., autism spectrum disorders and perinatal brain disorders).

Interacciones entre las madres y sus bebés prematuros durante el período de hospitalización

“…It has also been described as a facilitator for the development of infant self-regulation, an ability that allows babies to adapt to changes in environmental stimuli (Ferber & Makhoul, 2004). Mothers' need to touch or hold their babies may be related to the existence of sensory mechanisms that induce regulation, such as the effect that affective touching would have on caregivers and the proprioceptive stimuli the babies receive when being held in the arms of their caregivers (Esposito et al, 2013) or when they are held in their arms by their mothers while they walk, stimuli that in combination decrease crying and their heart rate (Esposito et al, 2015). Through the mothers' narratives, we observed that they tend to touch certain parts of the body of their babies when they are in the incubator such as the hands, feet, face, and head.…”

Theory of Mind: Towards an Evolutionary Theory

“…The new state of mind could best be described as a deep tranquilization or hypnotic trance. Thus, it seems as though evolution has reused the stereotypic behavior of prey, as they are carried away in their captor's jaws, in the service of childrearing (Prestrude 1977;Brewster and Leon 1980;Webster et al 1981;Meyer et al 1984;Yoshida et al 2013;Esposito et al 2015). 8 Comparable reactions have been observed in human infants that are posturally inverted and rhythmically stimulated (Peiper 1963;Krojanker 1969;Vrugt and Pederson 1973).…”

“…Teitelbaum et al 1998;Teitelbaum et al 2004;Esposito 2011). A particularly interesting expression of this is that autistic children have difficulties in adjusting their bodies to being held and carried, often resulting in comments by their parents such as "I feel as if I am holding a stone" or "It does not feel like a baby, more like a sack of flour" (Esposito et al 2009(Esposito et al , 2015. This rigidity and tension is indicative of a postural dysregulation.…”

“…Peiper 1963;Krojanker 1969;Vrugt and Pederson 1973;Yoshida et al 2013;Esposito et al 2015). 43 This relaxed mode of being, mostly spent in a supine position, plays an important role in their subsequent cognitive development.…”

How Can I Make My Younger Sibling Stop Crying?

“…B. An experimenter uses his fingers to mimic the way the mother carries the pup, both during holding (blue) and carrying (red) (figure extracted from Esposito et al [7]). Because the mouse pups and the human babies reacted similarly, researchers began to use mice to better understand people.…”