Allostasis is the process that maintains homeostasis, or our internal physiological state of equilibrium. In psychological terms, it has been defined as "the core task of all brains to regulate the organism's internal milieu by anticipating needs and preparing to satisfy them before they arise" (Sterling & Laughlin, 2015).
Human infants are dependent on a dedicated caretaker to regulate their physiology. Caretakers feed their infants, and they sing and touch their infants to regulate their temperature, heart rate, sleep, and arousal. With repeated care, infants learn to associate social information with allostasic changes. For example, if the same caretaker is present every time a newborn is fed, the newborn will associate the experience of feeding (digestive sensations, how it feels in their body to have just been fed) with the caretaker's face, smell, and voice. Atzil et al. propose that infants' early allostasis dependency motivates infants to learn social affiliation (whereas other theorists have assumed that social affiliation is innate, not learned during early life within social dyads).
Through social regulation of allostasis, a child acquires social concepts and social competencies. For example, one of the basic competencies children gain is Synchrony, starting from gestation via mother-fetus physiological synchronization and after birth with the same strategy through breast-feeding, singing, etc (Atzil et al, 2018). As infants develop, interpersonal synchrony continues to facilitate their social development, thereby contributing to their social allostatic capacities. In fact, infant-adult brain coupling has been demonstrated to precede social behaviors, such as joint attention, during live interaction (Piazza, Hasenfratz, Hasson, & Lew-Williams, 2019).
The allostatic support of a caregiver is rewarding making social interactions a powerful reinforcement and promotes infant attachment and social bonding. As social creatures, we learn to regulate allostasis of ourselves and others through social conversation. Social dependency for allostasis regulation is an adaptive coevolutionary plan, maximizing social motivation and developmental flexibility in learning culturally relevant knowledge and behavior (Atzil et al, 2018).
A key aspect of allostasis is predictive ability. In order to be effective, allostasis involves the ability to predict what the body might need and to formulate pathways for attaining/satisfying those needs. This predictive quality sets allostasis apart from homeostasis.
In addition to the prediction necessary for allostasis, accurately predicting aspects of one’s social environment helps to support allostasis itself. For example, a hungry child that can form a mental prediction about how crying can influence a caretaker’s behavior will be able to achieve homeostasis because a caregiver will respond to a crying newborn by feeding them. In support of developing this predictive ability, Atzil et al. (2008) propose that a newborn will learn social concepts and stimuli that support allostasis (such as crying to elicit a feeding response from a caregiver) will be learned more quickly than other social concepts that are not predictively related to allostasis.