Bio-behavioral synchrony promotes the development of conceptualized emotions

Abstract

As adults, we have structured conceptual representations of our emotions that help us to make sense of and regulate our ongoing affective experience. The ability to use emotion concepts is critical to make predictions about the world and choose appropriate action, such as 'I am afraid, and going to run away' or 'I am hungry and going to eat'. Thus, emotion concepts have an important role in helping us maintain our ongoing physiological balance, or allostasis. We will suggest here that infants can learn emotion concepts for the purpose of allostasis regulation, and that conceptualization is key component in emotional development. Moreover, we will suggest that social dyads facilitate concept learning because of a robust evolutionary feature seen in newborns of social species: they cannot survive alone and depend on conspecifics for allostasis regulation. Such social dependency creates a robust driving force for social learning of emotion concepts, and makes the social dyad, which is designed to regulate the infant's allostasis, an optimal medium for concept learning. In line with that, we will review evidence showing that the neural reference space for emotion overlaps with neural circuits that support allostasis (striatum, amygdala, and hypothalamus) and conceptualization (medial prefrontal cortex, posterior cingulate cortex), and that their developmental trajectories are interrelated, and depend on synchronous social care.

Figure 1. A dyadic continuum of emotion development

Infants’ developmental milestones are contingent on caregiver provisioning of allostasis regulation and language use. As caregivers regulate the infants’ allostasis, infants gain experience in the rudimentary social skill of synchrony. Thereafter, as attention develops [53], infants learn to share their attention with the caretaker [54], and to synchronize conceptual knowledge. Synchronous parenting fosters the child’s ability to use concepts *[55], and parental use of mental state language promote children to label their own emotions [42] and later to recognize and represent other people’s mental states [42, 43, 46]. Children rely on the social conditioning between emotion concepts and allostasis for the development of social cognition, as they learn to use emotion concepts for understanding and regulating other people’s allostasis. The color gradient represents the development of concepts; darker color indicates the infant’s growing ability to represent concepts and therefore engage in self-regulation. Synchronous caregivers carefully adjust their input per the infant’s developmental stage.

Figure 2. Neural circuits supporting allostasis and conceptualization associate in the human brain to support multiple mental experiences, including emotion

A) A neural model for allostasis (yellow) and conceptualization (blue). The amygdala, nucleus accumbens (NAcc), hypothalamus and connecting pituitary secretory gland are involved in allostasis regulation [6]. The hypothalamus-pituitary endocrine system is a brain-body feedback pathway, which regulates the adrenal gland (via the HPA axis), but also gonadal and thyroid function, altogether controlling multiple allostatic processes including growth, reproduction, immunity, stress and metabolism [68]. The medial prefrontal cortex (mPFC) and posterior cingulate cortex (PCC) have been shown to be involved in humans’ mental ability to hold and use internal representations of concepts [62, 69]. B) In humans, these regions are intrinsically connected, forming a neural network [63] that associates limbic circuits (in yellow) with cortical circuits (in blue), potentially demonstrating a functional association between allostasis and conceptualization. Neural function in this circuitry has been associated with different experiences, including emotion **[70], social functioning [71] and synchronous bonding *[64].