BY Franklyn Sills

The Fulcrum, Issue 95 May 2025

The second article in the series explores infant neurology and the roles that mirror neurons and polyvagal theory play in shaping a baby’s relational responses to others and the world around them.

Babies’ Ability to Attune and Respond to Caregivers

Babies directly attune to the caregiver’s presence, their relational world and outer environment as direct felt-experience. It is thus important to explore this process of attunement and response as we orient to the prenate and infant’s relational world. Researchers are still working out the basic neurological processes involved in felt-experience and felt knowing of both our inner states and the states of others. I am offering the best synthesis here that I can at this time and would like to thank Dr. Daniel Siegel for his writings in these areas.¹ ²

The basic idea is that, as babies sense the actions and intentions of others around them, specialised neurons called mirror neurons come into play. These are the starting point for a complex matrix of interrelated neurological responses, which I would like to describe and directly relate to babies’ experience.

Researchers discovered and named mirror neurons in the 1980s and 1990s. In neurological research with monkeys, Giacomo Rizzolatti and his team of researchers discovered that, as the monkeys perceived significant actions of those in their environment, particular cortical neurons fired in their brain. The neurons seemed to be mirroring the actions of others and preparing the monkey to perform similar actions – acting as a bridge between what is perceived and a mirroring motor response to significant experience.^{3 4 5}

Later researchers related these findings to human experience and extended this territory to include early attachment processes and the ability to attune to and empathise with others.⁶

Beyond mirroring and imitating the behaviour of others, mirror neurons also help us sense, feel, reflect, predict and respond to the intentional actions and states of other people, especially significant others.

This is obviously critical for a baby’s relational experience and the basis for their response to  the relational process and caregiver intentions and actions. It is clearly also the felt starting  point for both self/ego formation and attachment processes. The information goes to various  areas of the baby’s cortex and, most tellingly, is directed downward into the body. The  perceptual input of others – especially mother’s and caregivers’ intentions and actions – then becomes a felt-body experience, which helps the baby to sense and know very directly the  actions, states and intentions of others. These feeling states are relayed back upward to the  prefrontal cortex, which mediates present-time awareness, and then becomes felt-knowing – both of the baby’s internal states and the actions and states of others. These then become  the ground for the baby’s internal organisation and responses to their external relational  world. Let’s tease out some of the basic neurological dynamics of this process in terms of  everyday experience.

One of the prime functions of our brain is to predict and prepare us for the outcomes of  experience. As we perceive relationally relevant experience, our mirror neurons fire and  interact with the superior temporal cortex. The temporal lobe in general, especially the  temporal cortex and hippocampus, gives a historical context to present experience. It helps  us predict and appropriately respond to the outcomes of relational experience. Thus, present  time experience is contextualised relative to past history. Current relational process is  experienced through the filters of our past and this may lead us to misinterpret the relational  intentions of others. We will come back to this important territory later.

As mirror neurons resonate with current experience, perceptual information is sent to the  motor areas of the frontal cortex, which primes us for motor responses to perceptual  experience, and to the anterior insula, which is involved in awareness of our inner states  (interoception) and the contextualisation and processing of our emotional experience. The  information continues to descend through the limbic system and brain stem into the body.  Our perception of others’ intentions, actions and inner states is now present as sensation,  feeling-tone and emotional qualities in our viscera and soma. This is called internal  simulation – our body resonates with our external experience and inner feeling states result.

Next, these sensations and feeling-tones are relayed back up to the insula and prefrontal  cortex via nerves called interoceptors. This gives us a felt-perception of our inner states.  Internal felt-information from muscles, viscera, nociceptors (pain receptors), and facial  expressions goes through the spinal cord to the brain stem, hypothalamus, parietal cortex,  insula, anterior cingulate cortex and prefrontal cortex. A complex of responses then occurs.

The hypothalamus – the master regulator of our interior world – responds to these inner-feeling states via changes in hormones and hormone regulation. The parietal area is believed to be involved in self-awareness and self-identity – hence, as felt-information states ascend to the parietal area, our self-view and identity also become a felt-experience! This is pivotal in  the baby’s developing sense of selfhood and the unfolding of attachment processes.

The anterior cingulate cortex and insula are involved in our awareness of these inner states  and the processing of sensory information into an emotionally relevant context, which is  pivotal in affect regulation. The totality of all of this is sent to the right prefrontal cortex – the  mediator of present-time awareness – and a direct felt-knowing of our relational world is  experienced. Thus when we perceive and attune to another, we are actually attuning to our  own inner states and feeling-tones. This is very important to understand in terms of a baby’s  direct experience of its outer and inner world. All interoceptors in the body go to the right  prefrontal cortex – babies are right-brain, present time beings and thus have the ability to  sense directly their inner felt-world via their right-brain orientation holistically, which is not  sensed as separate from their outer experience of caregivers or significant events.

In summary, mirror neurons resonate with the intentions of relational others, interact with the cortex and relay signals to the viscera about the caregiver’s presence and actions. This felt  resonance is then directed back to the prefrontal cortex and becomes direct felt-experience. When felt-experience is perceived via the right prefrontal cortex, another important process is initiated. The prefrontal cortex, along with the anterior cingulate cortex, relates current  experience to our historical map of relationship mediated by the temporal lobe. We then have a holistic picture of our present relational experience held in the context of history and time. The baby thus builds an inner picture of its world based on direct felt-experience, which is  pretty much in place by three years of age. This process then sets the stage for how we  experience others, attribute states to them and predict possible outcomes of relational  interchange. It also helps both baby and adult read the inner states of others, empathise with  their emotions and life experiences, sense their intentions and predict the outcomes of  experience. This is both the ground for early personality formation and attachment process – and for our experience of relationship throughout life.

All of this is critical in our lives on many levels. Very early in life, it sets the stage for our later  response to intimate others, to caregiving, to friends and family, indeed to all those we meet  in our relational world. There is, however, a caveat to be aware of. From our earliest  experience of caregiving, mediated largely through the neurology discussed above, we get a  felt-experience of our inner and outer world and begin to form a self-system with its  attachment processes. When we experience difficult, intrusive or avoidant caregivers, our  nervous system will express protective responses that may become ingrained and become the root of what is known as developmental trauma. This early conditioning will colour our  later relational experience and we may make the felt-mistake of attributing past relational  pain to current relational experience. We may see/sense danger when none exists, read  others’ intentions and inner states through the filters of these past experiences and act  inappropriately toward others. In the extreme, if an overly defended, insecurely attached  personality system evolved out of early relational pain and/or confusion, current relational  processes may be misread and defensive ego processes engage when there is no real  relational danger present.

Babies’ Neurology: Present-time Social Beings

The infant’s world is a holistic experience, where every sense is present all at once—seeing,  hearing, smelling, tasting, touching, feelings and emotions. Thus, the emotional world of the  infant is immediate, without the ability to regulate responses or feelings and without the ability  to contextualise and differentiate its experience or to understand whose feeling is whose. What is sensed “out there” is experienced as “in me.” ^{7 8}

Babies are right-brain beings oriented to holistic awareness -the ability to perceive everything all at once.

Babies are also social nervous system beings. Researcher Stephen Porges, who has developed the polyvagal theory of the nervous system, has reclassified the autonomic  nervous system, which is usually discussed in terms of the sympathetic and parasympathetic systems, into a hierarchical system with three aspects—the social, sympathetic and parasympathetic systems.⁹ This makes much more sense of the actual nuclei and nerves involved and is pivotal in understanding a baby’s response to its relational world.  Porges realised that the classic parasympathetic nervous system has two different sets of  nuclei, which have very different functions. The dorsal motor nucleus sends fibres to the  viscera and has classic parasympathetic functions. The nucleus ambiguus, however, has  fibres that go to the heart and to five different cranial nerves, which have the function of  orienting and social engagement. If the relational field is sensed as safe and receptive,  babies are very much present-time, social nervous system beings.

The social nervous system is mediated by nuclei in the brain stem, which provide nerve  innervation to neck muscles, to the baby’s ears, eyes, mouth, heart and lungs. They allow the baby to orient and respond to a caregiver’s presence and to make its needs known via facial  expression and vocalisation – via social communication and the communication of feelings and inner states. They allow the baby’s heart and mind to regularise and relate to social interaction. If needs are not met at this level, if the baby feels unseen, abandoned or unreceived, its nervous system may shift to a sympathetic response with shouting, crying and anger. Its last defensive response, if needs are still parasympathetic state of withdrawal, dissociation and freeze. These early experiences and inner states set the tone for personality tendencies and defensive processes later in life.

References

1. Siegel, D. (2007) The Mindful Brain. W.W. Norton.
2. Siegel, D. (2010) The Mindful Therapist. W. W. Norton.
3. Rizzolatti, G., Fadiga, L., Fogas, L., and Gallese, V. (1996) Premotor Cortex and the Recognition of Motor Actions, Cognitive Brain Research, 3:131–141.
4. Rizzolatti, G., and Craighero, L. (2004) e Mirror-Neuron System. Annual Review of Neuroscience 27:169–192.
5. Rizzolatti, G., and Sinigaglia, C. (2008) Mirrors in Our Brain: How Our Minds Share Actions and Emotions. Oxford University Press.
6. Iacoboni, M. (2008) Mirroring People. Farrar, Straus and Giroux.
7. Schore, A (2001a) Effects of a Secure Attachment Relationship on Right Brain Development and Infant Mental Health, Infant Mental Health Journal Vol. 22 (1-2) 7-66 (2001).
8. Schore, A (2001b) The Effects of Early Relational Trauma on Right Brain Development, Affect Regulation and Infant Mental Health, Infant Mental Health Journal vol. 22 (1-2) 201-69 (2001).
9. Porges, S.W. (2011)The Polyvagal Theory: Neurophysiological Foundations of Emotions, Attachment, Communication, and Self-regulation, W. W. Norton & Co

The opinions expressed in this article are those of the author and do not necessarily reflect the viewpoints of the CSTA.