THE DIMENSIONS OF THE BRAIN OF PRESENCE
Mapping a new territory
Social neuroscience explores the biological and neural mechanisms underlying our social behaviors and relationships — from empathy to cooperation, from attachment to competition. At the heart of this field, a dominant model has established itself: the Social Brain, defined as the set of brain regions involved in social cognition. This model has profoundly transformed neuroscience by showing that our emotions, decisions, and behaviors depend on others. But it rests on an implicit assumption: sociality begins with interaction — understanding others, interpreting their intentions, communicating, cooperating.
The Brain of Presence project starts from a question this model leaves open: what if sociality began before interaction itself?
Because even before perceiving, interpreting, or cooperating, the brain is already responding to a more fundamental question:
"Is there someone there?"
Not a question that is resolved once, but an estimate that is continuously reformulated, with varying degrees of certainty.
Presence is not a simple context in which the brain functions. It is a continuous condition in which it develops, organizes itself, and sometimes repairs itself. The Brain of Presence does not challenge the social brain — it explores what happens before, and why that "before" changes everything.
The pages that follow explore five broad dimensions of this question.
1. The biological and evolutionary dimension
What if presence were a property of living things?
Sensitivity to the presence of others predates the brain itself. Certain bacteria detect the density of their fellow organisms and collectively modify their behavior in response — this is quorum sensing, described by Bonnie Bassler and her colleagues, which constitutes one of the oldest forms of response to the presence of others. Analogous mechanisms are found in insects, fish, birds, and mammals. In humans, James Coan has shown with Social Baseline Theory that the brain treats the presence of others as its default condition for functioning: being alone is an energy cost, being accompanied an economy. The brain did not invent sensitivity to presence — it inherited it, and has carried it to an unprecedented level of complexity.
→ Biological and evolutionary dimension
2. The phenomenological dimension
How is presence experienced?
Before being an object of science, presence is an experience. Some people calm us; others sharpen our vigilance. We don't think in the same way alone or when being observed — an effect documented as early as 1898 by Norman Triplett, and revisited since under the name of social facilitation. But presence isn't always observed: most often, it is sensed. A sound in the next room, a barely glimpsed silhouette, the diffuse feeling of being watched without any certainty — these ordinary situations, where presence remains uncertain, may be more revealing than those where it is immediately obvious. But the phenomenology of presence goes further: Maurice Merleau-Ponty had sensed that the perception of others is not an intellectual inference, but an immediate, bodily, pre-reflective grasp. And certain absences continue to act long after the other has left — something that the clinical experience of grief and trauma illustrates every day. This dimension explores what presence changes in human experience itself.
3. The developmental dimension
How does presence build the human being?
The human brain never develops alone. From the very first moments of life, it is built in a world populated by faces, voices, gazes, and presences. The work of John Bowlby on attachment, extended by that of Mary Ainsworth, Allan Schore, and many researchers in developmental neuroscience, shows that the quality of early presences directly contributes to the organization of the nervous system, the regulation of stress, the development of emotional and social capacities, and the construction of the sense of self. Studies on children from Romanian orphanages provided a tragic demonstration of what the absence of stable human presence can produce on a developing brain. Conversely, a sufficiently attentive, predictable, and secure presence constitutes the environment in which the child progressively learns to feel safe, to understand themselves, and to understand others. To explore this dimension is to explore the way in which the human brain is built in presence.
4. The clinical dimension
What happens when presence systems are disrupted?
Presence does not only contribute to development — its absence, incoherence, or threatening character leaves lasting traces. Stephen Porges' polyvagal theory offers a framework for understanding how the nervous system continuously evaluates the safety or danger of another's presence — what he calls neuroception.
This continuous evaluation can become dysregulated in several ways. The system may under-weight a signal of presence that is nonetheless real — a possible avenue for understanding certain experiences of derealization. It may, conversely, over-weight an insufficient signal — an avenue for hypervigilance and certain persecutory experiences. Or it may weight signals in a chronically biased way, as in social anxiety. These avenues do not constitute a separate development from the theoretical model: they are its direct clinical extension.
Trauma, anxiety, depression, and dissociation can be reread as disruptions of these systems for detecting and responding to presence. This reading opens concrete therapeutic perspectives: from EMDR to somatic approaches, it is often the conditions of presence within the therapeutic relationship that make transformation possible.
5. The civilizational dimension
What becomes of the human being when the forms of presence are transformed?
Human beings have never been so connected. And yet John Cacioppo devoted a significant part of his research to showing that subjective loneliness — distinct from objective isolation — constitutes a health risk factor comparable to smoking. Digital technologies, telepresence, and artificial intelligence are profoundly changing the conditions in which we meet, learn, and care for one another. Humanoid robots elicit neural responses close to those induced by human presence — with real effects on cognition and behavior, as research from the CNRS on robotic social facilitation has shown. Understanding presence thus becomes a way of reading the most decisive transformations of our societies.
The Social Brain explains how we interact with others.
The Brain of Presence seeks to explain that the brain is already social before any interaction.