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The Social Brain

The Social Brain

Medicine and Science in An Interconnected World

In 1977 George Engel, a psychiatrist, introduced a concept that shifted the medical model away from a strict focus on pathology toward a more nuanced and complex formulation of human illness and health: the biopsychosocial model. What this model promotes it a consideration of the multiple factors that influence a person’s health and well-being, including biological, psychological, and social factors.

Increasingly, since the advent of this idea, healthcare practitioners are moving away from the strict treatment of isolated symptoms and exploring how things like lifestyle, diet, relationship, beliefs, and even the way a person sits while driving a car can impact health. For example, a patient reporting an upset stomach may indicate that the person has contracted a parasite or some kind of infection. But a stomachache may also be a result of too much stress on the job or the outcome of an unresolved fight with a best friend. Within the biopsychosocial model, all of these factors would be examined before a treatment plan would be implemented. This model also exemplifies how influenced we are, as individuals, by those around us: family, friends, colleagues, and even consequential strangers. Rather than being static, isolated bodies that develop disease, the biopsychosocial model focuses on interconnectivity, multiple pathways to both disease and health, and the dynamic nature of human experience. Within this new worldview of medicine, scientific research has demonstrated that our brains are biopsychosocial organs and wire us to those around us into an ever-evolving web of social relations. Our social brains are wired for connection and social interaction.

Neuroscience: The Frontier of the Brain and Mind

At the same time that shifts in the medical model were moving our concepts away from a strict disease model toward focus on prevention and well-being, immense strides in technology enabled medical experts, biologists, neurologists, and social scientists greater access to the study of the brain. During the first half of the twentieth century, in the early years of psychology, the field most concerned with human behavior, experts in both research and clinical practice relied almost exclusively on the concept of behaviorism to explain how and why humans do…virtually every action in life. In short, behaviorism posits that human behavior is a series of inputs and outputs, or stimuli and responses (known as conditioning). Within a behavioral psychological model, external forces control behavior and free will does not exist. This form of psychology is also almost exclusively focused on the actions and reactions of the individual, rather than the complex interplay of people in relationship. Additionally, during the heyday of behaviorism “the cognitive system itself (the human brain) was viewed as a black box, the internal states of which are not amenable to scientific description or explanation” (Held, Knauff, Vosgerau, 2006, pp. 6-7). Thus, within this model, humans are viewed as isolated reactors to external stimuli with predictable patterns of behavior based upon patterns of specific conditioning. The concept of mind, or consciousness, played no role in the experimental side of psychology and was left to psychotherapy, philosophy and religion. In addition, in this model, friendship was generally not an area of focus in the research and left almost exclusively to the sociologists to understand from the perspective of group behaviors and the needs of the collective. Only in the past few decades, as will be explored below, has friendship begun to be understood at the level of the individual, including the ways we choose our friends and the ways in which we remain connected to those whom we call friend.

In the middle of the twentieth century, researchers in psychology made a radical departure from these earlier roots in behaviorism via the cognitive turn, or a movement toward an understanding of the functions of the brain and the brain’s impact on human behavior (Held, Knauff, Vosgerau, 2006). This turn brought about the age of cognitive science. This interdisciplinary field encompasses theory, research, and practice from disciplines as disparate as psychology, neuroscience, philosophy, and computer science (including artificial intelligence). Within this developing field, technologies were created in the last hundred years such as the electroencephalogram (or, EEG) and, more recently, functional magnetic resonance imaging (fMRI) and utilized in efforts to understand brain activity to predict or explain human experience as varied as psychopathology to learning processes to empathy. In this new era of cognitive science, the brain is a central player in the story of human experience, but does not stand alone as the center of the human story. Rather, the brain is a vital element in the complex network of the physiology of the human individual, who, in turn, relates to others in the outside world.

According to thought leaders in the fields of neuroscience, cognitive science, and interpersonal neurobiology, we are in the nascent stages of brain research. V. S. Ramachandran (2011), a physician and researcher who directs the Center for Brain and Cognition at the University of San Diego, uses the analogy that brain research right now is at the same stages of discovery as chemistry in the nineteenth century. “We are still groping our way toward the equivalent of the periodic table but are not anywhere near atomic theory” (location 5338). But even though we are in such early days in this research, what we have learned is already profoundly altering the ways that we understand human behavior, human development, and human relationship.

In this new age of brain science, distinctions are made between the brain and the mind. As would be expected, the brain generally refers to the organ itself, consisting of roughly 100 billion neurons, interconnected nerve cells that “talk” to one another in trillions of complex patterns and enable us to function and interact (Ramachandran, 2011). “The number of possible brain states is staggeringly vast; in fact, it easily exceeds the number of elementary particles in the known universe” (Ramachandran, location 541). Thus, even though immense strides have been made in mapping the complex functions of the brain, this research is still in its infancy. Nonetheless, what this early research has demonstrated is that the brain is a relational organ at the center of a larger construct many philosophers, scientists, and clinicians refer to as mind.

Within cognitive science, a discipline known as theory of mind has endeavored to explain and differentiate the physiology of the brain from the more mysterious, yet vital construct of the mind, or the mental capacity to have a sense of self. The term mind is often conflated with the term consciousness. Antonio Damasio (1999), one of the founders of the Brain and Creativity Institute at University of Southern California, poetically describes consciousness:

At its simplest and most basic level, consciousness lets us recognize an irresistible urge to stay alive and develop a concern for the self. At its most complex and elaborate level, consciousness helps us develop a concern for other selves and improve the art of life. (p. 5)

Daniel Siegel (2001), a psychiatrist and Co-Director of the Mindfulness Awareness Research Center at UCLA, coined the term interpersonal neurobiology to describe the interrelated nature of human behavior and interaction and how our connectedness impacts brain function, mind processes and also how brain function impacts our abilities to connect. Through collaborative interdisciplinary research and scholarship, Siegel (2007) has studied how the brain generates the mind. He notes that the mind is “a process that regulates the flow of energy and information” (p. 4).

This is not simply an internal process, however, but an interactive process.

Our human mind is both embodied and relational. Embodied means that the mind involves a flow of energy and information that occurs within the body, including the distributed nervous system we’ll refer to by using the simple term, “brain.” Relational signifies that dimension of the mind involving the flow of energy and information that occurs between people. (Siegel, 2007, pp. 4-5)

As will be explored further below, an individual’s brain/mind is not an isolated event, but a relational entity changing itself constantly while also changing others via interaction and imitation.

The Changing Brain: Evolution, Attachment, and Neuroplasticity

Brain research relies heavily on evolutionary theories and draws from anthropology, linguistics, and evolutionary psychology to explain why the brains of humans are larger and more complex than even our closest primate relative. While, genetically, humans are more similar to primates than not, the human brain is more differentiated in structure than the brain of an ape. Louis Cozolino (2006), a psychotherapist and professor at Pepperdine University, offers a comprehensive explanation of the evolution of the social brain in his book, The Neuroscience of Human Relationship. The generally accepted theory is that human brains became more complex because our social structures have complexified over the hundred million years that we have evolved into contemporary social networks. Evolutionary theory suggests that, since the brain is the seat of learning and memory, it also evolved to produce language, which became a primary human bonding tool. In short, primate colonies, which are also social, rely on behaviors such as grooming to create social bonds and mating rituals to determine social hierarchy. But grooming is a time-consuming process that requires extended connection to any one individual to accomplish. Anthropologist Robin Dunbar (1992, 1993) suggested that, as group size increased and social groups became more complex, the need for “short-hand” forms of grooming arose and, according to Dunbar, gave rise to gesturing, facial expressions, and, ultimately language, to more efficiently communicate and bond across individuals within larger groups. Thus, the explanation for larger brain size and differentiation of brain function in humans is that a larger brain with more complexity in function is needed to learn and retain these abstracted forms of communication (Dunbar, 1992).

Another novel human experience is that our species’ children are born much less developed than other mammals and require almost constant attention for many years during early development. Evolutionary theory posits that this dependency is significant in the social bonding of groups, since mature humans must cooperate and collaborate for their own safety and well-being as well as protecting the young dependents. Within this social milieu, children rely on caregivers for basic needs such as food, shelter, and comfort. But the caregivers also become the primary people who shape a child’s brain through facial expression, communication, and response to the child’s distress—caregivers become the first, and primary bond in a child’s life.

Psychologists have studied these early childhood bonds for more than half a century. John Bowlby (1969), considered an early pioneer in the development of what is now called attachment theory, led the way in demonstrating the profound impact primary caregivers have on early childhood development of emotion regulation, a sense of safety, and curiosity about the world around them. Recent brain research has offered new insight into why these early relationships are so crucial to well-being over the course of the entire lifespan: bonding with a caregiver impacts the actual wiring of the brain in profound ways. Allan Schore (1994, 2001, 2003), a professor of psychiatry and behavioral sciences at UCLA, has explored the neurobiology of secure attachment, or, in other words, how a close, positive, and nurturing relationship with a primary caregiver impacts the healthy development of the limbic system and the autonomic nervous system in an infant. The limbic system and autonomic nervous system are crucial areas of the brain and nervous system that regulate emotion and responses to stress: these two brain areas are integral to the fight-flight-or-freeze response when threat is posed to the self, either real or imagined.  Additionally, Schore’s (2001) research demonstrates that emotion-regulation and healthy adaptation to social interaction are functions primarily of the right brain. The right area of the brain-and notably the right limbic area—develops rapidly during the first three years of life. Thus a human being’s ability to function effectively later in life under normal as well as stressful circumstances is directly tied to early caregiving, an essential factor for healthy brain development.

Louis Cozolino, mentioned above, along with Daniel Siegel, is a leader in the development of the field of interpersonal neurobiology, or a study of how brain function is impacted by relationship, and also how brain function changes in relationship to others. What his research, as well as the research of many others including Siegel and Schore, is demonstrating is that we are born with a specific genetic makeup (nature) that predisposes us to specific patterns of response based upon the structure of the nervous system and brain. But genetics is only part of the story: interaction with the world around us (nurture) impacts the body’s ability to form proper neural pathways and regulate the nervous system appropriately. In short, both nature and nurture are critical to the formation of the neurobiology of a healthy social brain. As noted above, the optimal state of attachment which enables infants to feel secure in the bond to their caregiver, which, in turn, enable the infant to venture out to explore the world and know that there is a safe haven to which to return. In a recent exploratory study, a researcher demonstrated strong association between secure attachment style and the ability to make close friendships as well as membership in a larger peer group in adolescence (Zimmermann, 2004). Thus, early development of a healthy brain seems to be a key factor in developing and maintaining strong social ties throughout the lifespan.

But early brain development is not the end of the social brain story. The ways in which we interact with the world, whether confident, calm, and engaged, or insecure, anxious, and withdrawn are, indeed, profoundly affected by our experiences in infancy as noted above. Nonetheless, what recent research has demonstrated is that the brain is continuously changing over the course of the entire lifespan. In other words, everything we do, and everyone we meet changes our brains. This ongoing, constant adaptation and development of neural pathways is a phenomenon called neuroplasticity. Until very recently, the commonly-held belief, including among medical and scientific professionals, was that, after the crucial developmental periods of infant brain development described above, the brain was in a static, “finished” state throughout the remainder of life. Over the course of the past decades, however, research has demonstrated that the brain is an incredibly adaptive, complex set of neural networks, comprised of billions of nerve cells. Much of our understanding of the brain’s ability to change has resulted from research on individuals who develop a brain malady or suffer an injury such as head trauma or stroke. By studying the areas of the brain impacted by such injury, scientists have charted a more sophisticated map describing the interaction of neurons, or neural networks that control the entire experience of being alive and sentient. Popular works by V.S. Ramachandran (2011), Oliver Sacks (1998), and Daniel Siegel (2010) have described the way that exceptional cases of brain injury help us to better understand typical brain function. This research has led to a greater understanding of the reciprocal nature of brains interacting with other brains and helps to explain the phenomenon of how individuals continually re-wire their neural pathways.

A Key to the Social Brain: Mirror Neurons

As noted throughout this discussion of the brain and mind, research into the biological correlates of social behavior is still in the very early stages. But one major breakthrough has been made in understanding how we learn from one another and why, according to recent research, we appear to be so deeply interconnected with one another. As social and interdependent beings, humans are natural collaborators: we learn from and protect each other to ensure the overall safety of the social network (Cozolino, 2006). A way that we accomplish cohesion of the social group is through learning from one another. A key way that we learn is through imitation, or by watching the actions of another and then, over time, developing the ability to replicate the same action. Some scientists have coined the term “monkey see, monkey do” to describe this imitative behavior. Recent brain research has uncovered the neurological structures responsible for this phenomenon: mirror neurons.

Two decades ago, in a research lab in Parma, Italy, scientists were conducting research on the neural pathways of primate brains to understand motor response to visual stimuli. The research was seeking to understand what areas of the brain are activated when a primate grasps for food and eats the food. While conducting their experiments, however, they stumbled onto a revolutionary finding. The very same areas that were stimulated when a primate ate something were also stimulated when the primate watched a human eat food as well. One of the lab technicians inadvertently aided in this discovery by eating some nuts in front of one of the lab primates; as the primate watched the technician eat the food, the brain of the primate was stimulated as if the primate was eating the food (Rizzolatti, Fadiga, Gallese, Fogassi, 1996). In other words, the neurons regulating motor control are also involved in watching the actions of others. This discovery is important because it was the first piece of neurobiological evidence that our brains are literally wired to the environment around us: our brains are, in essence, imitating the actions that we see all around us without our bodies replicating the actions. Imitation as a form of learning is a highly evolved function found in primates, especially humans. Human beings can learn an action simply from seeing the action done by others (Rizzolatti & Craighero, 2004). Anyone who has attended a sporting event, or even watched baseball or football on television with an avid group of fans, has seen mirror neurons in action. Spectators will swerve in their seats as a runner rounds the bases or duck heads during a particularly brutal tackle; they are mirroring the motions of the players while transfixed on the action.

One reason why this imitative ability to learn is so important relates back to early childhood development: we begin to imitate the facial expressions of others virtually from birth (Cozolino, 2006). Brain research has demonstrated that social bonding is accomplished through communication, the most rudimentary, and, arguably most important form of which is facial expressions and gestures. Thus, mirror neurons are integral in our ability to form bonds with primary caregivers, and, it is proposed, fosters the necessary secure attachment and emotional attunement for optimal brain development.

Taking the concept of imitation into the emotional realm, mirror neurons appear to be integral brain structures in the human quality of empathy, or the ability to maintain a sense of one’s self while also being able to understand and have an internal mental model of the experience of another.

Imitation facilitates social interactions, increases connectedness and liking, gets people closer to each other, and fosters mutual care. . . .it should follow that good imitators should also be good at recognizing emotions in other people, which in turn may lead to greater empathy. . . . [which] would predict a correlation between the tendency to imitate others and the ability to empathize with them. (Iacaboni, 2009, p. 658).

Marco Iacaboni, a neuroscientist with the UCLA Brain Research Institute and a close colleague of the scientists in Parma who discovered mirror neurons, has done remarkable research linking mirror neurons to imitative and empathetic behaviors. What Iacaboni suggests is that during the evolutionary process, mirror neurons were selected for the very imitative qualities that produce empathy. His argument further posits that mirror neurons solve what scientists call the “problem of other minds,” or the human capacity for intersubjectivity. Thus, these neurons are at the core of our social brain. As noted above, neurobiology and neuroscience are in a stage of infancy. In coming years, research on how mirror neurons are (or are not) activated in online environments will most likely become a central focus, since online social networking is quickly becoming a major part of how many people make and maintain social connection.

Social Ties and Social Intelligence: Practical Understanding of the Social Brain

As noted above, research is in very early phases of uncovering the profound levels of physiological interconnectedness that fosters and maintains social networks. The skills and processes humans develop to maximize this interrelationality have been written about by anthropologists and psychologists who offer some practical application of these cutting edge research findings. Returning back to Robin Dunbar (1992; 1993), the anthropologist who studies language and social group formation, he introduced a hypothesis in the early days of brain research tying the large size of the human brain to social group size. He suggested that due to the size of the neocortex in the human brain, individuals have cognitive capacity to be in stable social relationship with roughly between 150-230 people at any given time. After studying primate social behavior as well as the size of close-knit early human societies, Dunbar concluded that language was a primary tool that enabled people to congregate in communities of this size, because, as noted above, language served as a short-cut or symbolic substitute for much more time-consuming social behaviors like grooming. What this means, is that, on average, we have the memory and cognitive capacity to remember enough about these other people and have enough time to stay in contact (even the yearly holiday card counts as contact in this context) with this many people. In order to maintain relationship, we need to have the capacity to devote mental and emotional bandwidth to those for whom we profess friendship.

With ever-increasing reach of social networking online and the high mobility of many people who may relocate multiple times in a lifetime, this number may seem small. But Dunbar’s number is actually a measure of strong social ties, rather than weaker ties.  As noted in the paper The Mechanics of Friendship (Brooks, 2012), our interpersonal ties vary across a spectrum of closeness and frequency of interaction. Thus, Dunbar’s number may be very useful in determining our close social network, but may not take into account the utility of connections with a wider web of individuals who are professional contacts, experts we may follow on Twitter, and friends of friends of friends all of whom may provide important professional and personal information that improves our lives and well-being, including potential work opportunities and health information.

Beyond sheer numbers of interpersonal connections, brain research has also helped us understand why certain individuals are more successful at social interaction than others. Daniel Goleman (2006), a psychologist and science writer, popularized the concept of social intelligence, or the skills and abilities that enable successful social interaction. Goleman posits several functions of the social brain: “interaction synchrony, the types of empathy, social cognition, interaction skills, and concern for others” (location 5954). But he also suggests that “the ingredients of social intelligence…can be organized into two broad categories: social awareness, what we sense about others—and social facility, what we then do with that awareness” (location 1596). Goleman breaks social awareness down into 4 qualities: primal empathy, attunement, empathic accuracy, and social cognition (location 1599). In short, these qualities mean that a person is able to tune into and read emotional expressions and cues from others and also understand how social interactions function. Social facility includes the abilities of synchrony, self-presentation, influence, and concern (location 1605), the qualities of smoothly and accurately navigating social interaction. While individuals are born with varying levels of these abilities, Goleman and others including Daniel Siegel, believe that through the cultivation of self-awareness and mindfulness, or present-centered attention to our thoughts and feelings, we can improve our social interactions. Siegel popularized the utilization of the insight meditation technique of mindfulness as a process for understanding our own minds and gaining greater ability to regulate our emotions and thoughts in order to become more mindful. He refers to the skill of awareness as “mindsight” or the ability to perceive our own minds and relate to the minds of others. In light of recent research demonstrating the ongoing neuroplasticity of the human brain, individuals learn through imitation (Iacaboni, 2009) and cultivate self-awareness through techniques such as meditation and social mirroring (Siegel, 2010; Iacaboni, 2008), further tightening the links both within the individual brain, and, across brains within a social network.

Curiosity about the mind and the brain are as old as human thought and language, mental qualities some researchers believe developed in homo sapiens 150,000 years ago (Ramachandran, 2011). Ancient wisdom traditions such as Buddhism teach specific practices to calm the mind in an attempt to end human suffering. The Buddhist concept of “monkey mind” illustrates how the unattended mind, or the mind driven by egoic impulse is untamed, restless, and will run wild. As noted above, meditation practices are one technique for utilizing the miraculous neuroplasticity of the brain to foster increased self-awareness, a key component to maximizing the social brain. Ancient belief systems and modern medicine alike have sought understanding of brain function in an attempt to explain human behavior as well as afford empirical evidence and a comprehensive definition to the elusive concept of mind or consciousness. Contemporary strides in neuroscience and social science afford a complex view of the function of the brain and the interrelated nature of the brain, the mind, and human relationship. As noted throughout this exploration of the social brain, we are wired for relationship: our brains are a central element of our ability and desire to relate.


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