The Human Brain and the Limits of Social Relationships

The human brain is the most energy-intensive organ in our body. It consumes about 20% of our total energy and, compared to other animals, makes up a disproportionately large part of the body mass. A leading theory suggests that our neuronal networks primarily evolved to regulate complex social relationships. Although the brain accounts for only about 2% of body weight, about three-quarters of it is devoted to the neocortex, the region responsible for memory, language, problem-solving, and self-awareness. These abilities enable us to navigate complex social dynamics in families, communities, teams, and workplaces. Maintaining a broad social network also contributes to better overall health. However, the cognitive demands associated with maintaining social bonds impose a natural limit on the number of stable relationships we can maintain.