The Social Brain Hypothesis

The social brain hypothesis states that human brains evolved and became bigger in order to be more social, not the other way around. Furthermore, the theory states that increasing the capacity for communication about a wide range of subjects was the only reason that brains grew.

The Social Brain Hypothesis

To bring more clarity and expand on the prior section, the social brain hypothesis states that human brains evolved and became bigger in order to be more social, not the other way around. Furthermore, the theory states that increasing the capacity for communication about a wide range of subjects was the only reason that brains grew.

British professor of anthropology and evolutionary psychology Robin Dunbar observed that the size of a species’ social group was the most accurate predictor of brain size—specifically, the outermost brain layer known as the neocortex. This discovery led to the social brain theory.

Scientists believe that the first species with brains on the scale of modern humans—known as Homo heidelbergenesis—originally appeared some 600,000 to 700,000 years ago in Africa. These ancestors to Homo sapiens are also thought to be the first hominids who buried their dead, built central campsites, and utilized a division of labor where they worked together to hunt more effectively. This is no coincidence.

The reasoning behind the social brain hypothesis is that primates have unusually large brains for their body sizes relative to all other vertebrates—a result of needing to manage unusually complex social systems. In other words, in order for society to grow and thrive, the brain needed to evolve to cope with the cognitive demands of being social.

As complex social behaviors limit the sizes of our social groups, there is emerging evidence that shows the evolutionary process has favored individuals with the brain architecture most suited to performing and further developing those social behaviors. Interestingly, the main factor that distinguishes human brains from those of other primates is the size of the aforementioned neocortex—the part of the brain comprising many of the brain areas involved in complex social cognition.

These functions include conscious thought, language, behavioral and emotional regulation, as well as empathy and the theory of mind—the thing that enables humans to understand the feelings and intentions of others.

What does all of this mean?

Humans, as a species, are endowed with a “social brain,” which essentially biologically hard-wires us to interact with each other. Living a life of isolation is correlated with higher risk of loneliness and depression because it requires fighting 600,000–700,000 years of evolution compelling us to socialize. We need to be around others for our mental health, no matter our temperament or personality type.

The Effects of Loneliness

And what about the other side, when we are prevented from indulging our social brains? Social status and success are not mere matters of vanity or self-confidence, but rather crucial factors in our overall well-being. In fact, a lack of adequate social interaction or exposure can have very real consequences on our health—mental and even physical. Loneliness can, quite literally, be lethal. I’s not just a matter of cliché: there is scientific and evidence-based research behind this unfortunate fact.

The UCLA Loneliness Scale, a standard American questionnaire on loneliness, uses twenty questions to determine how often individuals experience feelings of close connection with others. The results indicated that as much as 30 percent of the total American population feels socially isolated and lonely at any given time.

That 30 percent figure is staggering when considering the implications of such loneliness on the health of some 95 million plus Americans. Loneliness varies widely with age but is especially detrimental for the elderly, as it can expedite the process of declining faculties and thus lead to earlier loss of life.

Naturally, you might be thinking that loneliness is a significantly bigger problem among the elderly than the rest of the population because the members of an older person’s social circle are more likely to have passed away as they all age. But it turns out that loneliness is also pervasive among middle-aged and young people.

A 2010 survey published by the AARP showed that greater than 33 percent of adults aged forty-five and over report being chronically lonely, meaning that their feelings of loneliness have been consistent over a long period of time. This is even more alarming when you consider that when the same survey was conducted in 2000, only 20 percent of participants reported chronic loneliness. As approximately 10,000 Baby Boomers retire every day, that number is likely to grow considerably higher by 2020.

Researchers at the University of Chicago conducted a study over a five-year time frame that measured the correlation between loneliness and future depression. They found that people who had reported being lonely at the beginning of the study had a much greater tendency to report depression near the end of the study. In fact, the study found something truly surprising—people who were lonely at the beginning of the study were actually more likely to report feeling depressed at the end of the study than those who had been depressed to begin with. In other words, loneliness was a more common precedent for depression than actual depression was, and the situation is only getting worse.

It is quite surprising that despite the promised global connectivity of our contemporary digital lives, the research captures the spreading of loneliness in society. There are studies in progress specifically interested in the relationship between online socialization and loneliness. This field of study will only continue to become more interesting as social media becomes a more significant part of our social life.

Many studies have already shown that high social media use has a negative effect on happiness and social fulfillment. At this point, social networks have grown too big to simply be phased out, so society will have to find ways to use those networks in a more positive manner if loneliness and depression are to be curbed before reaching epidemic levels—if they haven’t already.

Brain structure and functionality change over thousands of years, and a large percentage of our modern communication methods are simply too new to be fully understood in relation to the social brain. The telephone has been around for just over a century, and instant messaging or texting for far less time than that.

Is it possible that communicating predominantly through computers and phones instead of face-to-face simply doesn’t fill our evolved need for socializing? Or perhaps the rise in loneliness and feelings of isolation isn’t a direct result of social networks and instant messaging. Could it be an outcome of not understanding how to use technologies in a healthy manner? Or is it that the human brain is physiologically unable to keep up in terms of evolutionary adaptation?

These questions are still waiting to be examined in deeper studies. In the meantime, it’s important for all of us to be mindful of how various levels of technology, and specifically social media use, impact our health and emotional well-being. If chronic loneliness ever becomes an issue for you, consider that perhaps you are not getting enough face-to-face interaction to meet your biological and evolutionary needs.

Health, in all its aspects, implies achieving balance. There can’t be too little or too much, only a certain extent that we can consider healthy social interaction. Hyper-socialization in the social media can also cause strain. What can we say then is a healthy dose of socialization?