How Loneliness Affects the Brain – Conversations to Remember

It is human nature to want to connect and socialize with others. Researchers infer this trend initially emerged from our ancestors, who strictly relied on one another for safety, food, protection, and social connection. This “strength in numbers” mentality is what led many of these early civilizations to thrive in life-threatening situations, such as extreme climate changes. These social constructs were especially unique, because everyone had to cooperate in order for the group to properly function. Those who engaged in social loafing and/or preferred being alone were unlikely to be as successful, as they could not rely on others for support and guidance.

A classic example of this distinction in performance is how these groups would hunt for food. If all members of a group worked together on a hunting mission, they would have an easier time successfully catching prey. This is because they established a sense of trust and reliance on one another as they created this allegiance. However, if another group had members who did not put in enough effort to guarantee everyone’s well-being, were deceitful, and/or acted on their own, they would run the risk of losing their prey or possibly dying, especially if the animal overpowered them. A possible explanation for this is that these individuals could not confidently perform their tasks if they were burdened with other responsibilities, especially if they had unreliable group members. Consequently, this could have served as a distraction and delayed their productivity in carrying out their assigned duties.

To further understand the relationship between well-being and social connectedness, scientists used neuroimaging equipment to examine this association in the brain. This approach led anthropologist Robin Dunbar to coin the “Social Brain Hypothesis,” which explains how the brain, more specifically the neocortex, grows to maintain our social relationships. The neocortex is a structure that encapsulates the majority of the brain and is responsible for all cognitive functions. This finding is what differentiates the human brain’s size from other species’ as they do not engage in the same, complex relationships we do, such as friendships and romantic partnerships. For that reason, the bigger our social networks become, the bigger our brains grow in size to accommodate these new peer connections.

Since the brain benefits from social interactions, scientists investigated how loneliness can impact its neuroconnections and structures, and who is most affected by it. Loneliness is characterized by feelings of emotional and physical pain due to isolation from others in social environments. Simply put, when an individual’s desire to engage with others is not met, this may cause them to feel unwanted. This sensation is so common that the NIH reports that 60% of Americans report feelings of loneliness. This shows how crucial it is to better understand loneliness.

If left unmanaged, loneliness can lead to higher rates of anxiety, fear of judgment, anger, and sleep disturbances. This is because the brain perceives loneliness similarly to physical pain. Neuroscientists tested this theory by using functional magnetic resonance imaging (fMRI) to measure their participants’ brain activity in their affective neuroscience research. There, they discovered that the anterior insular cortex (AIC) and the dorsal anterior cingulate cortex (dACC) are both involved in processing pain and social rejection. In other words, being rejected can provoke feelings similar to being physically injured. The literature suggests this is because both AIC and dACC are found within the limbic system and have connections to the amygdala, which is a structure within the brain responsible for controlling and processing emotions.

Another brain structure that can be negatively affected by loneliness is the hippocampus, which is responsible for our spatial memory. When we are under stress, the brain may respond by changing its shape through neuroplasticity. It does this by shrinking itself due to a decrease in neurogenesis (i.e., new cell turnover) in high intensity situations. For this reason, cognitive decline, rapid brain aging, and dementia are strongly correlated with loneliness if the individual experiences prolonged periods of stress and memory impairments.

These findings demonstrate how crucial it is to find interventions that can diminish the effects of loneliness. Current studies suggest that individuals learn how to be comfortable within their own space by engaging in activities that bring them joy. The goal is to boost their self-esteem as they learn to be more adventurous and take on these new tasks. One example of this could be self-care, which is a commonly overlooked strategy that possesses many positive rewards for its users. Self-care promotes the release of dopamine and serotonin neurotransmitters in the brain, which may help us feel better about ourselves and put our minds at ease when we engage in enjoyable activities. Consequently, this can be beneficial in canceling out the negative effects of loneliness, such as elevated stress levels.

Additional recommendations include reaching out to others and making new social connections. Such a practice can make us feel more comfortable communicating with strangers and building our network. It is important to gradually engage in this process, as it may take time to get close to others and build strong relationships. Furthermore, we should not compare our achievements to others; this can deter our motivation to be more social if we compare ourselves to those who already have the relationships we yearn for.

By better understanding loneliness and its neurological impacts on the brain, we can learn how to best address it. In doing so, rates of loneliness may decrease as we let others know we care for them and that they are not alone.

Sources: