Psychology researchers at the University of Southern California Dornsife found by comparing brain images that there are significant differences in the brain processing patterns of lonely people compared with those who are not lonely. The Russian writer and philosopher Leo Tolstoy may have been inspired when he wrote the opening sentence of "Anna Karenina": "Happy families are all alike; every unhappy family has its own misfortune."
A study recently published in Psychological Science by the USC Dornsif College of Letters, Arts and Sciences (USCDornsif Research led by an academic at the eCollege of Letters, Arts, and Sciences shows that while people who do not experience loneliness show similar patterns in brain information processing, those who are lonely appear to interpret the world in a way that is very different for each individual.
Numerous studies show that loneliness is detrimental to physical and mental health and is often accompanied by self-reported feelings of not being understood by others. A recent report from the U.S. Surgeon General's Office called loneliness a public health crisis in response to the growing number of adults suffering from it. Even before the COVID-19 pandemic, about half of U.S. adults reported experiencing measurable levels of loneliness.
Loneliness is specific
University of Southern California Dorn While doing postdoctoral research at UCLA, Elisa Baek, an assistant professor of psychology at Seaver, tried to better understand what caused this sense of disconnection and misunderstanding. Using a neuroimaging technique called functional magnetic resonance imaging (fMRI), Baek and her team examined the brains of 66 first-year college students as they watched a series of video clips. The themes of these videos range from sentimental music videos to party scenes and sporting events, providing diverse scenarios for analysis.
Before the scan, participants aged 18 to 21 were asked to fill out the UCLA Loneliness Scale, a survey that measures a person’s subjective feelings of loneliness and social isolation.
Based on the survey results, the researchers divided the participants into two groups: lonely people and "non-lonely people" (people who do not feel lonely). They then used fMRI to scan each participant's brain while they watched the video.
By comparing brain imaging data from the two groups of people, researchers found that lonelier people showed more different and specific brain processing patterns than those who were not lonely.
This finding is significant because it reveals that neural similarity—the extent to which brain activity patterns are similar across individuals—is linked to a shared understanding of the world. This shared understanding is important for building social connections. Not only are people with autism less similar to society's standards for processing the world, but each lonely person is also uniquely different. This uniqueness may further influence feelings of loneliness and lack of social connection.
"We were surprised to find that lonely people were less similar to each other," Baek said. "In fact, they found no common ground with either lonely or non-lonely people, which made it harder for them to connect to society. The 'Anna-Karenina principle' is an apt description of lonely people because they experience loneliness in an idiosyncratic way, rather than in a universally relatable way. "
Loneliness has nothing to do with whether you have friends
So, is the specific treatment of lonely people a cause of loneliness, or is it a result of loneliness?
Researchers observed that people with high levels of loneliness were more likely to have specific brain responses, regardless of the number of friends or social connections they had. This raises the possibility that being around people who view the world differently than oneself may be a risk factor for loneliness, even if a person interacts with them regularly.
Research also suggests that because social connections or disconnections can fluctuate over time, this may affect the extent to which a person processes the world in idiosyncratic ways.
Looking forward, Baek said she is interested in studying people who have friends and are socially active but still feel lonely. In addition, researchers are studying specific situations in which lonely people cope differently. For example, do lonely people show specificity in dealing with emergencies or ambiguous social situations?