Those who feel lonely often have the feeling that others do not understand them. A study now confirms this impression using brain scans: While test subjects who feel socially involved all showed similar neural responses to a series of videos, the reactions of lonely subjects differed significantly. It did not matter whether the people who reported feelings of loneliness are actually objectively lonely. The new findings could also explain why some sufferers feel alone when surrounded by people.
Many people have been complaining about loneliness, and not just since the pandemic-related lockdowns and distance requirements. The feeling of loneliness does not necessarily go hand in hand with social isolation. While some people consciously look for phases of solitude and feel good about it, others feel lonely when they are surrounded by other people. The triggers often include the impression of being different from the others and not being understood by them.
Different brain reactions
A team led by Elisa Baek from the University of California in Los Angeles has now shown that the brain of lonely people actually works differently than that of their non-lonely peers. For the study, the researchers showed 66 first-year students a series of short video clips – including excerpts from comedies, documentaries, party scenes and sentimental music videos. In the meantime, they measured the activity in various brain regions of the subjects using functional magnetic resonance imaging (fMRI). They then had the participants fill out a standardized questionnaire on the subject of loneliness, which surveys both subjectively felt and objective loneliness. All experiments took place at the beginning of the 2019/20 winter semester, i.e. before the COVID-19 pandemic.
The result: “We found that non-lonely individuals were very similar in their neuronal responses, while lonely individuals were remarkably dissimilar to each other and to their non-lonely peers,” report Baek and her team. The differences mainly affected the so-called default mode network in the brain, also known as the resting state network. These are areas of the brain that are most active when we are resting, daydreaming, or dealing with ourselves. Previous studies have also shown that individuals who have similar resting state network activity perceive and interpret stories and events in similar ways.
Everyone is lonely differently
“Our results are consistent with recent assumptions that the default mode network is a ‘meaningful’ network that combines external information about an individual’s environment with existing internal information about past memories and knowledge,” explains the research team. Differences were also found in areas of the reward system such as the nucleus accumbens. “Thus, it could be that lonely individuals find different aspects of situations valuable than their peers, perhaps due to differences in their preferences, expectations, and/or memories, which in turn may affect the way they perceive and interpret stimuli.” ”
According to Baek and her team, this could lead to a reinforcing feedback loop: “When lonely people perceive themselves as different from their peers, this can lead to further challenges in building social relationships and increase loneliness,” they explain. This fits in with the observation that many of the test subjects stated that they felt subjectively lonely, even though they often spent time with friends. “This suggests that our results are not just a consequence of lonely individuals having fewer friends,” the authors write. “Instead, we observed that individuals with high levels of loneliness—regardless of their number of objective social connections—were more likely to exhibit unique neural responses.”
Whether the feeling of loneliness changes processing in the brain or whether altered neuronal processing increases the risk of loneliness cannot be derived from the current study. In future work, the team intends to investigate this question using longitudinal studies, in which the same people are observed over a longer period of time. The researchers also want to include people of other age groups in their studies.
Source: Elisa Baek (University of California, Los Angeles) et al., Psychological Science, doi: 10.1177/09567976221145316