Researchers at UC San Diego School of Medicine found that specific regions of the brain respond to emotional stimuli related to loneliness and wisdom in opposing ways in a study published Friday.
According to the researchers, loneliness is an important determinant of health. It is associated with considerable physical and mental health risks and increased mortality. Previous studies have also shown that wisdom could serve as a protective factor against loneliness. This inverse relationship between loneliness and wisdom may be based in different brain processes.
"We were interested in how loneliness and wisdom relate to emotional biases, meaning how we respond to different positive and negative emotions," said Jyoti Mishra, senior author of the study, director of the NEATLabs and assistant professor in the Department of Psychiatry at UCSD School of Medicine.
The study, published in Friday's online edition of Cerebral Cortex, involved 147 participants ages 18 to 85. The subjects performed a simple cognitive task of determining which direction an arrow was pointed while faces with different emotions were presented in the background.
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"We found that when faces emoting anger were presented as distractors, they significantly slowed simple cognitive responses in lonelier individuals," Mishra said. "This meant that lonelier individuals paid more attention to threatening stimuli, such as the angry faces.
"For wisdom, on the other hand, we found a significant positive relationship for response speeds when faces with happy emotions were shown, specifically individuals who displayed wiser traits, such as empathy, had speedier responses in the presence of happy stimuli," she said.
Electroencephalogram-based brain recordings showed that the part of the brain called the temporal-parietal junction was activating differently in lonelier versus wiser individuals. TPJ is important for processing theory of mind, or the degree of capacity for empathy and understanding of others. The study found it more active in the presence of angry emotions for lonelier people and more active in the presence of happy emotions for wiser people.
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Researchers also noted greater activity to threatening stimuli for lonelier individuals in the brain region allocating attention, while wisdom was significantly related to enhanced happy emotion-driven activity in the part of the brain responsible for social characteristics like empathy.
"This study shows that the inverse relationship between loneliness and wisdom that we found in our previous clinical studies is at least partly embedded in neurobiology and is not merely a result of subjective biases," said study author Dr. Dilip V. Jeste, senior associate dean for the Center of Healthy Aging and Distinguished Professor of Psychiatry and Neurosciences at UCSD School of Medicine.
"These findings are relevant to the mental and physical health of individuals because they give us an objective neurobiological handle on how lonelier or wiser people process information," Mishra said. "Having biological markers that we can measure in the brain can help us develop effective treatments.
"Perhaps we can help answer the question, 'Can you make a person wiser or less lonely?' The answer could help mitigate the risk of loneliness," she continued.
