Even before the mandate of social distancing, loneliness in the midst or far from the madding crowd has been undermining our mental and physical health. The loss of meaningful interpersonal connections has become so common that “loneliness epidemic” is common parlance. “Loneliness puts us at a greater risk of coronary heart disease, dementia and depression,” says Vivek H Murthy, the 19th surgeon general of the United States and Biden’s nominee to be the 21st, in his book Together: Loneliness, Health and What Happens When We Find Connection.
Research over the last decade has shown that loneliness is associated with compromised immunity, increased suicide risk and mortality, and poses a major public health concern. Countering the negativity of loneliness, studies show, is the positive and protective personality trait of wisdom, defined as the ability to think and act using knowledge, experience, insight, and empathy toward others.
The neurobiological basis for this inverse relationship between loneliness and wisdom is the focus of a new study published in Cerebral Cortex, “Cognitive and Neural Correlates of Loneliness and Wisdom during Emotional Bias.”
In this article researchers at the University of California San Diego School of Medicine report specific regions of the brain respond to emotional stimuli related to loneliness and wisdom in opposing ways.
“We were interested in how loneliness and wisdom relate to emotional biases, meaning how we respond to different positive and negative emotions,” says Jyoti Mishra, PhD, senior author of the study, director of the Neural Engineering and Translation Labs (NEATLabs) and assistant professor in the Department of Psychiatry at UC San Diego School of Medicine.
The study involved 147 healthy participants, ages 18 to 85. The participants were asked to perform a simple cognitive task of determining which direction an arrow was pointed while faces with different emotions were presented in the background to present an emotional bias.
“We found that when faces emoting anger were presented as distractors, they significantly slowed simple cognitive responses in lonelier individuals. This meant that lonelier individuals paid more attention to threatening stimuli, such as the angry faces,” says Mishra. “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.”
In humans, brain activity within a frequency range of 4 and 7 Hz is referred to as theta activity. Theta rhythms in EEG (electroencephalography) are often detected on the sides of the head when you’re in a relaxed waking state or asleep, whereas beta waves in the 12–38 Hz range dominate when you’re awake, alert, and engaged.
The authors report, loneliness is associated with enhanced angry stimulus-driven theta activity in the region of the brain called temporoparietal junction (TPJ), while wisdom is related to increased TPJ theta activity during happy stimulus processing. TPJ is important for processing 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.
Moreover, lonelier individuals show increased attentiveness to threatening stimuli detectable as greater beta activity in left superior parietal cortex, the brain region important for allocating attention, while wiser individuals show increased happy stimulus-evoked alpha activity in the left insula, responsible for social characteristics like empathy.
These findings demonstrate loneliness and wisdom modulate cognitive neural processing in the context of emotional bias.
“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,” says Dilip V. Jeste, MD, senior associate dean for the Center of Healthy Aging and Distinguished Professor of Psychiatry and Neurosciences at UC San Diego School of Medicine, and a senior author on the study.
“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,” says Mishra. “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.”
Longitudinal and interventional studies investigating these directions are the next steps for the team.
“Ultimately, we think these evidence-based cognitive brain markers are the key to developing better health care for the future that may address the loneliness epidemic,” says Mishra.