New insights into the neural activity linked to loneliness could help us improve the way we treat it, researchers say – and reduce the numerous physical and mental health impacts associated with feelings of being lonely.
Our brains react to loneliness in an almost exactly opposite way to the way they react to feelings of wisdom, according to a new study. This adds to a growing body of research that suggests that the wiser we think we are, the less lonely we feel.
While the loneliness-wisdom association has been spotted before, this is the first time scientists have been able to look at the apparent link on the neural level.
"We were interested in how loneliness and wisdom relate to emotional biases, meaning how we respond to different positive and negative emotions," says neuroscientist Jyoti Mishra, from the University of California San Diego (UCSD).
With the help of 147 participants aged 18 to 85 and electroencephalogram (EEG) brain recordings, Mishra and her colleagues focussed their attention on the temporal-parietal junction (TPJ), a brain hub where internal and external information is collected and then processed.
Volunteers were given a self-assessment survey to evaluate their feelings of loneliness and wisdom, and then asked to complete a simple cognitive test while a selection of faces with positive (happy), negative (sad), threatening (angry), or neutral expressions were displayed in the background.
The self-assessed lonelier individuals were most distracted by the angry faces – their TPJ cognitive processes slowed down. The wiser individuals, however, responded more to the happy faces, which sped up their TPJ cognitive processes. The neural reactions were in many ways opposites depending on whether someone was feeling lonely or wise.
The researchers also found that the lonely-angry reaction caused more activity in the brain's left superior parietal cortex (important for allocating attention), while the wise-happy reaction caused more activity in the brain's left insula (which handles social characteristics such as 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," says neuropsychiatrist Dilip Jeste, from UCSD.
While the team says that much more research will be required – including analysing people over a longer period of time – the study does provide a useful indication of how lonelier individuals process information in the brain.
It doesn't appear that age has any bearing on this information processing, but with loneliness now reaching " epidemic" levels in the words of the researchers, any help that medical experts can get in managing these feelings (and their impact on mental and physical health) has to be useful.
The TPJ part of the brain is also being investigated as a way to treat conditions like auditory hallucinations and tinnitus, and it's possible that some kind of neural stimulation could help relieve a strong sense of loneliness too.
"Having biological markers that we can measure in the brain can help us develop effective treatments," says Mishra.
"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."
The research has been published in Cerebral Cortex.