(CNN)As many people face the prospect of being alone for the holidays, new science is showing how loneliness might actually help build structures in the brain tied to imagination.
Lonely people were more likely to have increased activity in areas of the brain tied to reminiscing, thinking about others and future planning, according to a study published Tuesday in the journal Nature Communications.
The researchers had hypothesized that the so-called default network in the brain, which is involved in memory and social cognition, was likely to undergo changes related to loneliness.
"What surprised us was that overwhelmingly was the largest effect in the data," said lead study author Nathan Spreng, associate professor of neurology at McGill University in Montreal.
Ties between these areas had become strengthened and gray matter volume there was greater than in those who weren't lonely.
The results converged on the default network as most impacted by perceived isolation and loneliness.
A wealth of data
Well before the pandemic, loneliness was increasingly being seen as a public health concern, enough so that the United Kingdom appointed a minister for loneliness in 2018.
Data has shown that lonely adults are about 1.64 times more likely to develop dementia compared with those who don't self-report loneliness, according to a 2015 review of worldwide studies.
Results like those motivated the researchers to comb through brain images from 40,000 subjects, all pulled from the UK Biobank, a large-scale database storing biomedical information from some 500,000 British people.
Participants in that study, who ranged in age from 40 to 69, filled out assessments that included questions asking whether they felt lonely or not.
The researchers then compared MRI scans of self-identified lonely people with those who did not feel loneliness on a regular basis.
The sheer size of the data sample is a rarity in this area of science, Spreng said, and it was the result of the biobank dramatically scaling up its available brain images this past February.
"We started working with that immediately when they came out and it was very exciting," Spreng said.
Prior to this, most of his neuroscience work had focused on cohorts with just hundreds of participants -- a significant number in itself. But now, with tens of thousands of subjects' data to draw from, there was a lot more to learn.