Loneliness, brain shrinkage, and memory decline: What you need to know

Isolated and alone? Your brain could be paying the price, research shows


Loneliness, the feeling of being socially isolated, has been linked to changes in our brains, according to a recent research study. As people experience more social isolation, their memory tends to decline over time, and this link appears to be a one-way street – loneliness affecting memory, rather than the other way around.

This might sound a bit scientific, but essentially, loneliness seems to impact parts of our brains that regulate our motivation and how we respond to stress. These areas are called the ventral striatum and the limbic system. So, when you're feeling lonely, it can mess with these brain regions, which isn't great for your mental health.

But it's not just about feeling a bit down. Loneliness and social isolation have been connected to some serious health problems like heart disease, depression, and cognitive decline (that's when your thinking and memory get worse). If you're not in the best health, you might also find yourself feeling more isolated or lonely.

Now, here's the really interesting part: a recent study focused on older folks found that those who didn't have much social interaction had smaller brains, especially in areas that are often affected by dementia (a condition that causes memory problems). But hold on, this study didn't prove that loneliness directly causes your brain to shrink – it just showed a connection between the two.

Individuals in the older age bracket with limited social interaction may be at a higher risk of experiencing a reduction in overall brain volume, particularly in regions that are often impacted by dementia, compared to their counterparts who engage in regular social interactions, according to a study recently published in Neurology, the medical journal of the American Academy of Neurology.

The study involved nearly 9,000 people, all around 73 years old, and none of them had dementia. They had brain scans and health check-ups. To figure out how often they talked to friends or family who didn't live with them, they were asked a simple question: "How often are you in contact with relatives or friends who do not live with you?" The options ranged from every day to seldom.

Guess what they found? The folks with the least social contact had smaller brains compared to those who chatted with others more often. The total brain volume, which includes both white and grey matter, was slightly lower in the lonely group. And they also had smaller volumes in areas of the brain related to memory.

The researchers considered other things that could affect brain size, like age, diabetes, smoking, and exercise. Plus, the lonely group had more little brain problems called white matter lesions.

“Social isolation is a growing problem for older adults,” said study author Toshiharu Ninomiya,  of Kyushu University in Fukuoka, Japan. “These results suggest that providing support for people to help them start and maintain their connections to others may be beneficial for preventing brain atrophy and the development of dementia.”

Now, here's the thing about depression. It seems that feeling lonely can make you more likely to feel down, and this partly explains why lonely folks had smaller brains. But depression didn't account for everything, only about 15% to 29% of the connection.

So, what does all of this mean? Well, while this study can't say for sure that loneliness directly causes your brain to shrink, it does suggest that social isolation might not be great for your noggin. Some other studies have shown that getting older folks involved in social groups can actually improve their brain health and memory.

This study focused on older Japanese people, so the findings might not apply to everyone, especially younger folks or people from different backgrounds. But the takeaway here is pretty clear – staying socially connected might just be good for your brain.

“While this study is a snapshot in time and does not determine that social isolation causes brain atrophy, some studies have shown that exposing older people to socially stimulating groups stopped or even reversed declines in brain volume and improved thinking and memory skills, so it’s possible that interventions to improve people’s social isolation could prevent brain volume loss and the dementia that often follows,” Ninomiya said.