Brain images reveal how living alone in social isolation can change the human brain

Humans are said to be social animals, and it is known that living alone with little relationship with humans causes

various physical and mental disadvantages . A new paper published by international research teams in the United Kingdom and China showed that 'social isolation changes the structure of the brain, reduces cognitive ability, and increases the risk of dementia.'

Associations of Social Isolation and Loneliness With Later Dementia --PubMed

Socially isolated people have differently wired brains and poorer cognition – new research

In recent years, a lot of evidence has been reported to support the ' Machiavellian intelligence hypothesis (social brain hypothesis) ' that human intellectual ability has evolved as an adaptation to a complex social environment. In a study mapping brain regions of about 7,000 social interactions, the brain regions that are consistently involved in social interactions are in the brain that support cognition, such as the default mode network and the prominence network . It has been shown to be deeply connected to the network of.

So the research team extracted from UK Biobank , a large UK biobank, to investigate how social isolation affects the risk of dementia and the gray matter of nerve cells (neurons). We analyzed data from 460,000 people. The average age of the people surveyed was 57, and the data included various demographic information, health status, lifestyle, and degree of social isolation.

As a result of the analysis, 'socially isolated people' who live alone and have less social contact and participation in social activities are compared with people who are not socially isolated in a follow-up survey about 12 years later. The risk of dementia was found to be as high as 26%.

In addition, analysis of MRI images of the brain collected from about 32,000 people revealed that socially isolated people have low cognitive abilities such as memory and response, and that the volume of gray matter is small in many areas of the brain. I did. Areas with low gray color included areas deeply related to cognitive ability, such as the temporal lobe involved in sound processing and memory, the frontal lobe involved in attention and complex cognitive tasks, and the hippocampus involved in learning and memory. The research team says. In addition, it was confirmed that less gray matter was associated with specific gene expression for Alzheimer's disease.

The researchers point out that more detailed research is needed on the mechanism by which social isolation affects the brain. On the other hand, at least social isolation can cause chronic stress, 'this in turn has a major impact on your brain and, in turn, on your physical health.'

Also, by not using a specific brain region, there is a possibility that the function controlled by that region will be lost. For example,

studies of taxi drivers have shown that the more routes and addresses you remember, the more hippocampus you have, but on the contrary, by not participating in social interactions, you can use language and memory. It seems that the cognitive process such as can be weakened. 'In general, complex cognitive thinking requires memory and attention, and these declines can affect the ability to perform many complex cognitive tasks,' the research team claims. ..

The research team said, 'Human beings are social animals, and no matter how old they are, they enjoy connecting with others, but as our research is revealing, Social ties are also crucial to cognitive health. '' Health authorities should check for socially isolated people and make more efforts to arrange social activities to help them. ' Said.

in Science, Posted by log1h_ik