Arab Press

بالشعب و للشعب
Saturday, Aug 30, 2025

Social isolation linked to changes in brain structure and lower cognition ability

Social isolation linked to changes in brain structure and lower cognition ability

Why do we get a buzz from being in large groups at festivals, jubilees and other public events? According to the social brain hypothesis, it’s because the human brain specifically evolved to support social interactions. Studies have shown that belonging to a group can lead to improved wellbeing and increased satisfaction with life.

Unfortunately though, many people are lonely or socially isolated. And if the human brain really did evolve for social interaction, we should expect this to affect it significantly. Our recent study, published in Neurology, shows that social isolation is linked to changes in brain structure and cognition – the mental process of acquiring knowledge – it even carries an increased risk of dementia in older adults.

There’s already a lot of evidence in support of the social brain hypothesis. One study mapped the brain regions associated with social interaction in approximately 7,000 people. It showed that brain regions consistently involved in diverse social interactions are strongly linked to networks that support cognition, including the default mode network (which is active when we are not focusing on the outside world), the salience network (which helps us select what we pay attention to), the subcortical network (involved in memory, emotion and motivation) and the central executive network (which enables us to regulate our emotions).

We wanted to look more closely at how social isolation affects grey matter – brain regions in the outer layer of the brain, consisting of neurons. We, therefore, investigated data from nearly 500,000 people from the UK Biobank, with a mean age of 57. People were classified as socially isolated if they were living alone, had social contact less than monthly and participated in social activities less than weekly.

Our study also included neuroimaging (MRI) data from approximately 32,000 people. This showed that socially isolated people had poorer cognition, including in memory and reaction time, and lower volume of grey matter in many parts of the brain. These areas included the temporal region (which processes sounds and helps encode memory), the frontal lobe (which is involved in attention, planning and complex cognitive tasks) and the hippocampus – a key area involved in learning and memory, which is typically disrupted early in Alzheimer’s disease.

We also found a link between the lower grey matter volumes and specific genetic processes that are involved in Alzheimer’s disease.

There were follow-ups with participants 12 years later. This showed that those who were socially isolated, but not lonely, had a 26% increased risk of dementia.


Underlying processes


Social isolation needs to be examined in more detail in future studies to determine the exact mechanisms behind its profound effects on our brains. But it is clear that, if you are isolated, you may be suffering from chronic stress. This in turn has a major impact on your brain, and also on your physical health.

Another factor may be that if we don’t use certain brain areas, we lose some of their function. A study with taxi drivers showed that the more they memorised routes and addresses, the more the volume of the hippocampus increased. It is possible that if we don’t regularly engage in social discussion, for example, our use of language and other cognitive processes, such as attention and memory, will diminish.

This may affect our ability to do many complex cognitive tasks – memory and attention are crucial to complex cognitive thinking in general.


Tackling loneliness


We know that a strong set of thinking abilities throughout life, called “cognitive reserve”, can be built up through keeping your brain active. A good way to do this is by learning new things, such as another language or a musical instrument. Cognitive reserve has been shown to ameliorate the course and severity of ageing. For example, it can protect against a number of illnesses or mental health disorders, including forms of dementia, schizophrenia and depression, especially following traumatic brain injury.

There are also lifestyle elements that can improve your cognition and wellbeing, which include a healthy diet and exercise. For Alzheimer’s disease, there are a few pharmacological treatments, but the efficacy of these need to be improved and side effects need to be reduced. There is hope that in the future there will be better treatments for ageing and dementia. One avenue of inquiry in this regard is exogenous ketones – an alternative energy source to glucose – which can be ingested via nutritional supplements.

But as our study shows, tackling social isolation could also help, particularly in old age. Health authorities should do more to check on who is isolated and arrange social activities to help them.

When people are not in a position to interact in person, technology may provide a substitute. However, this may be more applicable to younger generations who are familiar with using technology to communicate. But with training, it may also be effective in reducing social isolation in older adults.

Social interaction is hugely important. One study found that the size of our social group is actually associated with the volume of the orbitofrontal cortex (involved in social cognition and emotion).

But how many friends do we need? Researchers often refer to “Dunbar’s number” to describe the size of social groups, finding that we are not able to maintain more than 150 relationships and only typically manage five close relationships. However, there are some reports which suggest a lack of empirical evidence surrounding Dunbar’s number and further research into the optimal size of social groups is required.

It is hard to argue with the fact that humans are social animals and gain enjoyment from connecting with others, whatever age we are. But, as we are increasingly uncovering, it also crucial for the health of our cognition.

Newsletter

Related Articles

Arab Press
0:00
0:00
Close
After the Shock of Defeat, Iranians Yearn for Change
YouTube Altered Content by Artificial Intelligence – Without Permission
Iran Faces Escalating Water Crisis as Protests Spread
More Than Half a Million Evacuated as Typhoon Kajiki Heads for Vietnam
HSBC Switzerland Ends Relationships with Over 1,000 Clients from Saudi Arabia, Lebanon, Qatar, and Egypt
Sharia Law Made Legally Binding in Austria Despite Warnings Over 'Incompatible' Values
Dogfights in the Skies: Airbus on Track to Overtake Boeing and Claim Aviation Supremacy
Tim Cook Promises an AI Revolution at Apple: "One of the Most Significant Technologies of Our Generation"
Are AI Data Centres the Infrastructure of the Future or the Next Crisis?
Miles Worth Billions: How Airlines Generate Huge Profits
Zelenskyy Returns to White House Flanked by European Allies as Trump Pressures Land-Swap Deal with Putin
Beijing is moving into gold and other assets, diversifying away from the dollar
Trump Backs Putin’s Land-for-Peace Proposal Amid Kyiv’s Rejection
Zelenskyy to Visit Washington after Trump–Putin Summit Yields No Agreement
Iranian Protection Offers Chinese Vehicle Shipments a Cost Advantage over Japanese and Korean Makers
United States Sells Luxury Yacht Amadea, Valued at Approximately $325 Million, in First Sale of a Seized Russian Yacht Since the Invasion of Ukraine
Saudi Arabia accelerates renewables to curb domestic oil use
Cristiano Ronaldo and Georgina Rodríguez announce engagement
Asia-Pacific dominates world’s busiest flight routes, with South Korea’s Jeju–Seoul corridor leading global rankings
Private Welsh island with 19th-century fort listed for sale at over £3 million
Sam Altman challenges Elon Musk with plans for Neuralink rival
Australia to Recognize the State of Palestine at UN Assembly
The Collapse of the Programmer Dream: AI Experts Now the Real High-Earners
Armenia and Azerbaijan to Sign US-Brokered Framework Agreement for Nakhchivan Corridor
British Labour Government Utilizes Counter-Terrorism Tools for Social Media Monitoring Against Legitimate Critics
WhatsApp Deletes 6.8 Million Scam Accounts Amid Rising Global Fraud
Texas Residents Face Water Restrictions While AI Data Centers Consume Millions of Gallons
India Rejects U.S. Tariff Threat, Defends Russian Oil Purchases
United States Establishes Strategic Bitcoin Reserve and Digital Asset Stockpile
Thousands of Private ChatGPT Conversations Accidentally Indexed by Google
China Tightens Mineral Controls, Curtailing Critical Inputs for Western Defence Contractors
JPMorgan and Coinbase Unveil Partnership to Let Chase Cardholders Buy Crypto Directly
British Tourist Dies Following Hair Transplant in Turkey, Police Investigate
WhatsApp Users Targeted in New Scam Involving Account Takeovers
Trump Deploys Nuclear Submarines After Threats from Former Russian President Medvedev
Germany’s Economic Breakdown and the Return of Militarization: From Industrial Collapse to a New Offensive Strategy
Germany Enters Fiscal Crisis as Cabinet Approves €174 Billion in New Debt
IMF Upgrades Global Growth Forecast as Weaker Dollar Supports Outlook
Politics is a good business: Barack Obama’s Reported Net Worth Growth, 1990–2025
UN's Top Court Declares Environmental Protection a Legal Obligation Under International Law
"Crazy Thing": OpenAI's Sam Altman Warns Of AI Voice Fraud Crisis In Banking
Japanese Prime Minister Vows to Stay After Coalition Loses Upper House Majority
President Trump Diagnosed with Chronic Venous Insufficiency After Leg Swelling
Man Dies After Being Pulled Into MRI Machine Due to Metal Chain in New York Clinic
FIFA Pressured to Rethink World Cup Calendar Due to Climate Change
Iranian President Reportedly Injured During Israeli Strike on Secret Facility
Kurdistan Workers Party Takes Symbolic Step Towards Peace in Northern Iraq
BRICS Expands Membership with Indonesia and Ten New Partner Countries
Elon Musk Founds a Party Following a Poll on X: "You Wanted It – You Got It!"
AI Raises Alarms Over Long-Term Job Security
×