Prolonged loneliness can transform the brain to make you MORE antisocial

Animals kept in isolation produce less myelin in brain regions crucial for emotional behaviour

Changes in the amount of myelin in the brain have been seen before in psychiatric disorders

However, research shows myelin production returned to normal after a period of social re-integration



Prolonged loneliness can affect transform the brain in a way that makes those who suffer it less able to relate to others, a new study suggests.

Research showed that animals kept in isolation for long periods produce less myelin - white matter - in parts of their brain crucial for complex emotional behaviour.

The findings from the University at Buffalo and Mt Sinai School of Medicine shed new light on the brain's ability to adapt to environmental changes - a phenomenon known as brain plasticity.

Damaging: A new study shows how prolonged loneliness can actually change the structure of animals' brains, making them less able to relate to peers once their period of isolation is over

Changes in the brain's white matter have been seen before in psychiatric disorders, and demyelinating disorders like multiple sclerosis have also had an association with depression.

Recently, myelin changes were also seen in very young animals or adolescents responding to environmental changes.

But Karen Dietz, lead author on the study published online in the journal Nature Neuroscience, said: 'This research reveals for the first time a role for myelin in adult psychiatric disorders.

'It demonstrates that plasticity in the brain is not restricted to neurons, but actively occurs in glial cells, such as the oligodendrocytes, which produce myelin.'

Myelin is a crucial fatty material that wraps the axons of neurons, helping them signal effectively. Normal nerve function is lost in demyelinating disorders, such as MS and the rare, fatal childhood disease, Krabbe's disease.

The paper revealed how the stress of social isolation disrupts the sequence in which the myelin-making cells, the oligodendrocytes, are formed.



Mental health: Changes in the brain's white matter have been seen before in psychiatric disorders, and demyelinating disorders like multiple sclerosis have also had an association with depression

In an experiment, adult mice - normally social animals - were isolated for eight weeks to induce a depressive-like state, before being introduced to a mouse they hadn't met before.

While mice are normally highly motivated to be social, those who had been socially isolated did not show any interest in interacting with the new mouse, a typical model of social avoidance and withdrawal.

ARE WE GETTING MORE STUPID? Our intelligence and behaviour requires optimal functioning of a large number of genes, which requires enormous evolutionary pressures to maintain.

Now, in a provocative theory, a team from Stanford University claim we are losing our intellectual and emotional capabilities because the intricate web of genes which endows us with our brain power is particularly vulnerable to mutations - and these mutations are not being selected against our modern society because we no longer need intelligence to survive.

But we shouldn't lose any sleep over our diminishing brain power - as by the time it becomes a real problem technology will have found a solution making natural selection obsolete, the researchers say in a paper published today in Cell Press journal Trends in Genetics.

Brain tissue analysis of the isolated animals revealed significantly lower than normal levels of gene transcription for oligodendrocyte cells in the prefrontal cortex, a brain region responsible for emotional and cognitive behavior.

'This research provides the first explanation of the mechanism behind how this brain plasticity occurs showing how this change in the level of social interaction of the adult animal resulted in changes in oligodendrocytes,' said Dr Dietz, a research scientist in the Department of Pharmacology and Toxicology in the UB School of Medicine and Biomedical Sciences.

The key change was that cellular nuclei in the prefrontal cortex contained less heterochromatin, a tightly packed form of DNA material, which is unavailable for gene expression.

'This process of DNA compaction is what signifies that the oligodendrocytes have matured, allowing them to produce normal amounts of myelin,' Dr Dietz said. 'We have observed in socially isolated animals that there isn't as much compaction, and the oligodendrocytes look more immature.

'As adults age, normally, you would see more compaction, but when social isolation interferes, there's less compaction and therefore, less myelin being made.'

She added, however, that the research also showed that myelin production went back to normal after a period of social integration, suggesting that environmental intervention was sufficient to reverse the negative consequences of adult social isolation.

Dr Dietz said the findings have implications for future questions regarding MS and other myelin disorders.