Social isolation decreases myelin

December, 2012

A mouse study demonstrates that prolonged social isolation can lead to a decrease in myelin, an effect implicated in a number of disorders, including age-related cognitive decline.

Problems with myelin — demyelination (seen most dramatically in MS, but also in other forms of neurodegeneration, including normal aging and depression); failure to develop sufficient myelin (in children and adolescents) — are increasingly being implicated in a wide range of disorders. A new animal study adds to that evidence by showing that social isolation brings about both depression and loss of myelin.

In the study, adult mice were isolated for eight weeks (which is of course longer for a mouse than it is to us) to induce a depressive-like state. They were then introduced to a mouse they hadn’t seen before. Although typically very social animals, those who had been socially isolated didn’t show any interest in interacting with the new mouse — a common pattern in human behavior as well.

Analysis of their brains revealed significantly lower levels of gene transcription for oligodendrocyte cells (the components of myelin) in the prefrontal cortex. This appeared to be caused by a lower production of heterochromatin (tightly packed DNA) in the cell nuclei, producing less mature oligodendrocytes.

Interestingly, even short periods of isolation were sufficient to produce changes in chromatin and myelin, although behavior wasn’t affected.

Happily, however, regardless of length of isolation, myelin production went back to normal after a period of social integration.

The findings add to the evidence that environmental factors can have significant effects on brain development and function, and support the idea that socializing is good for the brain.


Related News

A study involving 845 secondary school students has revealed that each hour per day spent watching TV, using the internet or playing computer games at average age 14.5 years was associated with poorer GCSE grades at age 16.

We've seen a number of studies showing the value of music training for children's development of language skills. A new study has investigated what happens if the training doesn't begin until high school.

There's been a lot of talk in recent years about the importance of mindset in learning, with those who have a “growth mindset” (ie believe that intelligence can be developed) being more academically successful than those who believe that intelligence is a fixed attribute.

Two studies indicate that young people carrying the “Alzheimer’s gene” (ApoE4) do not have the pathological changes found later in life. The first study, involving 1412 adolescents, found no differences in hippocampal volume or asymmetry as a function of gene status.

A study involving 187 children and adolescents with multiple sclerosis, plus 44 who experienced their first neurologic episode (clinically isolated syndrome) indicative of MS, has found that 35% of those with MS and 18% of those with clinically isolated syndrome were cognitively impaired.

I’ve talked before about how even mild head injuries can have serious consequences, and in recent years we’ve seen growing awareness of the long-term dangers of sports’ concussions (especially for

I’ve spoken before about the effects of motivation on test performance.

Chronic use of alcohol and marijuana during youth has been associated with poorer neural and cognitive function, which appears to continue into adulthood.

There have been a number of studies in the past few years showing how poverty affects brain development and function.

Adding to the growing evidence for the long-term cognitive benefits of childhood music training, a new study has found that even a few years of music training in childhood has long-lasting benefits for auditory discrimination.


Subscribe to Latest newsSubscribe to Latest news