Researchers at Karolinska Institutet in Sweden have found that the human brain has more plasticity than originally thought, thanks to a type of support cell called the oligodendrocyte, which is critical to cell-to-cell communication in the nervous system.

While earlier theories of brain plasticity have been based on lab animals, a study published in the journal Cell indicated that oligodendrocytes are more sophisticated in humans than in rats and mice. This contributes to the human brain’s greater plasticity and adaptability to new situations. A brain’s plasticity refers to the brain’s development being shaped by the demands that are imposed on it.

Oligodendrocytes produce myelin, a substance that speeds nerve impulses and improves function. Previous studies showed that when the nerve cells of laboratory animals needed more myelin, the oligodendrocytes were replaced. So researchers assumed that the same also applied in humans. But in humans, while oligodendrocyte generation is very low, myelin production can be modulated and increased if necessary.

In the Karolinska study, researchers examined the brains of 55 deceased people from under 1 year old to 92 years old. They were able to establish that at birth most oligodendrocytes are immature. They subsequently mature at a rapid rate until the age of 5, when most reach maturity.