Two U.S. scientists have updated findings that link a form of Chinese meditation to positive changes in brain structure, suggesting that just 11 hours of practising the technique over a month could help prevent mental illness.

In a paper to be released this week in the online version of the Proceedings of the National Academy of Sciences, researchers Yi-Yuan Tang and Michael Posner report that the practice known as integrative body-mind training (IBMT) can have a positive physical affect on the brain, boosting connectivity and efficiency.

Increases in the integrity of white matter "pathways," which connect the regions of the brain, were shown after MRI scans of 68 students at China's Dalian University of Technology two years ago. The students meditated for about half an hour a day over the course of a month.

Posner said the latest study revisited the 2010 research, when both researchers were working at the University of Oregon, and confirmed what the authors called a "pattern of neural plasticity" induced by the meditation, which focuses on body relaxation, breathing, posture and mental imagery.

"What's happened is we've made further developments to what we found in 2010," Posner said. "We found that after a month of training, there was a change in the white matter around the anterior cingulate cortex, which is part of the self-regulation system. That was the important message."

Improved mood changes

The anterior cingulated is a brain region that helps to regulate emotions and behaviour. The subjects in the experiment reported improved mood changes and also showed lower levels of anxiety, depression, anger and fatigue than students in the control group.

Posner said the confirmation of changes to locations of the brain he described as self-regulatory areas suggests IBMT could help patients suffering from mental disorders, perhaps with as little as 11 hours a month of meditation.

"Many mental illnesses kind of show a lack of self-regulation, for example addictions; for example schizophrenia and borderline personality [disorder]," he explained. "If those disorders show a lack of self-regulation and you can do something to strengthen self-regulation, then perhaps you can prevent or ameliorate these types of mental problems associated with self-regulation."

Tang and Posner said that while other brain-training exercises such as working-memory training or computer-based training were shown to increase myelin — the protective sheath around the brain cells' conducting fibres, or axons — the IBMT group showed improvements in myelination and axon density.