University of California Los Angeles researchers have discovered that meditation physically alters the brain, possibly allowing it to process information more quickly.
Long-term meditators have larger amounts of gyrification, or folding of the cortex, than people who do not meditate. Indeed, there was a direct correlation between the amount of gyrification and the number of years spent meditating.
The cerebral cortex is the outermost layer of neural tissue, and plays a key role in memory, attention, thought and consciousness. Gyrification increases the surface area of the brain, and is believed to enhance neural processing.
The researchers took MRI scans of 50 meditators, 28 men and 22 women, and compared them to 50 control subjects matched for age, handedness and sex. The scans for the controls were obtained from an existing MRI database, while the meditators were recruited from various meditation venues.
The meditators had on average 20 years' experience in Samatha, Vipassana, Zen and other techniques.
The team found pronounced differences across a wide area of the cortex, including the left precentral gyrus, the left and right anterior dorsal insula, the right fusiform gyrus and the right cuneus.
Perhaps most interesting, though, was the correlation between the number of meditation years and the amount of insular gyrification.
"The insula has been suggested to function as a hub for autonomic, affective and cognitive integration," says assistant professor Eileen Luders.
"Meditators are known to be masters in introspection and awareness as well as emotional control and self-regulation, so the findings make sense that the longer someone has meditated, the higher the degree of folding in the insula."