By Traci Pedersen Associate News Editor Reviewed by John M. Grohol, Psy.D. on January 19, 2014

Engaging in regular meditation or another spiritual practice is linked to a thickening of the brain cortex, according to new research published in JAMA Psychiatry.

This discovery could lead to new insights as to why these activities help guard against depression, particularly in those who are genetically predisposed to the mental health disorder.

Major depression is characterized by a depressed mood for most of the day and a loss of interest in normal activities and relationships. The disease affects about 6.7% of the U.S. population over age 18, according to the National Institute of Mental Health.

This is the first published study investigating whether there is any physical evidence in the brain linked to the protective effects of spirituality and religion against depression.

Theresearch involved 103 adults at either high or low risk of depression, based on family history. Magnetic resonance imaging findings revealed thicker cortices in those participants who placed a high importance on religion or spirituality than those who did not.

Furthermore, the relatively thicker cortex was found in exactly the same regions of the brain that had otherwise shown thinning in people at high risk for depression.

The new study links this extremely large protective benefit of spirituality or religion to previous studies which identified large expanses of cortical thinning in specific regions of the brain in adult offspring of families at high risk for major depression, said Dr. Lisa Miller, professor and director ofClinical Psychologyand director of theSpirituality Mind Body InstituteatTeachers College, Columbia University.

Prior research conducted by Miller and her team revealed a 90 percent decrease in major depression in adults who placed spirituality or religiosity at high importance and whose parents suffered from depression.

The findings showed that although regular attendance at church was not necessary, a strong personal importance placed on spirituality or religion was most protective against major depression in people who were at high familial risk.

More:

How Spirituality Protects the Brain Against Depression