Neuroscientists have discovered that an 8-week meditation training program can leave a lasting impression on the human brain.

Researchers from the Massachusetts General Hospital, Boston University, and several other research centers found that the meditation training produced enduring changes in how the brain processed emotional information. The results of their study were published this month in Frontiers in Human Neuroscience.

"The two different types of meditation training our study participants completed yielded some differences in the response of the amygdala -- a part of the brain known for decades to be important for emotion -- to images with emotional content," Gaelle Desbordes, a corresponding author of the report, explained. "This is the first time that meditation training has been shown to affect emotional processing in the brain outside of a meditative state."

In the study, healthy adults with no experience meditating were enrolled in either mindful attention training, cognitively-based compassion training or a health discussion group. Mindful attention meditation cultivates awareness of one's breathing and one's own state of mind, while compassion meditation focuses on cultivating higher levels of empathy. The health discussion group was used as a control. The training occurred for 2 hours each week, or 16 hours total.

When the participants who practiced mindful attention meditation were shown images of people in either emotionally positive, negative, or neutral situations they tended to have less activation in the right amygdala compared to before practicing meditation, suggesting the training improved their emotional stability and response to stress.

The researchers found similar results for those who practiced compassion meditation. However, those who practiced compassion mediation had greater amygdala activity in response to images of suffering, suggesting the training did in fact increase their level of empathy.

No significant changes were seen in those enrolled in the health discussion group.

"We think these two forms of meditation cultivate different aspects of mind," Desbordes explained. "Since compassion meditation is designed to enhance compassionate feelings, it makes sense that it could increase amygdala response to seeing people suffer. Increased amygdala activation was also correlated with decreased depression scores in the compassion meditation group, which suggests that having more compassion towards others may also be beneficial for oneself. Overall, these results are consistent with the overarching hypothesis that meditation may result in enduring, beneficial changes in brain function, especially in the area of emotional processing."

Meditation has played an important role in many religious traditions, including Christianity, Judaism, Hinduism, Sikhism and Islam. The types of meditation used in the study were based on traditional Buddhist practices.

[Meditating in lotus position via Shutterstock]