This wonderful book was written by Rick Hanson PhD and Richard Mendius MD. I attended the conference and had the pleasure of hearing Dr. Hanson speak. Some Key Findings: Meditation activates the PNS through multiple pathways. From page 85, chapter Cooling the Fires-
Regular Meditation: Increases gray matter in the insula, hippocampus, prefrontal cortex; reduces cortical thinning due to aging in prefrontal regions strengthened by meditation; improves psychological functions associated with these regions, including attention, compassion, and empathy.
Increases activation of left frontal regions which lifts mood.
Increases power and reach of fast,gamma brain waves in experienced Tibetan practitioners, brainwaves are the weak but measurable electrical waves produced by large numbers of neurons firing rhythmically together
Decreases stress related cortisol.
Strengthens the immune system.
Helps a variety of medical conditions, including cardiovascular disease, asthmas, type 2 diabetes, PMS, and chronic pain.
Helps psychological condiitons, including insomnia, anxiety, phobias, and eating disorders.