10-Week Hatha Yoga Increases Right Hippocampal Density Compared to Active and Passive Control Groups: A Controlled Structural cMRI Study

Materials and Methods: We conducted a longitudinal structural MRI study to investigate changes in gray matter (GM) density following a Yoga intervention. In order to check the repeatability of the results two data acquisition periods (cohorts) with the same study design were done. Yoga naive subjects (n = 19/n = 20) received a Yoga intervention once a week for 75 minutes over a period of 10 weeks. Control groups included active sport subjects (n = 10/n = 22) and passive subjects (n = 17/n = 14). All participants could choose their group assignment by their own preference. A longitudinal and group comparison was done by voxelbased-morphometric analyses before and after the intervention. In addition, blood pressure was taken before and after the study period as a controlling instrument. Finally, the results of the two cohorts were reported into a comprising data set for a general conclusion on Yoga effects.