Neural correlates of a mystical experience in Carmelite nuns

The recent scientific study done by researchers at University of Montreal on brains of Carmelite Nuns had the goal of identifying the neural correlates of a mystical experience. The brain activity of Carmelite nuns was measured while they were subjectively in a state of union with God.  

"The main limitation of this study was the fact that the subjects were asked to remember and relive a mystical experience rather than actually try to achieve one. Such a strategy was used because the subjects told us a priori that they were not capable of reaching a mystical state at will. In our view, this does not represent a major problem since the phenomenological data indicate that the subjects actually experienced genuine mystical experiences during the Mystical condition. These mystical experiences felt subjectively different than those used to self-induce a mystical state."

You can read the paper here.

There is another recent study using the Spiritual Exercises of St. Ignatius of Loyola: