Following up on our series on trance (see the post ‘What Does Trance Feel Like?‘ which contains reference to the series of posts on this subject), one interesting practice that appears to be quite similar is what happens when one does apnea diving (also called freediving), because it requires brain adaptations.
Efficient apnea diving requires careful management of oxygen; the brain being the main oxygen consumer even basic apnea management requires to learn how to deplete the oxygen flow to the brain, and in particular the frontal cortex. This practice will significantly increase the time before breathing becomes absolutely necessary.
At the same time, this brain exercise necessarily leads to an alternate form of consciousness. Therefore, apneists are quickly in a form of trance state, focused on their performance of avoiding the urge to breathe again. Hypoxia then leads also to all sorts of visions and possibly dangerous behaviors.
Hat-tip to Laurent Coulon for the discussion on apnea diving and trance.
