Thanks very much, Jared! I'm going to be starting a PhD into the neurophenomenology of breathwork and meditation this coming October, so I'm excited to personally dive in further to this topic as well!

I would suggest one of Stan's (many) books: 'Holotropic Breathwork: A New Approach to Self-Exploration and Therapy'.

Or, if you just wanted to look at some articles: http://www.holotropic.com/media/articles/