Thanks for the clear explanation of this fascinating research. Respiratory Therapists and paramedics have been using control of the inhale vs exhale phases of ventilation to influence the progression of brain *injury* for a very long time. We know this works by influencing acid-base balance systemically. As a yogi and priorly a medic, I was able to observe the effects of modulating the 4 phases of breathing on my own CO2 /02 levels sometimes. With a form of forceful, rapid exhale called Kapalabhati (skull-shining breath), I could expel up to 1/3 more CO2 for short periods. The 4 phases of breathing that yoga teaches us to experiment with are inhale-pause-exhale-pause, and these two pauses are observed to have very different effects. The pause after inhale, in a word, is more stimulating and that after exhale is more calming. Yoga teaches us two things that are important to using our breath and our bodies to create emotional, perceptual, and mental shifts: first is that to be greatly effective, practice is necessary. Practice need not be long, but learning and using the breath, postural and focus patterns of yoga in low-stress times (say, 5-15 minutes several times a week or more of intentional practice) makes them radically more effective in times of need. As a teacher of these practices, I've heard too many people dismiss them because they "tried that once, and it didn't work." Secondly, learning the basic patterns and how they *feel* (interoception, mentioned in the last sentence of the abstract) is the basis of learning how to interact with our own body-minds. Thanks for bringing our attention to this research of the mechanisms of how this all works.