mhodges

this paper describes and analyzes ways that enable a human to consciously and purposefully manage the frequency of heart contractions "The sequence of the processes developing in the human central nervous system in the implementation of cardio-respiratory synchronization, may be represented by the following stages: (i) the perception of light or sound signal, which speci¯es the frequency of breathing and process evaluation of the signal; (ii) the formation of task to control the rate of breathing; (iii) reproduction of breathing rate in strict accordance with the frequency of the driving signal; (iv) the interaction of respiratory and cardiac centers in the brain; (v) synchronization of respiratory rhythms and cardiac centers; (vi) transmission of efferent signals to the heart from the brain via the vagus nerves; (vii) the interaction of signals arriving via the vagus nerves with rhythmogenical structures of the heart; (viii) heart reproduces rate signals -- the development of cardio-respiratory synchronization." "...3.2. Heart rhythm management by means of arbitrary abdomen muscle tension. The analysis of the falling heartbeat rate by means of arbitrary muscle tension was observed from a person who claimed to have the ability to arbitrary stop heart activity. During laboratory testing, the testee stopped his heart for 7 s; this was objectively registered on the electrocardiogram" On the conscious control of the human heart Vladimir M. Pokrovskii and Lily V. Polischuk, J. Integr. Neurosci. 11, 213 (2012). DOI: 10.1142/S0219635212500161

You can hold your breath until you black out without any threat of death. If you're hypoxic for over 4 minutes you are at risk of permanent brain injury, but simply losing consciousness doesn't imply brain damage. Black outs happens to freedivers during competitions all the time, as it happened to me while attempting to swim 90 meters underwater a couple weeks ago. In the case of a black out underwater of course there is risk of drowning which is why we never do these kinds of things without a trained rescue partner. Here's a video you may enjoy It shows yoga teacher Simon Borg-Olivier slowing his heart beat from 88 to 32 beats per minute in 45 seconds. Why is this important to understand? I don't believe its even been proven to be true. source http://depthinc.tumblr.com/post/45976648236/a-test-of-proof