Someone started a thread on “The Tao Bums” forum with the title: “Breath Gets Cut Off During Meditation”, and asked for “any advice (on how) to overcome it”.
Yuanwu, the twelfth century Chinese Zen teacher and author of “The Blue Cliff Record”, wrote:
You must strive with all your might to bite through here and cut off conditioned habits of mind. Be like a person who has died the great death: after your breath is cut off, then you come back to life. Only then do you realize that it is as open as empty space. Only then do you reach the point where your feet are walking on the ground of reality.
(Zen Letters, translated by J.C. and Thomas Cleary, pg 84)
Yuanwu made a connection between “biting through here” and the ability to “cut off conditioned habits of mind”, where to “cut off conditioned habits of mind” meant to cease any voluntary activity of thought or direction of the body, just as though one were letting go of life itself. Yuanwu stated that as a matter of course, such a cessation of habitual activity results in a feeling that the activity of breath in the body has been cut off, and causes a person to come to their senses as though returned to life from the dead. Returned to one’s senses, the location of awareness shifts in three-dimensional space without restriction, as in empty space; activity in the body is engendered by virtue of the location of awareness and the nerve impulses generated by ligaments and fascia as they stretch in response to the relaxed necessity of breath, without volition.
A practice that has been very helpful to me in coming to my senses would be:
…the placement of the little fingers against the lower abdomen in the posture of (zazen) provides a direct sense of the geometry of support for the lower spine initiated through reciprocal innervation. In particular, …if the little fingers leave the abdomen, awareness of the forward and backward motion wherever consciousness takes place and relaxation of the activity of the body in awareness can restore the little fingers to the abdomen. Similarly, …if the elbows lose their angle from the body, awareness of the side-to-side motion wherever consciousness takes place and relaxation of the activity of the body in awareness can restore the angle. Likewise, …if the shoulders lose their roundedness, awareness of (the rotation) left and right wherever consciousness takes place and relaxation of the activity of the body in awareness can help restore the round to the shoulders.
That I came up with in 2005, and was the basis for my website “The Mudra of Zen”. I still seem to attend to the location of awareness in space from time to time, as necessary to the movement of breath.