Hochman JI, S.O.T Category I: Dural Dysfunction Today's Chiro, Jan/Feb 1997;26 (1) :30-41

The idea of Category I includes the notion that the first bodily system to react to stress is the central nervous system. This certainly makes sense from the chiropractic viewpoint, but the truth of such a statement may be difficult to prove scientifically. Category I is defined as cranio-sacral dural dysfunction, affecting the occiput, sacrum, dural coverings of the brain and cord, supply and physiology of the cerebrospinal fluid, cranial mechanics and most importantly, the functioning of the central nervous system. Presented in this paper is the anatomy of the Category I Dural System, the Primary Respiratory Mechanism and the Cranial Rhythmic Impulse, Basic One Cranial Procedure, Category One Block Placement, The Dollar and Crest Signs, The SB+ and SB- Cough Test, The Vasomotor Response and Occipital Fiber Analysis.