Craniosacral therapy (also called cranial osteopathy or cranial therapy) is a method of alternative medicine used by craniosacral therapists or osteopaths to assess and enhance the functioning of the patient by accessing their primary respiratory mechanism, which consists of the membranes and cerebrospinal fluid of the central nervous system. Proponents claim that measurements of craniosacral motion are a function of the cardiovascular system, and that by working with the body, including the skull they can remove restrictions in the flow of cerebrospinal fluid, relieving stress, decreasing pain, and enhancing overall health. Opponents claim that the therapy has been shown to be without scientific basis, and some studies that support the therapy have been criticized for poor methodology.