Science, Medicine, and the Cranial Rhythm
James M. Norton, Ph.D.

"Osteopathy is that science which consists of such exact, exhaustive and verifiable knowledge
of the structure and function of the human mechanism,
anatomical physiological and psychological,
including the chemistry and physics of it's [sic] known elements . . . "
(A.T. Still, Autobiography, 1st Edition, 1897)

"What can be asserted without evidence can also be dismissed without evidence."

(Christopher Hitchens, 2003 [])

Summary and Conclusions


Food for Thought 
publications by Norton and/or Hartman
other relevant publications


Craniosacral Therapy at
Aetna Consumer Health Information on Craniosacral Therapy
"Healthy Me" Information on Cranial Therapy from Blue Cross Blue Shield of Massachusetts
The Skeptic's Dictionary - Craniosacral Therapy
Quackwatch - Craniosacral Therapy


Based upon the results of my research, published in original articles accessible through the link provided above, I have come to the following conclusions with respect to the cranial rhythm:


"There is no alternative medicine. There is only scientifically proven, evidence-based medicine supported by solid data or unproven medicine, for which scientific evidence is lacking. Whether a therapeutic practice is 'Eastern' or 'Western,' is unconventional or mainstream, or involves mind-body techniques or molecular genetics is largely irrelevant except for historical purposes and cultural interest." -- Fontanarosa PB, Lundberg GD.  Alternative medicine meets science. Journal of the American Medical Association 280: 1618-1619, 1998.
"There cannot be two kinds of medicine -- conventional and alternative. There is only medicine that has been adequately tested and medicine that has not, medicine that works and medicine that may or may not work. Once a treatment has been tested rigorously, it no longer matters whether it was considered alternative at the outset. If it is found to be reasonably safe and effective, it will be accepted. But assertions, speculation, and testimonials do not substitute for evidence." -- Angell M, Kassirer J.  Alternative Medicine -- The risks of untested and unregulated remedies. New England Journal of Medicine 339:839-841, 1998.


Hartman, S.E., and J.M. Norton.  A Review of King HH and Lay EM,  "Osteopathy in the Cranial Field" in Foundations for Osteopathic Medicine, 2nd edition.  Scientific Review of Alternative Medicine, 8(2):24-28, 2005.   full text

Hartman, S.E., and J.M. Norton.  Craniosacral Therapy Is Not Medicine.  Physical Therapy 82(11):1146-1147, 2002.  full text

Hartman, S.E., and J.M. Norton. Interexaminer Reliability and Cranial Osteopathy.  Scientific Review of Alternative Medicine, 6(1):23-34, 2002.  abstract or full text

Norton, J.M. A Challenge to the Concept of Craniosacral Interaction. AAO Journal 6(4):15- 21, 1996. abstract or full text

Norton, J.M., G. Sibley, and R.E. Broder-Oldach. Characterization of the Cranial Rhythmic Impulse in Healthy Human Adults.  AAO Journal 2(3):9-12, 1992.  summary or full text

Norton, J.M. A Tissue Pressure Model for the Cranial Rhythmic Impulse. JAOA 91(10):975-994, 1991. abstract or full text

skull 1958

"Interexaminer Reliability and Cranial Osteopathy" by Hartman and Norton  (Click on the title for a printer-friendly (PDF) copy of this article recently published in The Scientific Review of Alternative Medicine, Vol. 6, No. 1, Winter 2002, pp. 23-34.)

Abstract:  We assess the mechanism purported to underlie the health treatment regime labeled "cranial osteopathy" or "craniosacral therapy".  We then summarize all published reports on interexaminer reliability associated with this modality, reanalyze some previously published data, and critique Upledger's often-cited study.  Our own and previously published findings suggest that the proposed mechanism for cranial osteopathy is invalid and that interexaminer (and, therefore, diagnostic) reliability is approximately zero.  Since no properly randomized, blinded, and placebo-controlled outcome studies have been published, we conclude that cranial osteopathy should be removed from curricula of colleges of osteopathic medicine and from osteopathic licensing examinations.

A Tissue Pressure Model for the Cranial Rhythmic Impulse (Click on the title for an HTML version of a manuscript that became a JAOA cover article [JAOA 91(10):975-994, 1991; see cover image below] describing a possible physiological basis for the CRI, based on well-established principles of cardiovascular, respiratory, and capillary exchange physiology.)

Abstract:  A tissue pressure model was developed to provide a possible physiological basis for the manifestation of the Cranial Rhythmic Impulse, or CRI. The model assumes that the sensation described as the CRI is related to the activation of slowly adapting cutaneous mechanoreceptors, that the deforming forces stimulating these mechanoreceptors are the tissue pressures of both the examiner and the subject, and that the sources of changes in these tissue pressures are the combined respiratory and cardiovascular rhythms of both examiner and subject. This tissue pressure model utilizes well-documented relationships among vascular pressures, tissue pressures, and cardiovascular and respiratory rhythms. The model generates rhythmic impulses with frequencies and patterns similar to those reported for the CRI, and a significant correlation was found between frequencies calculated from the model and published values for CRI obtained using palpation. These comparisons suggest that the CRI may arise in soft tissues and represents a complex interaction of at least four different physiological rhythms.


haracterization of the Cranial Rhythmic Impulse in Healthy Human Adults  (Click on the title for an HTML version of a manuscript eventually published in the Journal of the American Academy of Osteopathy [AAO Journal 2(3):9-12, 1992].  This is an "in progress" report of initial findings regarding the documentation of the CRI and some of its characteristics in healthy human adults, using the tissue pressure model as a starting point.)
Summary:  The experiments described in this report were designed to provide the kind of quantitative information on the characteristics of the CRI that is not available in the literature and that is essential for the validation of any conceptual model for the origin of the cranial rhythmic impulse. The authors would appreciate feedback concerning the data itself or the methods by which the data were generated. The ultimate goal of research in this area should be to gather and evaluate information on the CRI in a manner that is both scientifically rigorous and clinically relevant to practitioners in the field.

Challenge to the Concept of Craniosacral Interaction  (Click on the title for an HTML version of a manuscript eventually published in the Journal of the American Academy of Osteopathy [AAO Journal 6(4):15- 21, 1996].  This is a summary report of several years' worth of research, describing the difficulties encountered in establishing interexaminer reliability for CRI measurement and discussing results which contradict the claim of interaction between the cranial and sacrum.)
Abstract:  Current understanding of the primary respiratory mechanism includes the concept of a linkage between the movements of the cranium and the sacrum via the spinal dura. To test this model for craniosacral interaction, methods were developed to document and analyze the timing of cranial and sacral cycles in healthy human subjects. A dual examiner protocol was utilized for a portion of this study, in which two examiners, one at the cranium and one at the sacrum, could simultaneously and independently document the cranial mechanism. A significant correlation was found between cranial and sacral cycle lengths documented separately by individual examiners, but pairs of examiners monitoring cranial and sacral cycle lengths of subjects simultaneously did not agree. These findings support predictions of the tissue pressure, or interactive, model for the cranial rhythm and do not support the concept of cranio-sacral interaction as described in the osteopathic literature.

Other Relevant Publications

JAMA editorial entitled "Alternative Medicine meets Science", JAMA 280(18):1618-1619, 1998.

British Columbia Office of Health Technology Assessment  report entitled "A Systematic Review and Critical Appraisal of the Scientific Evidence on Craniosacral Therapy", BCOTHA 99:1J 

Kinsel, JF, and SE Straus.  Complementary and alternative therapeutics: rigorous research is needed to support claims.  Annu. Rev. Pharmacol. Toxicol. 43:463-484, 2003.  

Ferguson, A.  A review of the physiology of cranial osteopathy.  Journal of Osteopathic Medicine 6(2):74-88, 2003.  

Sommerfeld, P, A Kaider, and P Klein.  Inter- and intraexaminer reliability in palpation of the "primary respiratory mechanism" within the "cranial concept".  Manual Therapy 9:22-29, 2004.