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(Recherche sur la technique de Méditation
Transcendantale au sein de l'armée de l'air suédoise)
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(Forschung über Transzendentale Meditation
bei der Schwedischen Luftwaffe)

Research on Transcendental Meditation at the Swedish Air force

Sensitive test for selection of pilots indicates
profound effects on mental health

By Jaan Suurküla M.D.


Swedish Air force pilots were examined with a test for selecting combat pilots in order to investigate the effects of Transcendental Meditation (TM). This test indicates Stress tolerance. They all underwent, without a single exception, improvements in one year that the best available psychotherapies can achieve only after about 20 times longer time or more - and only so in the best case.

The result also indicates that TM can improve performance significantly under psychologically highly demanding conditions. Also, it indicates that TM can considerably improve stress tolerance in stress-prone people as DMT-Neuman measures a key factor in stress proneness.

Differently from common stress treatment and prevention methods, TM apparently affects the fundamental causes of stress sensitivity.


A great problem in combat pilot training all over the world has been that psychological tests have not been able to reveal the deeply seated disturbances that make persons unable to keep the head cool in highly stressful situations. In Sweden, a major part (up to 80%) of the pilot trainees failed year after year. With few exceptions, the reason was psychological inaptitude revealed under demanding flight situations. The situation has been similar in other air forces, which meant great economic losses considering the high costs of pilot training.

Therefore the Swedish Air force sponsored the development of a test designed to reveal hidden psychological disturbances. The test used was the "Defence Mechanism Test" (DMT) originally created by Ulf Kragh. It was modified in important respects by the psychologist Thomas Neuman and was introduced in the Air Force 1970. As there are fundamental differences between Kragh's method and the way Neuman applies it, we will call it "DMT-Neuman".

Defence Mechanism Test (DMT) ad modum Neuman

This test turned out to be very reliable with a high correlation between the test points and inadequate behaviour or mistakes in demanding flight situations. Since the test was introduced in combat pilot selection, very few incidents or crashes have occurred due to psychologically inadequate pilot behaviour according to the Air Force (1). The same is the experience from the other air forces that now are using this test for selection of combat pilots (for more, see footnote 1).

DMT-Neuman is an unusally sensitive and reliable method for detecting deeply rooted disturbances in the psychology, greatly superior to MMPI and other common tests for revealing such disturbances. The most important reason is that, differently from such tests, it does not depend on verbal responses to questions.

Instead, DMT-Neuman detects disturbances in the perception of threatening pictures presented in a fraction of a second. It is experienced as a very brief flash that one only gets a very vague idea about. This is called subliminal perception. Persons with pronounced defence mechanisms react spontaneously with anxiety (indicated a/o by pronounced galvanic skin responses etc) that makes them distort what they perceive.

DMT-Neuman reveals deep-seated disturbances

According to psychology, the proneness to use psychological defence mechanisms in threatening situations is closely related to the presence of deeply seated, often early acquired memories of anxiety-provoking and otherwise traumatic or insecurity-causing experiences. These memories uphold an increased level of conscious or often subconscious anxiety. When a situation somehow appears threatening to such a person, this anxiety tends to break through. The defence mechanisms have the function to suppress these anxiety provoking impressions. So differently from secure and harmonious people who perceive the threat realistically and handle it adequately, the traumatized person immediately mobilizes reality-distorting defence mechanisms.

Remarkably common

Experience from DMT-Neuman studies has objectively verified psychological experience that most people with these disturbances usually behave completely normally except for in very demanding threatening situations. Extensive testing indicates that only a small percentage of the population is free from such defence mechanism activating disturbances. Massive experience from psychotherapy has shown that it takes often 20-25 years or more of psychotherapy to access and cure these deeply seated subconscious anxiety upholding disturbances.


DMT-Neuman research on subjects practising Transcendental Meditation

1. Pilot study

Pilots who were found to have pathologically high DMT-Neuman points (risk category 4) were grounded. The Air force wanted to recover these pilots but they had been informed that the disturbances that DMT-Neuman indicated were such that it would take too many years with the best psychotherapy methods to cure them. An Air force officer, involved in the DMT-Neuman project, contacted the undersigned, who then was the medical advisor of the TM movement. The officer asked if I had some experience about the effects of TM on such disturbances and wondered if TM might promote a more rapid cure. I told him that, against my experience of considerable improvement in a number of cases with serious anxiety problems, I was certain that one year would be enough to produce a significant improvement in the grounded pilots. Five of these, who were eager to regain flight duty, were encouraged by the Air force officer in charge of the project to start TM.

After one year, the pilots were retested by Thomas Neuman. In all five he found pronounced improvement, from the highest risk group (IV) to the lowest risk group (I). Neuman commented that the result was sensational considering that the serious and profound disturbances the test revealed in these five cases takes decades of psychotherapy to improve.

2. Controlled study

Although the test was designed to reveal stable deep-seated disturbances, the question arose if there was a flaw in the test considering the dramatic improvement after one year of TM. So the Air Force set out a program to investigate whether DMT-Neuman might sometimes give errors, measuring more superficial and temporary disturbances.

Part of this program was to make a one year controlled study with TM (2). A group of 15 persons who had failed at Air Force pilot selection due to high DMT-Neuman scores was used. Eight of them were instructed in TM and seven were controls. The average DMT-Neuman score was similar in both groups (slightly higher among controls).

At retesting after one year, the DMT-Neuman scores of the control group were unchanged. The scores of the TM group had improved at an average with about ten points. See diagram below:

DMT results

Additional retesting studies were made, all confirming that DMT-Neuman detected a stable trait unless the persons did TM.

The conclusion was that TM has indeed a considerable positive and profound effect on deep-seated anxiety causing personality disturbances (trait anxiety). Neuman also concluded that TM would be of great valuable as a preventive measure for ensuring optimal psychological health in Air Force pilots. The introduction of TM as part of the standard training of pilots was therefore recommended by the Four Star Air Force Colonel Hedberg, responsible for national military flight security. But for reasons other than scientific, the High Commander of the Air Force did not decide to integrate TM in the training.


Altogether 13 persons were tested with DMT-Neuman by the Air force. They all underwent, without a single exception, improvements in one year that the best available psychotherapies can achieve only after about 20 times longer time or more - and only so in the best case. This result is unprecedented in the history of psychology as such rapid improvement never has been achieved for this kind of deeply engrained disturbances.

The result also indicates that TM can improve performance significantly under psychologically highly demanding conditions. Also, it indicates that TM can considerably improve stress tolerance in stress-prone people as DMT-Neuman measures a key factor in stress proneness. Differently from common stress treatment and prevention methods, TM apparently affects the fundamental causes of stress sensitivity.

The healing of profound psychological disturbances indicated by the DMT-Neuman study concurs well with other results indicating profound and rapid positive effects of TM on the psychology in cases where conventional methods have been ineffective. This includes considerable improvement of Chronic Post-Traumatic Stress Disorder in Vietnam veterans (4) and considerably reduced recidivism and reduced violence in severe criminals (5, 6). The reason for this remarkable effectiveness seems to be that TM acts on a profound level, apparently transforming the neurophysiological basis for psychological disturbances. A neurophysiological transformation towards higher integration of brain functioning is indicated by improvement of brain wave coherence (7, 8, 9, 10, 11) and alteration of Sensory Evoked Potentials (12).

As the TM technique differs in important respects from meditation techniques and common stress reduction methods, there is no scientific basis for assuming that these results are applicable for other methods.

Acknowledgement: I want to thank Air Force Colonel Lieutenant Folke P Sandahl, who supervised the Air Force DMT development project, for checking and confirming the correctness of this manuscript and for valuable suggestions and advice.


  1. The validity of Neuman's interpretation method

    Ulf Kragh, the inventor of DMT suggested the responses to subliminally presented threatening pictures could be interpreted as projections of psychological states of the subject. However it is difficult to reliably establish the psychological significance of a certain response.

    Because of this, Neuman avoided any evaluation of psychological states with his version of DMT. His mission was to develop a stringent quantitative test for selection of Air Force pilots. The Air Force demanded it should have a high reliability and validity. To achieve this, Neuman found it was useful to assess only the presence of Defense Mechanisms. The number of different Defense Mechanisms present and some other stringently quantifiable criteria were used for calculating test points.

    In a systematic manner, Neumann developed his evaluation method using mistakes in combat pilot performance as the criterium of validity. He arrived at a correlation above 0,7 between the test points and error-proneness in pilot performance. The validity of this method has been further confirmed in extensive practical use in the Swedish and other air forces. Since the introduction of the test, there has been a very great decrease (to almost zero) of accidents and incidents found to be caused by pilot mistakes. Furthermore, formerly about 55-80% of the pilot trainees failed during training due to inappropriate flight behavior (making mistakes in stressful situations). But after the test was introduced 30 years ago, not a single Swedish pilot trainee has been discarded for this reason, although the pilot trainers systematically expose them for the same stressful situations that made a major part of trainees drop out formerly.

    Neuman did additional in-depth studies that further confirmed the validity of his method, demonstrating the connection between presence of defence mechanisms as revealed by his test and traumatic memories. He found that TM first normalized responses associated with recent traumatic memories and then gradually worked backward in the "record" of traumas. Unfortunately, the Air Force decided these reports should be confidential as they revealed intimate personal details of the subjects, some of whom still are active in the Air Force. In assessing anxiety he did not use projective psychology interpretations but objective criteria like galvanic skin responses.

    Conclusion: While the Kragh system uses a projective test approach for assessing the psychological response with important uncertainities due to interpretation problems, DMT-Neuman is a scientifically stringent quantitative method determining the amount of defense mechanisms with a high level of validity and reliability.


1. Sandahl, F.P.: The Defence Mechanism Test DMT as a Selection Instrument when Testing Applicants for Training as Military Pilots. Stockholm: Kungl Krigsvetenskapsakademiens Handlingar och Tidskrift (Proceedings and Journal of the Swedish Military Academy) nr 4, p 132-154, 1988.

2. Sandahl, F.P.: Inverkan av tm-utövning på neurotiseringsgrad. Stockholm: Läkartidningen (Journal of the Swedish Medical Association), vol 77, nr 34, p 2808 ff, 1980. (Swedish)

3. Eppley, K.R., Abrams, A.I., and Shear, J. Differential effects of relaxation techniques on trait anxiety: A meta-analysis. Journal of Clinical Psychology, 45(6), 957-974, 1989.

4. Brooks JS, Scarano T; Transcendental Meditation in the treatment of Post-Vietnam Adjustment. Journal of Counselling and Development 65:212-215. 1985.

5. Bleick CR, Abrams AI; The Transcendental Meditation Program and Criminal Recidivism in California, Journal of Criminal Justice 15:211-230, 1987.

6. Abrams AJ, Siegel LM, The Transcendental Meditation Program and rehabilitation at Folsom state prison: A cross validation study; Criminal Justice and behaviour 5:3-20, 1978; ALEXANDER CN, Doktorsavh vid Harvard University: "Ego development, personality and behavioural change in inmates practicing the Transcendental Meditation Technique or participating in other programs: A crossectional and longitudinal study. Dissertation Abstracts International 43:539B, 1982

7. Levine, P. Proceedings of the San Diego Biomedical Symposium sid 15 ff, 1976.

8. Dillbeck MC, Bronson EC, International Journal of Neuroscience 14:147-151, 1981.

9. Orme-Johnson DW et al Scientific Research on the Transcendental Meditation Program, Collected Papers vol 3:215, Vlodrop, Holland, MVU Press, 1989.

10. NIDICH R et al, Scientific Research on the Transcendental Meditation Program, Collected Papers vol 4, Vlodrop, Holland, MVU Press, 1989, 2273-2277.

11. TRAVIS, F. T. Eyes open and TM EEG patterns after one and eight years of TM practice. Psychophysiology 28(3a): S58, (Abstract), 1991.

12. LYUBIMOV, N. N. Mobilization of the hidden reserves of the brain. Program Abstracts of the 2nd Russian-Swedish Symposium "New Research in Neurobiology," Brain Research Institute, Russian Academy of Medical Sciences, Moscow, May 19-21, 1992.

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