Persinger, Michael A, Norman J. Carrey and Lynn A. Suess. TM and Cult Mania (198 pages). North Quincy, Massachusetts: Christopher Publishing House, 1980.*

"Critiques TM-movement research up until 1980; alerts the reader to question the validity of more recent movement research; discloses that the state of cosmic consciousness described by Maharishi Mahesh Yogi shares characteristics of some personality disorders." (résumé)
Persinger, M.A. (1993). Transcendental Meditation and general meditation are associated with enhanced complex partial epileptic-like signs: evidence for 'cognitive' kindling? Perceptual and Motor Skills, 76, 80-82.* [Extraits] [cat.inist.fr]
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"Personal Philosophy Inventories of 221 university students who had learned to meditate (about 65% to 70% practiced transcendental meditation) were compared to 860 nonmeditators. Meditators displayed a significantly wider range of complex partial epileptic-like signs. Experience of vibrations, hearing one's name called, paranormal phenomena, profound meaning from reading poetry/prose and religious phenomenology were particularly frequent among meditators. Numbers of years of TM practice were significantly correlated with the incidence of complex partial signs and sensed presences but not with control, olfactory, or perseverative experiences. The results support the hypothesis that procedures which promote cognitive kindling enhance complex partial epileptic-like signs." (résumé)