In my opinion, meditation should be appreciated as a resource but should never, ever have the effect of becoming addictive, or of estranging a practitioner from friends, family or activities he or she has formerly enjoyed.
At most, a meditator may choose to live a less hectic life, but if the practice is healthy, it should be apparent that the person has retained a capacity to enjoy themselves, and continue to relish activities he or she enjoyed before becoming a practitioner. And even if a practitioner decides to live more quietly than before, he or she should retain social skills and have the ability to socialize with a wide range of people if necessary.
A reputable meditation teacher would also tell you who is likely to benefit from meditation and which people should avoid it. A good teacher will also tell you the exact indications that you're over-doing meditation and need to back off, just as a coach teaches athletes how to spot signs of over-training and when reduce training load until one has recovered.
Once, I asked my therapist whether there are people who should avoid Zen meditation or Insight Meditation/Vipassana. (These methods do [u:4d452761cd]not [/u:4d452761cd]aim at producing bliss states, and you're actually supposed to [u:4d452761cd]avoid [/u:4d452761cd]seeking any kind of result. There is no marathon chanting, and no hyperventilation--making Zen and Insight meditation quite different from TM and the various 'shakti/kundalini' practices). At the Zen centerse, there is some some chanting as part of religious services, but these are chanted texts, not repetitive mantras)
My therapist said that many persons who are clinically depressed (that is, their depression has a strong biochemical component) would be well-advised to [i:4d452761cd]avoid [/i:4d452761cd]Zen & Insight meditation, especially long retreats, until they've been stabilized. If a person has untreated clinical depression, the ego-relaxation produced in Zen/Insight meditation could cause the person's depression to get worse.
*[i:4d452761cd]It is also a very good idea to start with just one day retreats, then try 2 or 3 day retreats and see how you respond, both during the retreat and then after you've returned home[/i:4d452761cd].
Persons with severe personality disorders (narcissistic personality disorder, borderline personality disorder) might also be at risk of suffering depression if they were to engage in a form of meditation that relaxed ego.
For persons with schizophrenia, ego-relaxing meditation is counter indicated.
One can do Zen/Insight meditation and participate quite successfully in multi-day retreats if one has bipolar disorder, but only if your condition is stable, you have taken full responsibility for your self care (which includes the right balance of sleep and diet)--and [i:4d452761cd]only [/i:4d452761cd]if you're on a combo of medication that works, and you're not trying to self-medicate on alchohol or street drugs.
(In Zen and Insight meditation, bed time is usually 9 pm to 4:30 or 5 am, usually with a 2 hour break in late afternoon. You'll be able to get enough sleep under these conditions, and if not, most places can accommodate people with medical concerns who need to sleep 1 to 2 hours later in the morning.
***ALERT [i:4d452761cd]It is not uncommon for persons on multi-day retreats to discover that they need less sleep. I've been on a number of multi-day retreats, and noticed that after about 3 days, most of us were getting up earlier and earlier, hours before we even had to get up. Even though we were doing quiet sitting meditation, just following breath and noting our thoughts and emotions, something about this apparently reduced our need for sleep. So, this could be an issue for persons with bipolar--if you're bipolar and consider doing a multi-day retreat, make sure to do it at a place where you can easily leave if you discover you're getting de-stabilized and need to go home. That means making very sure you have transportation arranged in advance![/i:4d452761cd]
Diet at these places is vegetarian. If you need a lot of protein, you must make sure to bring your own supply of protein powder with you. If they refuse to let you do this, go to another practice center)
At a well run meditation center, their intake form will ask whether you have any medical or emotional condition that could affect your ability to do the retreat, and if you're on any medications.
*With what we know today, NO reputable teacher or meditation center should ever claim or even hint that thier practice is harmless and beneficial to everyone. Not everyone is in sufficient condition to train for a triathlon, and not every person is in proper condition to undertake committed meditation practice. A good coach would never, ever tell someone with a chest cold 'You're ready to train for a marthon'--that coach would tell you to go home and go to bed until you've recovered.
In her book [i:4d452761cd]Call No Man Master [/i:4d452761cd](available on Amazon.com) Joyce Collins-Smith gave a detailed description of an 8 to 10 year period she spent as a dedicated practitioner of TM. She was also administrative assistant to Maharishi during his earliest years in London.
After she left Maharishi and stopped practicing TM, Collins-Smith plunged into a dangerous depression, and after she recovered, she found that after a lifetime as a fiction writer, she could no longer create stories. Only after many years could she resume a career as a writer, but could only write non-fiction. She was unable to resume her formerly enjoyable and lucrative career of writing novels.
Collins-Smith reported meeting other artists who took up TM and discovered they were unable to care about or enjoy the arts they'd formerly loved. And even in her early years with Maharishi, Collins-Smith noticed a very high turn over among the support staff: over time, meditators became passive, zoned out, inefficient - and had to be replaced!
Despite her grim description of the casualty rates among early TM practitioners, and the heavy price she herself paid for her devotion, Collins-Smith remained strangely forgiving of Maharishi, seeing him as having started with fundamentally good intentions, but in the end, corrupted by power.
She apparently could not give up her idealizion of MMY, despite what appears to be very clear evidence that he knew that his TM harmed people--and continued to push it.
In this article,
we have the following information:
'Of these biochemical changes, the implications for the increase in brain neurotransmitter, serotonin, are significant and wide-ranging in their potential negative consequences. (See TM & Serotonin: Model of Effects. )
Here are some of the biochemical alterations (abstracts below):
Increase in brain neurotransmitter, serotonin
Change in secretion and release of several pituitary hormones "similar to the effects of synthetic anxiolytic and tranquilizing agents such as benzodiazepines"
Increased AVP secretion
Loss of normal diurnal rhythm for the hormones ACTH and beta-endorphin
An increase of carbon dioxide
STUDY: Serotonin, noradrenaline, dopamine metabolites in transcendental meditation-technique. Bujatti M, Riederer P J: Neural Transm 1976;39(3):257-67
The highly significant increase of 5-HIAA (5-hydroxyindole-3-acetic acid) in Transcendental Meditation technique suggests systemic serotonin as "rest and fulfillment hormone" of deactivation-relaxation...
STUDY: Serum hormonal concentrations following transcendental meditation--potential role of gamma aminobutyric acid. Elias AN, Wilson AF Department of Medicine, University of California Medical Center, Irvine, Orange, USA: Med Hypotheses 1995 Apr;44(4):287-91
Transcendental mediation (TM) is a stylized form of physical and mental relaxation which is associated with changes in the secretion and release of several pituitary hormones. The hormonal changes induced by TM mimic the effects of the inhibitory neurotransmitter gamma aminobutyric acid (GABA). It is hypothesized that TM produces changes in pituitary hormone secretion by enhancing hypothalamic GABAergic tone, and its anxiolytic effects by promoting GABAergic tone in specific areas of the brain. This mechanism is similar to the effects of synthetic anxiolytic and tranquilizing agents such as benzodiazepines that bind to components of the GABA-A (GABAA) receptor. TM, therefore, may produce relaxation by enhancing the effects of an endogenous neurotransmitter analogous to the effects of endorphins in runners who reportedly experience a 'runner's high'.
STUDY: Hormonal control in a state of decreased activation: potentiation of arginine vasopressin secretion. O'Halloran JP, Jevning R, Wilson AF, Skowsky R, Walsh RN, Alexander C: Physiol Behav 1985 Oct;35(4):591-5
Behaviorally induced stress is associated with increased arginine vasopressin (AVP) secretion. In this report we describe a phasic conditioned response of AVP secretion yielding 2.6-7.1 times normal plasma concentration of this hormone in association with a physiological state of decreased activation, that associated with the mental technique of "transcendental meditation" (TM) in long-term practitioners (6-8 years of regular elicitation). Such a very large phasic response of AVP was previously unknown in the normal physiology of AVP.
STUDY: ACTH and beta-endorphin in transcendental meditation. Infante JR, Peran F, Martinez M, Roldan A, Poyatos R, Ruiz C, Samaniego F, Garrido F Clinical Analysis and Immunology Service, Virgen de las Nieves Hospital, Granada, Spain: Physiol Behav 1998 Jun 1;64(3):311-5
We have evaluated the effect of Transcendental Meditation (TM) on the hypothalamo-hypophyseal-adrenal axis diurnal rhythms through the determination of hormone levels. Blood samples were taken at 0900 hours. and at 2000 hours. These samples were taken from 18 healthy volunteers who regularly practice TM and from nine healthy non-meditators. Cortisol, beta-endorphin, and adrenocorticotropic hormone (ACTH) were measured at both hours. TM practitioners showed no diurnal rhythm for ACTH and for beta-endorphin (ACTH, pg/mL, mean +/- SE; 13.8+/-1.2 - 12.1+/-1.5/beta-endorphin, pg/mL; 14.4+/-1.5 - 17.2+/-1.9, at 0900 hours and 2000 hours, respectively), in contrast to control subjects, who showed normal diurnal rhythm for these hormones and for cortisol (ACTH, pg/mL; 19.4+/-1.9 - 11.9+/-2.2/beta-endorphin, pg/mL; 25.4+/-1.7 - 17.7+/-1.1/Cortisol, ng/mL; 201.4+/-13.2 - 71.3+/-6.5, at 0900-2000 hours, respectively, p < 0.01 in the three cases). Practitioners of TM with similar anxiety levels to those of the control group showed a different pattern in the daytime secretion of pituitary hormones. TM thus appears to have a significant effect on the neuroendocrine axis. Because cortisol levels had a normal pattern in the TM group, these results may be due to a change in feedback sensitivity caused by this mental technique.
STUDY: Behavioral alteration of plasma phenylalanine concentration. Jevning R, Pirkle HC, Wilson AF: Physiol Behav 1977 Nov;19(5):611-4
The concentration of 13 neutral and acidic plasma amino acids was measured before, during and after either 40 min of control relaxation or 40 min of the process known as transcendental meditation (TM). An electro-oculogram, electroencephalogram, and electromyogram were simultaneously monitored in these subjects. Increased phenylalanine concentration was noted during TM practice with no change during control relaxation; no difference between the groups of total time slept or sleep stage percent was observed. The stability of phenylalanine concentration in controls and lack of correlation of increased phenylalanine with sleep in the long-term practitioners seem to suggest a relationship of the phenylalanine increase to TM practice.
STUDY: Meditation and somatic arousal reduction. Holmes, David S: American Psychologist, January 1984, pp1-10. Ensuing discussion follows in four more issues: June 1985, pp717-731; June 1986, pp712-713; September 1986, pp1007-1009; September 1987, pp879-881.
... Meditating subjects were found to have higher levels of phenylalanine that resting subjects, a finding which reflects high arousal in meditators.
STUDY: Relaxation-induced anxiety: mechanism and theoretical implications. Heide, Frederick J. and Borkovec, T. D. Behavioral Research Therapy, 1984, pp1-12.
STUDY: Relaxation-induced anxiety enhancement due to relaxation training. Heide, Frederick J. and T.D. Borkovec. Journal of Consulting and Clinical Psychology, 1983, p171.
These two papers by Heide and Borkovec disclose that 54 percent of anxiety-prone subjects tested experienced increased anxiety during TM-like mantra meditation.
STUDY: Metabolic Rate, Respiratory Exchange Ratio and Apneas During [TM] Meditation. John Kesterson and Noah F. Clinch. The American Journal of Physiology, March 1989, R637.
A careful, in-depth investigation into the effects of TM practice on respiration and metabolism, revealing that TM produces no deeper state of rest than from just sitting with eyes closed, even in advanced practitioners, and that the TM practice does not produce a hypometabolic state as claimed by MIU's Robert Keith Wallace.
They also discovered a decrease in respiratory exchange ratio in meditators during TM not observed in controls (i.e., an increase of carbon dioxide). Although this research was conducted at MIU, Kesterson and Clinch maintained their objectivity. Unlike most work by TM movement research, this particular study was published in a major journal.