What is Meditation?
In its simplest form, meditation is a practice of quietly observing the present moment. The “present moment” refers to both the outer world of sensory experience (e.g. sights, smells, body sensations), as well as the inner world of the mind (e.g. thoughts, beliefs, emotions). Meditation is not inherently religious; it does not require one to subscribe to a specific set of beliefs. There are many forms of meditation, but most focus on the breath as a way to anchor one’s conscious attention to the present moment.
Breathing Meditation is often used to elicit qualitative improvements in wellbeing, such as a stilling of the body and the mind, but there are also distinct physiological improvements. Contemporary research suggests that the practice of Breathing Meditation can physiologically affect the body to quantitatively improve:
- Glycemic control in individuals with type II diabetes [1,2]
- Heart rate variability (an indicator of the body’s ability to adapt to stress) [3,4,5]
- Brain function in individuals who’ve previously suffered from major depressive episodes 
- Blood pressure in pre-hypertensive adolescents 
While physiological improvements are impressive, it is important not to dismiss the psychological states that Breathing Meditation can qualitatively improve, such as:
- Anxiety [8,9,10,11]
- Depression [6,12,13]
- Rumination [12,13]
The Relationship between Physiology and Psychology
It should be noted that physiology (i.e. bodily function) and psychology (i.e. beliefs, thoughts, perspectives, and emotions) are not two distinct realms that operate independently from one another, but rather, they operate interdependently. The contents and patterns of the mind can shape the way the body functions, and vice versa.
An example of physiology affecting psychology:
- If one receives a high dose of caffeine from drinking too much coffee, there will be a significant release of the stress hormones cortisol  and epinephrine  into the blood stream. As a result of these hormones circulating in the blood, there will be an increase in heart rate, respiratory rate, blood pressure, sensory sensitivity, and threat perception. There is nothing inherently dangerous or threatening about drinking a large cup of coffee, yet, doing so can cause certain individuals to become gripped by a state of deep anxiety due to the acute physiological shift caused by caffeine.
An example of psychology affecting physiology:
- Ruminating on a stressful thought, such as speaking in front of a crowd of strangers, can elicit a release of the same stress hormones mentioned in the previous example (cortisol and epinephrine) [1,16,17]. Again, there will be an increase in heart rate, respiratory rate, blood pressure, sensory sensitivity, and threat perception. In this case, a completely imaginary situation, in which there is no actual physical threat, can cause an acute physiological response.
Types of Breathing Meditation
There are two basic types of Breathing Meditation that will be discussed in this article:
1.) Mindfulness Breathing Meditation (MBM)
- Attention is directed towards the breath, without forcibly alerting it on a conscious level. Breathing will likely slow down, but as a result of shifts in the nervous system instead of conscious control.
- Whenever you recognize that your mind has been wandering, bring your attention back to the breath.
- Objectively view the formation and dissolution of your thoughts, without feeling responsible for them, and without judging them as “good” or “bad”.
- Note the emotional responses to your thoughts. Do your thoughts impulsively make you feel happy, sad, angry, frustrated, hopeless, or excited? Again, avoid judgement. Avoid viewing your emotional responses as “good” or “bad”.
- "Mindfulness is rooted in Eastern meditation tradition and can be characterized as paying attention in a certain way— on purpose, in the present moment, and nonjudgmentally."  – John Kabat-Zinn
2.) Diaphragmatic Breathing Meditation (DBM)
- The diaphragm is consciously engaged in order to fully expand the lungs.
- Breathing is performed in a slow and controlled manner. To accomplish this, air is typically inhaled through the nose and exhaled through pursed lips.
- Attention is directed towards the sensation of the belly expanding and collapsing during breathing.
- During inhalation and exhalation, there is a visually recognizable expansion and collapse of the belly, respectively.
Meditation is meant to be simple; it is about focusing on the immediate experience. Therefore, concerning yourself with abstract ideas about “what meditation is supposed to be” or “what meditation is supposed to do” will only hinder the practice. Keep in mind that Mindfulness Breathing Meditation and Diaphragmatic Breathing Meditation do not have to be mutually exclusive in every respect. For example, you can still use the mindfulness approach when breathing slowly with the diaphragm.
You may wonder, “what kind of meditation is best?” The answer to that is: whatever kind appeals to you the most, because that is the kind you are most likely to do on a regular basis.
The Consequences of Chronic Stress
Before I go into how Breathing Meditation can help manage stress, I will explain what stress is, and why it is important to manage it.
Outside of scientific research, “stress” tends to be an ambiguous term, and even in the realm of science, “stress” has a range of definitions. But put into its simplest terms, stress is something that brings your body outside of its normal balance. As a result, stress requires a response (physical, psychological, or both), in order to return the body to balance.
An Example of Physical Stress
- If you go for a walk on a 100 degree day, you will experience a heat stress that will require your body to make a change (i.e. adapt) in order to maintain a healthy core temperature. So as a result, you will start to sweat, and the water on the surface of your skin will absorb your own body heat and evaporate, effectively cooling your body (assuming it’s a dry day). If you keep sweating for a prolonged period of time, your blood volume will decrease notably, and you’ll have another homeostatic perturbation on your hands. Your body will respond by eliciting the sensation of thirst, so that you will drink water and restore your blood volume to a healthy level. In this chain of events, your body smoothly orchestrates several physiological processes in order to maintain a healthy balance when faced with stress.
An Example of Psychological Stress
- You are lazily walking through the woods, lost in a daydream, when a strong storm suddenly passes over you. The trees around you start violently bending and creaking. You imagine a huge tree falling on you. This frightful idea causes your body to release stress hormones that increase available energy in the blood, and make you hypervigilant of your surroundings. You continue to walk through the woods, but on high alert. After some time passes, despite the deafening sound of blowing wind and pouring rain, you hear a crack and a rushing noise behind you, which you easily hear because of your heightened senses. Due to the concentration of available energy in your blood, you are able to sprint away before a huge tree falls on you.
In both of these cases, you can see that stress is not inherently a bad thing. Stress is part of life. In fact, the body needs to experience a healthy amount of stress in order to survive and flourish.
Stress makes the body more resilient:
- Lifting weights causes the body to adapt and become stronger
- Exercising in a hot environment causes the body to adapt to become more efficient in cooling itself
- Exposure to bacteria causes the body to adapt and strengthen its immune system
Stress also makes the mind more resilient:
- Immersing yourself in a psychologically challenging situation (e.g. sports competition, public speaking, taking an exam) increases your ability to cope with the psychological stress of that situation
- In obsessive compulsive disorder (OCD) specifically, one of the most effective treatments is actually exposing the patient to gradually more stressful situations, so that they can learn to better cope with their fears 
So if stress makes you more resilient, why is it a problem that needs to be managed? Stress is not the problem, chronic stress is, and in our particular culture, chronic psychological stress. We live in an environment that differs greatly than the one we evolved to flourish in. We now have a dense population, commutes (across land, water, and air), bills, deadlines, rigid & unhealthy cultural expectations, highly advanced warfare, inundation of advertisements, global concerns, and endless complications – all things that increase the frequency at which we become stressed.
Luckily, humans are highly adaptive organisms that can learn to cope in a variety of environments. However, we still carry physiological and psychological baggage that we evolutionarily collected from living in raw nature for most of our species’ history. Humans aren’t wired to effectively cope with the abstract psychological stresses of modern society. As a result, we are likely to experience the repeated activation of the sympathetic nervous system.
Sympathetic Nervous System (SNS) – A component of the nervous system that is responsible for helping you evade a threat. Activation of the SNS increases: heart rate, respiratory rate, blood pressure, availability of usable energy, sensory sensitivity, and threat perception (i.e. vigilance). Activation of the SNS decreases blood flow to digestive organs. SNS activation is commonly known as the “fight or flight” response.
Parasympathetic Nervous System (PNS) – A component of the nervous system that is responsible for facilitating digestion and recovery. Activation of the PNS decreases: heart rate, respiratory rate, blood pressure, availability of usable energy, sensory sensitivity, and threat perception (i.e. vigilance). Activation of the PNS increases blood flow to digestive organs and encourages tissue recovery. Activation of the PNS elicits a state of “rest and digest”.
Reciprocal Relationship between SNS and PNS – As you may have surmised, the SNS and PNS, more or less, elicit opposite effects on the body. The ability to switch back and forth from SNS dominance and PNS dominance is a sign of a healthy nervous system that can effectively adapt to stress. Problems occur if either the SNS or PNS become overactive. This article addresses what happens when the SNS gets “stuck” in the “on position”.
The SNS does not recognize the difference between imminent physical threats and frightening abstract ideas [10,17]. So whether you are walking across a pond covered in thin ice, or worrying about losing your health insurance coverage, your SNS will respond in the same way. As previously mentioned, our society offers a wealth of things to be psychologically stressed about, leading many individuals to experience frequent activation of the SNS.
Frequent activation of the SNS over a prolonged period of time (i.e. chronic stress) increases the risk of:
- Heart attack 
- Stroke 
- Type II diabetes 
- Cardiovascular disease 
- Hypertension 
- Dyslipidemia 
- Obesity [17,20,21,22]
- Insomnia 
- Depression 
- Anxiety disorders 
In addition, frequent activation of the SNS can lead to chronic hyperventilation. Chronic hyperventilation negatively affects blood chemistry and neuronal function, which can result in increased muscle tension, irritability, and sensitivity to light, sound, and pain .
Now the pressing question is: how does one learn to cope with stress?
Breathing Meditation and Stress Management
The goal of stress management is to reduce the frequency and intensity of the SNS response. In other words, you want to activate the SNS less often, and you want those activations to be less powerful. This means you will want to avoid unnecessarily stressful situations (e.g. watching the news before bed), and also learn to better respond to unavoidable stressful situations (e.g. commuting in traffic).
In order to make the necessary changes to reduce the frequency and intensity of the SNS response, you must:
- Increase your awareness of the thoughts and feelings that lead to a stress-response
- For example, some people react to making a mistake by spiraling into negative self-judgement (thoughts) and anger (feelings), which elicits an SNS response.
- Objectively examine your lifestyle and “mindstyle” in order to identify behaviors and thought patterns that tend to cause unnecessary stress.
- Example of an unnecessary thought pattern: Some people may find themselves reliving events long-past about which they felt dissatisfied, angry, or embarrassed. This is an unnecessary stress, since there is nothing that can be done about the past.
- Example of an unnecessary behavior: Some people find themselves in a perpetual state of frantic rushing due to poor time management.
- Example of an unnecessary thought pattern: Some people may find themselves reliving events long-past about which they felt dissatisfied, angry, or embarrassed. This is an unnecessary stress, since there is nothing that can be done about the past.
The key concept here is awareness, for you cannot solve a problem that you do not know exists.
Mindfulness Breathing Meditation helps manage stress by:
- Increasing internal awareness so that one can recognize negative thoughts and feelings that lead to a stress-response 
- Decreasing negative thinking [4,9,12]
- Improving mood 
- Increasing the ability to cope with anxiety 
- Reducing SNS activity and increasing PNS activity 
- Increasing heart rate variability (an indicator of the body’s ability to adapt to stress) [3,4,5]
Diaphragmatic Breathing Meditation helps manage stress by:
- Reducing SNS activity and increasing PNS activity [1,5,24]
- Decreasing anxiety 
- Increasing heart rate variability 
SNS Activation and Threat Perception
As previously mentioned, activation of the SNS increases threat perception (i.e. vigilance). Being able to better perceive threats, immediate or potential, is an important survival mechanism.
Here are some examples:
- You are going to hike through a jungle that you know is infested with highly venomous snakes. Due to anticipation of a threat (i.e. venomous snake bite), your SNS activates, increasing sensitivity to sensory input so that you are better able to detect sights, sounds, and tactile sensations that could be a snake.
- You are calmly hiking down a mountain trail, nearing your car. A grizzly bear suddenly charges you from a distance. Due to the immediate threat, your SNS activates, flooding your blood stream with stress hormones and immediately-usable energy, allowing you to sprint to your car as quickly as possible.
If you didn’t have a strong SNS response in either of these situations, you would be less likely to survive them. The SNS helps protect you from imminent physical threats. After the threat is avoided, SNS activity decreases, and you carry on in a relatively stress-free manner.
However, imminent physical threats are not common in the modern world. Yet, due to chronic psychological stress, many humans still experience the same SNS response as if there were a chronic physical threat, making them experience the world with a heightened threat perception. In other words, the world is perceived through a lens of fear. As a result, many of us go about our days anxiously, anticipating some sort of impending danger, whether we realize it or not. If we can’t pinpoint something that is dangerous, we project our fear out into the world, leading us to tendencies of control, suspicion, and insecurity. With an overactive SNS, you are more likely to assume people, places, and things as dangerous or threatening in some way (you’re always waiting for the other shoe to drop).
The practice of Breathing Meditation can reduce SNS activity and increase PNS activity [1,5,24], causing a reduction in threat perception and anxiety [8,9,10,11]. Breathing Meditation increases the ability to see the world without fixating on unreasonable fears; it helps one to become more aware of positive possibilities, instead of negative ones. One sees life through a different lens than that of fear. Perceptions shape beliefs, and beliefs shape behavior. Since Breathing Meditation alters perceptions, there are powerful implications for behavior change.
Breathing Meditation and Responding vs. Reacting
Breathing Meditation increases your ability to respond to a stress, instead of reacting to it. There are some semantics involved here, so some definitions will be helpful:
Response ► A decision made from conscious intent and an awareness of one’s emotional state
Reaction ► An impulsive reflex driven by negative emotions
Here’s an example:
A man spills a cup of coffee on a white rug and immediately realizes that a mistake has been made which can’t be undone. Instead of getting upset, he decides to calmly clean up the mess. The man is able to remain calm because he has a keen awareness of his inner emotional state after spilling the coffee. He is able to occupy a mental space where he sees two potential paths.
- Path 1: Reaction
- Engage with the negative emotions (i.e. anger, frustration, and self-criticism) that spring from the mind impulsively, thus activating the SNS and effectively ruining his mood for the following few hours.
- Path 2: Response
- Realize the “bubbling up” of the negative emotions, and decide to direct attention towards what can be done to clean up the mess, instead of ruminating on the fact that a mistake has been made.
The man chose path 2 (responding), because he realizes that engaging with his negative emotions is a completely fruitless decision that only leads to a stress-response, continued negative thinking, and likely another silly mistake.
Attaching to, engaging with, or paying attention to negative emotions tends to prolong and intensify them. Individuals who consistently practice MBM are better at regulating their attention and disengaging from negative thinking [3,13]. Consistent meditation grants you a “buffer” against negative thoughts and emotional impulses, allowing you a space to consider your options so that you can choose to respond to stressful situations, instead of reacting to them. This is, in my opinion, one of the most profound benefits of meditation for stress management.
Avoidable and Unavoidable Stress
MBM can help you achieve an objective perspective on your lifestyle, making it possible to recognize unnecessary stresses. A consistent practice of MBM can increase your ability to detect when negative emotional impulses arise, so that you can recognize what triggers them. For example, if you notice yourself getting stressed out when you watch the nightly news before bed, you have recognized a stress trigger, and you can then simply cut that unnecessary habit from your life.
While avoiding unnecessarily stressful situations is an effective method in stress management, not all stressful situations can, or should, be avoided. Life inherently involves unavoidable stress. To avoid all stress is to avoid life. The avoidance of stressful situations (both external and internal), or situations perceived to be stressful, is one of the hallmarks of anxiety disorders . Those with anxiety disorders often get caught in a positive feedback loop of:
- Stress that leads to fear.
- Fear that leads to avoidance of stressful situations (real or perceived).
- Avoidance that weakens the ability to cope with stressful situations.
- The inability to cope with unavoidable stressful situations leads to more stress.
- Stress leads to fear, and the cycle continues, slowly degrading the anxious individual’s ability to cope with stress so that he/she gradually retreats from normal life activities.
Positive Feedback Loop of Fear and Avoidance
This is the sort of loop that those with anxiety disorders commonly experience. MBM can help break the cycle of negative thinking [4,12], catastrophizing of stressful situations , and avoidance behavior , helping those with anxiety disorders to better cope with stress. Coping with stress is an adaptive skill; it weakens with lack of use, and becomes stronger when used.
The Unique Merits of Breathing Meditation
Breathing Meditation is remarkably cost effective because its physiological and psychological benefits have been scientifically validated, and it is free . Not only that, but you can perform Breathing Meditation in nearly any situation, as it just requires attention to the breath (something that is always occurring within you). You always have the ability to focus on, or slow, your breathing while paying attention to the present moment.
In summary, Breathing Meditation is:
- Effective in reducing stress
Negative Effects of Meditation
The negative effects of meditation are very limited . However, there have been a few reports of individuals experiencing psychotic or manic events when overusing or misusing meditation, but these individuals either had, or likely had, previously existing psychiatric disorders [27,28].
Limitations in Studying Meditation
The scientific study of meditation examines the complex relationship between psychology, behavior, and physiology, making it difficult to pinpoint causal mechanisms. In other words, it’s hard to specifically claim that “x-kind of meditation causes y-effects”. The study of meditation, and even physiology, is much more “fuzzy” than, say, physics. Contemporary meditation research looks to understand the effects of meditation by measuring quantitative physiological factors, such as brain wave activity, blood pressure, heart rate, heart rate variability, respiratory rate, hormone & neurotransmitter secretion, and indicators of glycemic control (i.e. insulin, blood glucose, and HbA1c), as well as qualitative factors associated with anxiety and depression.
Intervention-Repeatability and Compliance:
The individual’s interaction with meditation is highly variable. Therefore, it is challenging to reliably give different study-participants the same meditation intervention (i.e. trans-participant intervention-repeatability), and a single participant the same meditation intervention recurrently over time (i.e. inter-participant intervention-repeatability). A meditation intervention is different than, say, giving each participant a 100 mg pill of caffeine, and then studying the physiological changes that occur. Meditation cannot be “dosed” in a highly controlled and precise fashion.
It is also difficult to ensure that all study-participants are complying with a study’s prescribed meditation intervention. When a group of individuals meditate, they can all look the same to the outside observer, but the inner processes of attention regulation and breath control can be quite different between the individuals.
Studies on meditation tend to have a small sample size (i.e. a small amount of people participating in the studies). Due to this, it can be difficult to extrapolate the results of the study to the general population.
New Field of Research:
The scientific study of meditation is a relatively new field, so there is still much to be learned in the design and implementation of experiments investigating the effects of meditation.
A common sentiment regarding stress is, “it’s all in your head”. While stress influences the psyche (and vice versa), stress is not exclusively “in the head”; it’s also in the body. Stress, regardless of its origin, alters the body’s physiology due to activation of the sympathetic nervous system (SNS). Chronic stress, and the consequential frequent activation of the SNS, increase the risk of several diseases and disorders. Therefore, the ability to effectively cope with stress is an essential skill for healthy living.
Forms of Breathing Meditation, such as Mindfulness Breathing Meditation (MBM) and Diaphragmatic Breathing Meditation (DBM) can play a powerful role in the management of stress by decreasing both the frequency and intensity of the SNS stress-response. The ability to shift one’s attention towards the breath is always accessible, making Breathing Meditation an excellent method for managing stress.
Breathing Meditation for Stress Management is:
- Virtually devoid of negative side effects
Why Zebras Don’t Get Ulcers by Robert M. Sapolsky (one of the most informative and easy-to-read books about the physiology of stress, how chronic stress increases the risk of disease, and how to cope with stress.)
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