The lost art of joy – The freedom of now

How do drive your car?

We all have our own particular styles – cautious, sedate, zippy, or kamikazi. There are some drivers that drive like a tortoise on tranquillisers. I always seem to get stuck behind them at traffic lights. I would describe my driving style as ‘confident’, though when I quickly nip around them at the lights, I’m sure they would think I’m in too much of a hurry.

Whether we’re on a perpetual Sunday drive or we go like a bat out of hell, there are some commonalities to how we all drive. No one drives the whole journey looking in the rearview mirror and no one crawls along in first gear all the way just in case there might be a red light or a stop sign up ahead. When we’re in control of our car, we drive according to the conditions around us at the time.

In the first two posts of this series, we looked at acceptance and values, or as the Serenity Prayer says, “give me grace to accept with serenity the things that cannot be changed, Courage to change the things which should be changed, and the Wisdom to distinguish the one from the other.” Acceptance and values intersect in the present moment, the ‘now’.

We can’t change what has happened in the past, and we can’t control what is going to happen in our future. We can advance in the direction set by our values and embrace the freedom of living in the now.

Living in the now is just like driving. There’s no point looking in the rearview mirror the whole way. We can’t change the past. Getting lost in the if-only’s of the past means we don’t get to experience what is going on around us, and it effectively stops us moving forward because we’re looking the wrong way. We become stagnant and the lack of lack of forward progress makes it hard for joy to flourish. Neither can we control the future. Sometimes we allow the what-if’s of the inherently uncertain future to slow our progress and hold us back. We don’t know what’s around the bend, and after a while we prefer the familiarity of our rut.

When we move beyond the past and leave the future to our destiny, we can focus on the richness of the present moment. Living in the present moment is both liberating and invigorating – we are no longer being held captive by what has been or what might be, and we can allow our attention to absorb all of the plentiful and pleasing details that are going on all around us, every moment of our lives.

Living in the now is part of the practice of mindfulness. Mindfulness is a skill, and like every other skill, it takes some practice to get good at it. But the practice is worth it, as mindfulness is associated with higher levels of life satisfaction, agreeableness, conscientiousness, vitality, self esteem, empathy, sense of autonomy, competence, optimism, and pleasant affect.

There are many ways to practice mindfulness, but if you’re a novice, then a good place to start is through some apps like Smiling Mind or Headspace.  As you get better at living in the present moment, you will start to enjoy the richness and freedom that comes with it. If you start now, you won’t have to live haunted by the ghosts of Christmas-Past or Christmas-Future, but can have a marry and a mindful Christmas, living in the freedom of now.

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The Perspective of Dawn

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Perhaps it was the hypnogogic delirium, but I had an epiphany.

Truthfully, it was probably less epiphany and more of a reminder, that little “oh yeah” sort of moment.

Yesterday I was sitting in an airport lounge at 5am, waiting to be whisked away on my 6am flight to the tropical north to join my family and in-laws for Christmas.

For the life of me, I can’t remember why I decided to book a flight for six in the morning.  I think the flight was cheap, and I thought to myself “6am … that’s not that early …”.  I forgot that to allow for travel time and checking in, I had to get up at 3:30am.  Not even sparrows are awake at half-past three.  In fact, I’m often going to bed at that time of night, so this whole pre-dawn awakening thing was really foreign.

The fact that I was showered, dressed, and sitting at the airport compos mentis was really weird … I think I was slightly delirious.

Still, the whole predawn awakening thing was enlightening. It was a refreshing glimpse of a time of day that I normally spend hibernating. The first thing I noticed was the light. I always thought that dawn and dusk were the same but just lighting from the opposite direction, but there’s a subtle difference in the hue that gives the early morning a softer, fresher glow.

The other thing I noticed was the stillness.  Everyone else in their right mind didn’t book dawn flights and were still snug in their beds, so the usual hustle and busy buzzing that usually fills the streets was absent.

The soft cool breeze on my face, in the midst of the calmed half-light was almost meditative.  It was quite a change to my daily routine of sleeping until I have to drag myself (and the kids) out to our usual daytime occupations.

The stillness and beauty of my new perspective of dawn reminded me of how it’s easy to get stuck in the same pattern.

Our routines are partly a function of necessity – we have to go to work, the kids have to go to school, we have to get groceries, attend social functions, go to church on Sundays.  There isn’t anything necessarily wrong with this repetitive normality.  Still, our brain gets used to the usual patterns and it starts to filter out the same input that it gets continually exposed to, and our brains function on autopilot.  This process of automation, habituation and suppression is an advantage for our brains in terms of efficiency and energy conservation, but this leaves a bit of a cognitive void which our brain fills with the internal monologue of our own confabulation.  We drink our own kool-aid, as it were.

This is what people often think of as “the rut”, that existential inertia and stagnation, the first-world malaise of meaningless repetition.

The antidote to the rut is to break the pattern.  When we have a change to our circumstances and we experience something new, our brain has to process things differently.  More processing power is needed, which involves our working memory and our conscious stream of thought.  One small step outside the comfort zone of our routine, and all of a sudden, the world can seem fresh and new again.

This process is enhanced through mindfulness.  When we practice mindfulness, we fully engage in the present moment.  We can appreciate the detail that we so often filter out and ignore.  We can (and should) practice mindfulness at any time, but when we’re engaging in a new experience, immersing ourselves in it mindfully will only enhance it.

The perspective of dawn that I experienced yesterday helped remind me of the power of stillness in an ever-demanding world over-saturated with stimulation.

I hope that this Christmas and New Year, you can take the time to have your own ‘perspective of dawn’ as it were – step out of your comfort zone and experience something completely new, and engage with the experience fully, mindfully.  I hope you gain a fresh insight that you can help propel you forward into the amazing potential that 2017 holds for us all.

From my family to yours, have a very Merry Christmas and a safe and prosperous New Year.

Dr Caroline Leaf and the tongues trivia tall tales trifecta

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I saw a Facebook factoid from Caroline Leaf today that said, “When we speak in tongues, research shows that the areas involved in discernment in the brain increase in activity, which means we increase in wisdom.”

Dr Caroline Leaf is a communication pathologist and a self-titled cognitive neuroscientist. She has also proclaimed herself as an expert on science and the Bible.

In the opening of her “Scientific Philosophy”, for example, Dr Leaf says that, “God is the Creator of the Universe and is the Author of Science. Since God is the Author of the Bible, the Bible is therefore the ultimate authority in any scientific matters. The study of Science is therefore the study of God’s handiwork and is a way of admiring His Creation. God, the Creator, is the One to be worshipped, not the Creation. The Creation, however, reflects the Glory of God and points to His Divine attributes.”

In order to prove that the Bible is the ultimate scientific authority, Dr Leaf attempts to find scientific studies which support Biblical concepts. One example of this is her teaching on Glossolalia, the scientific term for the Biblical concept ‘speaking in tongues’.

Dr Leaf’s Facebook factoid on the neuroscience of speaking in tongues is at least the second time she has posted it. In November when I first saw Dr Leaf’s proclamation on the science of speaking in tongues, I was fascinated. I went to find the research for myself to see if the areas involved in discernment in the brain really increase in activity when speaking in tongues. As it turns out, there isn’t any.

The only study that I could find about brain functioning during speaking in tongues was by Newberg [1]. As I wrote in my previous blog, the study by Newberg showed the part of the brain that’s involved in both speaking in tongues and discernment, the ventromedial prefrontal cortex, decreases in activity when praying in tongues, not increases, in direct contradiction to Dr Leaf’s meme.

In November, I concluded, “there are really only two reasonable explanations as to why the research contradicts Dr Leaf; either there is another piece of research which supports Dr Leaf’s assertion, or Dr Leaf is simply wrong.”

Today on Facebook, Dr Leaf demonstrated that she can not be swayed from her entrenched idea that speaking in tongues increases discernment … or can she? Her meme and her discussion on glossolalia in her ‘Scientific Philosophy’ seem contradictory.

For example, she writes in her scientific philosophy manifesto, “In 2006 Dr. Andrew Newberg at the University of Pennsylvania, using single-photon emission computerized tomography (SPECT), found that the frontal lobe of individuals who spoke in tongues was less active. This brain profile was in contrast to Franciscan nuns in contemplative prayer and Buddhist monks in meditation, in which frontal lobe activity is increased. Since the frontal lobe activity is increased when we are focused on what we are saying, this finding confirms self-reports of what people who spoke in tongues experienced, implying that the words spoken in glossolalia originate from a source other than the mind of the individual speaking in tongues.”

In this paragraph, Dr Leaf confirms that frontal lobe activity decreases when speaking in tongues, in keeping with her anecdotal evidence of “self-reports of what people who spoke in tongues experienced, implying that the words spoken in glossolalia originate from a source other than the mind of the individual speaking in tongues.” But this is in direct contrast with her social media meme, which suggests that speaking in tongues increases frontal lobe activity – the area of the brain common to glossolalia and discernment is the vmPFC, which decreases with glossolalia and increases with discernment.

Dr Leaf is a confusing enigma. She posts social media memes that are clearly wrong, even disagreeing with the scientific papers she has written about and her own conclusions in her own manifesto.

This only discounts her legitimacy. You can’t continue to contradict your own evidence. It’s like shooting yourself in the foot, or digging your own grave. What’s worse, Dr Leaf teaches this from real pulpits, not just on social media. How is her audience supposed to feel when they hear what she has to say and find it disagrees with her own scientific philosophy?

I sound like a broken record, but Dr Leaf desperately needs to review her teaching and social media memes. It’s bad enough to be contradicted by scientific evidence, but to be in disagreement with your own teaching is embarrassing, and does nothing to preserve trust with your audience.

References

[1]        Newberg AB, Wintering NA, Morgan D, Waldman MR. The measurement of regional cerebral blood flow during glossolalia: a preliminary SPECT study. Psychiatry research 2006 Nov 22;148(1):67-71.

Don’t stress about stress – Part 4: Stress breaking bad

This is the last blog post in my brief series on stress. Today, we’re going to look at what happens when we do hit stress overload, and a few simple methods that may be able to help you through a tough situation.

One of my favourite shows of all time was Breaking Bad. Breaking Bad told the story of Walter White, a high school chemistry teacher and average family man, who is diagnosed with terminal lung cancer. To support his wife and disabled son after he’s gone, he uses his knowledge of chemistry to launch himself into an underworld career manufacturing crystal meth.

Allostatic overload is the term modern scientists use for stress breaking bad. Stress moves from an agent of growth and change to an agent of disease and death.

In the last few blogs, we discussed that stress is actually more of a positive than a negative. It’s not that stress can’t be bad, because we know from the stress-productivity curve and from the Yerkes-Dodson Law that too much stress overwhelms our capacity to cope with it. The model used to describe the balance of stress on our body is the theory of Allostasis.

Allostasis

All living things maintain a complex dynamic equilibrium – a balancing act of the many different physiological systems that all rely on the other systems working at an optimal range. Imagine trying to stack ten spinning tops on top of each other while trying to keep them spinning. The body does the chemical equivalent of this very difficult combination of balance and dexterity every day. It’s called homeostasis. This balancing act is constantly challenged by internal or external events, termed stressors. Both the amount of stress and amount of time that the stressor is applied is important. When any stressor exceeds a certain threshold (“too strong, or too long”), the adaptive homeostatic systems of the living thing activate responses that compensate.

The theory of allostasis is related to these homeostatic mechanisms, although not just in terms of stress, but broadly to the concept of any change of the optimal range of these homeostatic balancing processes, in response to a change in the environment or life cycle of an organism [1].

McEwen and Wingfield give an example of some bird species, which change their stress response to facilitate their breeding capacity during mating season. They note that the benefit of the increased chance of breeding is important to the bird, but also comes at a cost of increased susceptibility to some diseases because of the weakening of the stress response at the time [1].

When it comes to stress, we adapt in a similar way. A lack of stress, or an excess of a stressor in some way (either too long or too strong) results in adaptation, which is beneficial, but can come at a cost. This is demonstrated by that broadly applicable U-curve, the stress productivity curve.

Chrousos wrote, “The interaction between homeostasis disturbing stressors and stressor activated adaptive responses of the organism can have three potential outcomes. First, the match may be perfect and the organism returns to its basal homeostasis or eustasis; second, the adaptive response may be inappropriate (for example, inadequate, excessive and/or prolonged) and the organism falls into cacostasis; and, third, the match may be perfect and the organism gains from the experience and a new, improved homeostatic capacity is attained, for which I propose the term ‘hyperstasis’.” [2] And as noted by McEwen, “Every system of the body responds to acute challenge with allostasis leading to adaptation.” [3]

More often than not, we adapt to the stressor, either the same as before, or possibly better. It’s only if the response to the stressor is inadequate, excessive and/or prolonged that stress ends up causing us trouble. This is what people normally think of when they think of stress – called allostatic overload – simply stress breaking bad.

Keeping stress in check

To ensure that we keep our stress levels at the optimum to ensure maximum productivity and growth, here are a few simple techniques. Remember, everyone handles stress differently, and so which of these techniques works best for you will be something you’ll have to learn by trying them.

Breathing

The simplest tool is breathing. Sounds a little silly really, since you obviously breathe all of the time! But we usually take shallow breaths, so our lungs are not being used to their full capacity. When we focus on our breathing and deliberately take slow, deep breaths we increase the amount of air going in, and therefore allow more oxygen to enter the blood stream. This better fuels our cells and helps them do their job more efficiently. However, it also sets in motion a physiological mechanism that slows our heart rate.

Our heart pumps blood from our body, through the lungs to get oxygenated. As we take a deep breath, more blood is sucked up into our chest cavity from our veins, because breathing in causes a temporary vacuum in our chest cavity. The extra blood then fills our heart more efficiently. A more efficient heart beat reduces the need for the body to stimulate the heart to pump harder. This promotes more of the parasympathetic “rest-and-digest” nervous system activity, and less of the sympathetic “fight-or-flight” nervous system, via the vagal brake mechanism.

So, to slow your breathing down simply sit in a comfortable position. Take slow, deep breaths, right to the bottom of your lungs and expanding your chest forward through the central “heart” area. Count to five as you breathe in (five seconds, not one to five as quickly as possible) and then count to five as you breathe out. Keep doing this, slowly, deeply and rhythmically, in and out. Pretty simple! This will help to improve the efficiency of your heart and lungs, and reduce your stress levels.

Remember, B.R.E.A.T.H.E. = Breathe Rhythmically Evenly And Through the Heart Everyday.

Meditation

Meditation takes the techniques of breathing one step further, in that meditation involves deliberately switching your brain’s focus to something simple, and in the present. Focussing on nothing – just breathing and turning off your thinking for while – does take some practice. Concentrating on something in the present (not thinking about the past or the future), tends to be easier and requires less practice, although ignoring all the other thoughts that routinely clamour for your attention might be hard when you first try it.

Focusing on the present moment is part of the practice of Mindfulness. Mindfulness meditation has been studied quite extensively over the last few decades, and has been shown to have benefits over a large number of psychological symptoms and disease states [4].

Sometimes it is easier to focus on something visual, that you can see easily in your field of view, or listen to something constant, like the ocean, or a metronome. The easiest thing to do is to again, focus on your breathing. Concentrate on the sound, rhythm and feeling of your breathing, but don’t engage your thoughts, or allow others to creep in. Meditation quietens the mind, which is excellent for reducing stress, and can help to revitalise and refresh your mind.

Guided Imagery

Guided imagery is a step along from meditation. Instead of focussing on something tangible, guided imagery lets you imagine that you are somewhere pleasant, relaxing, or rejuvenating. Some people describe it as a vivid daydream.

Get comfortable, close your eyes and start to breathe slowly and deeply. Once you begin to relax, imagine your favourite scene. It could be at the beach, or in a log cabin in the snow-capped mountains, or swimming in the cool waters in a tropical rain-forest. Whatever you choose, try to imagine the scene in as much detail as possible, and involve all five of your senses if you can, like, for example, the cool water of the waterfall on your bare skin, the sounds of the birds in the trees, the smell of the moss-covered rocks, the canopy of tall trees and vines split by the waterfall and stream allowing the sunlight to spill in to the forest floor. Enjoy the details and the relaxation that this brings. To “come back”, some recommend counting back from ten or twenty, and to tell yourself that when you reach one, you will feel calm and refreshed.

Guided imagery allows you to actively replace the harassing thoughts of your daily routine with pleasant soothing thoughts. There is some early scientific literature suggesting effectiveness, although more research is required [5, 6]. Again, with practice, this can be done anywhere, and can be done quickly if you need a short break to unwind.

Visualisations

Visualisations build on the techniques of guided imagery, but instead of the rain-forest or tropical paradise, you imagine yourself achieving goals, which again could be anything from improving your health, closing that deal, or hitting that perfect drive from the first tee. Again, try and imagine the scene in as much detail as you can, and involve all of your senses.

PMR

Progressive Muscle Relaxation, or PMR for short, is similar to meditation, except that you contract, hold, and then relax your muscle groups in turn. You concentrate on the feel of the tightening and relaxing of the muscles instead of, or as well as, your breathing. Like meditation, it can be done anywhere and involves very little training.

The contraction of the muscle groups, beginning in your feet – working your way up the calves and thighs, tummy, chest, arms and neck, sequentially pumps all of the blood back towards your heart, giving you a boost of blood flow to your lungs. The deep breathing oxygenates this extra blood and hence, gives your brain a burst of oxygen.

Using PMR to meditate helps engage the vagal brake, and there is some evidence that it helps to reduce persistent pain [7, 8].

Exercise

Exercise releases stress and enhances your physical health [9, 10]. It is flexible and easily adaptable – it is usually free and can often be done without any equipment. The downside is that it is not possible everywhere (you can’t go jogging in a plane), but as a daily discipline, it will enhance your physical and emotional wellbeing.

The benefits of exercise are firstly physical. It gets your heart pumping, the blood flowing and your lungs working to their full capacity. It builds physical fitness, which is important to enable the heart and lungs to work efficiently at all times. Exercise has effects on mood, improving depression [11] and anxiety [12].

It can also act as a form of meditation – the solitude of a run or swimming a few laps, concentrating only on the splash of your strokes or the pounding of your feet on the ground – is similar to meditation except that you’re moving (whereas meditation proper involves being still and relaxed). But the outcome is the same, and stress is often reduced by a session of physical exercise.

Music

Music is almost as fundamental to human existance as breathing, and it’s almost as diverse as mankind itself. Listening to ones favourite music can enhance feelings of control and can increase pain tolerance and improve short term anxiety (stress) [13]. The common characteristics of ‘therapeutic’ music was music which had less tonal (pitch) variation, less prominent chord changes, bass lines, or strong melodies [14].

But the key element was personal preference overall, as some of the participants in the study chose music like Metallica. So enjoy music. Make it part of your day. Even Country and Western may be considered therapeutic!

Yoga

Yoga is an ancient practice that has several components including physical postures (asanas), controlled breathing (pranayama), deep relaxation, and meditation.

It’s not for everyone, but it has clearly defined and scientifically validated benefits to your physical and psychological well-being. “It is hypothesized that yoga combines the effects of physical postures, which have been independently associated with mood changes and meditation which increases the levels of Brain-derived neurotrophic factor (BDNF). Other effects that have been noted include increased vagal tone, increased gamma-amino butyric acid (GABA) levels, increase in serum prolactin, downregulation of the hypothalamic-pituitary-adrenal axis and decrease in serum cortisol, and promotion of frontal electroencephalogram (EEG) alpha wave activity which improves relaxation.” [15] So, translated: Yoga is good for stress relief!

Most gyms and community centres will have yoga instructors, so go ahead and make some enquiries.

Massage

I love massage! The first time I had a proper massage was in the small city of Launceston in the tiny Australian state of Tasmania. After just 30 minutes of the therapist kneading my muscles with her fingers of iron, I felt pretty good, but when I sat up, I was actually light-headed for a little while. My heart rate and blood pressure had reduced so much that it took me a while before I could stand up properly!

Deep pressure massage has also been shown to help release the vagal brake enhancing the activity of the parasympathetic (rest-and-digest) part of the autonomic nervous system. There is good evidence of this effect in pre-term infants [16]. The evidence for adults isn’t so strong, although that’s probably because of a lack of quality research [17]. The good studies that have been done show a reduction of cortisol, blood pressure and heart rate after massage, with some studies showing small persistent effects [17].

The data might be thin, but there is enough evidence to make it worth trying at least once.

Probiotics

I add probiotics to this list as a reference for the future. There is good evidence of the anxiolytic effect of having a friendly bacteria garden in your intestines that interacts with your gut and your immune system in positive ways. But there is, at this point, very little in the way of good quality human clinical trials. And we still don’t know exactly which strains of probiotics are the most helpful for different conditions [18, 19]. But given that they are unlikely to be harmful, it may be worth trailing a course of probiotics, and see how you feel in 30 days.

The bottom line – stress is not the enemy. Sure, if it isn’t handled right, stress can overwhelm us and make us sick, but most of the time, stress makes us productive and strong, and helps us to grow. So, don’t stress about stress.

References

  1. McEwen, B.S. and Wingfield, J.C., What is in a name? Integrating homeostasis, allostasis and stress. Horm Behav, 2010. 57(2): 105-11 doi: 10.1016/j.yhbeh.2009.09.011
  2. Chrousos, G.P., Stress and disorders of the stress system. Nat Rev Endocrinol, 2009. 5(7): 374-81 doi: 10.1038/nrendo.2009.106
  3. McEwen, B.S., Stressed or stressed out: what is the difference? J Psychiatry Neurosci, 2005. 30(5): 315-8 http://www.ncbi.nlm.nih.gov/pubmed/16151535
  4. Keng, S.L., et al., Effects of mindfulness on psychological health: a review of empirical studies. Clin Psychol Rev, 2011. 31(6): 1041-56 doi: 10.1016/j.cpr.2011.04.006
  5. Jallo, N., et al., The biobehavioral effects of relaxation guided imagery on maternal stress. Adv Mind Body Med, 2009. 24(4): 12-22 http://www.ncbi.nlm.nih.gov/pubmed/20671330
  6. Trakhtenberg, E.C., The effects of guided imagery on the immune system: a critical review. Int J Neurosci, 2008. 118(6): 839-55 doi: 10.1080/00207450701792705
  7. Baird, C.L. and Sands, L., A pilot study of the effectiveness of guided imagery with progressive muscle relaxation to reduce chronic pain and mobility difficulties of osteoarthritis. Pain Manag Nurs, 2004. 5(3): 97-104 doi: 10.1016/j.pmn.2004.01.003
  8. Morone, N.E. and Greco, C.M., Mind-body interventions for chronic pain in older adults: a structured review. Pain Med, 2007. 8(4): 359-75 doi: 10.1111/j.1526-4637.2007.00312.x
  9. Fletcher, G.F., et al., Statement on exercise: benefits and recommendations for physical activity programs for all Americans. A statement for health professionals by the Committee on Exercise and Cardiac Rehabilitation of the Council on Clinical Cardiology, American Heart Association. Circulation, 1996. 94(4): 857-62 http://www.ncbi.nlm.nih.gov/pubmed/8772712
  10. Warburton, D.E., et al., Health benefits of physical activity: the evidence. CMAJ, 2006. 174(6): 801-9 doi: 10.1503/cmaj.051351
  11. Rimer, J., et al., Exercise for depression. Cochrane Database Syst Rev, 2012. 7: CD004366 doi: 10.1002/14651858.CD004366.pub5
  12. DeBoer, L.B., et al., Exploring exercise as an avenue for the treatment of anxiety disorders. Expert Rev Neurother, 2012. 12(8): 1011-22 doi: 10.1586/ern.12.73
  13. MacDonald, R.A., Music, health, and well-being: a review. Int J Qual Stud Health Well-being, 2013. 8: 20635 doi: 10.3402/qhw.v8i0.20635
  14. Knox, D., et al., Acoustic analysis and mood classification of pain-relieving music. J Acoust Soc Am, 2011. 130(3): 1673-82 doi: 10.1121/1.3621029
  15. Balasubramaniam, M., et al., Yoga on our minds: a systematic review of yoga for neuropsychiatric disorders. Front Psychiatry, 2012. 3: 117 doi: 10.3389/fpsyt.2012.00117
  16. Field, T., et al., Preterm infant massage therapy research: a review. Infant Behav Dev, 2010. 33(2): 115-24 doi: 10.1016/j.infbeh.2009.12.004
  17. Moraska, A., et al., Physiological adjustments to stress measures following massage therapy: a review of the literature. Evid Based Complement Alternat Med, 2010. 7(4): 409-18 doi: 10.1093/ecam/nen029
  18. Bested, A.C., et al., Intestinal microbiota, probiotics and mental health: from Metchnikoff to modern advances: Part II – contemporary contextual research. Gut Pathog, 2013. 5(1): 3 doi: 10.1186/1757-4749-5-3
  19. Bested, A.C., et al., Intestinal microbiota, probiotics and mental health: from Metchnikoff to modern advances: part III – convergence toward clinical trials. Gut Pathog, 2013. 5(1): 4 doi: 10.1186/1757-4749-5-4