science of yoga

Does meditation change the brain? Or do an individual brain's qualities make some people more attracted to meditation than others?

You might expect someone who meditates regularly to show up as calm and thoughtful. Yes, research shows that meditation practitioners tend to have low impulsivity. But what comes first? Does meditation make someone less impulsive? Or do naturally calm people choose to spend time meditating?

Impulsivity is a personal trait, a tendency to act on a sudden urge. Extreme impulsivity is linked to psychological disorders (ADHD, personality disorders, and even brain injuries). Studies show that impulsive behavior correlates with brain structures responsible for planning and motor control.

A 2019 study compared these brain structures in long-term meditators (people with thousands of hours of lifetime meditation practice) with people who have never meditated. Researchers found differences in the neural measures of impulsivity between the groups. However,  the brain measures were not dependent on the extent of meditation practice. Instead, differences between meditators and non-meditators may be pre-existing. People with a particular neurological make-up may be more attracted to extensive meditation practice than others. 

Another study from 2013 showed that people engaging in compassion meditation might have a neurological predisposition in the way they respond to suffering. The study participants received painful electrical stimulation, and watched others receiving same stimulation. Neuroscientists put people through this unpleasant process to measure their empathy and brain responses. Participants then took up compassion and mindfulness meditation training. The brain activity in response to pain predicted how much time they would spend practicing mindfulness and compassion.

Does meditation change the brain and personality? Or do baseline differences in impulsivity, compassion, and other characteristics make some people more attracted to meditation?

I think that, likely, both are true.  

Anything that we do over and over again shapes our brain.  At the same time, our brain determines if we stick to the practice.

We occasionally hear instructions from yoga teachers that set our alarm bells ringing. Some of these instructions are misguided but relatively harmless, but others can have downright detrimental effects.

Check out the facts behind the top 5 misleading instructions below — and next time you hear instructions like these, pause and allow yourself some critical thought. Whether teacher or student, we can all reflect carefully on what information we absorb and repeat.

Instruction 1. Stimulate thyroid in halasana

The thyroid is a small endocrine gland in the neck. There is a belief that flexing the neck in halasana or similar asanas stimulates the thyroid. However, there is no convincing scientific evidence for this idea. No scientific study has compared the endocrine effects of halasana to that of other asanas.

INSTRUCTION 2. TWIST TO DETOX

A perfect example of a commercial myth is ‘detoxifying ’! Toxins don’t build up in the body. Our liver and kidneys are continuously busy excreting metabolic products. If the kidneys or liver fail to do their job, a severe organ dysfunction requiring medical aid develops rather quickly. If the kidneys and liver are functioning well, there is no need to eliminate toxins with special drinks, massages, or yoga asanas.

INSTRUCTION 3. Use Alternate Nostril Breathing to balance the left and right brain hemispheres

There is no direct passage from the left/right nostrils to the left/right brain hemispheres. When you breathe in through your nose, the air enters the trachea and then goes via the bronchi to the lungs. There, the oxygen gets absorbed into the blood and travels to the brain. It does not matter if you have inhaled with the right, left or both nostrils — the blood flow brings oxygen to both brain hemispheres.

INSTRUCTION 4. Do inversions to increase blood flow to the brain

The brain is protected from an influx of blood that may damage its delicate capillaries and cause a stroke. Despite what you may have heard at a yoga class, the brain cells are not "bathing in fresh blood" when we are upside down. Besides, inversions tend to slow down the heart and lower blood pressure, which means that the amount of blood going into the brain may even reduce in inversions (check out this research proof!).

INSTRUCTION 5. Watch your thoughts — 85% of them are negative

It is common for people to have repetitive thoughts. We worry about the future or replay past events. In some conditions such as depression and anxiety, worry and rumination become excessive and may increase distress and suffering. But repetitive thinking can also be constructive: it brings healing from emotional wounds of the past and enables us to solve problems and plan the future. The statement "85% of our thoughts are negative" appeals to those of us who love exact numbers, along with similar statements such as: "people only use 10% of the brain", and "people have 70,000 thoughts per day".

What yoga instructions do YOU find misleading?

We would love to hear your thoughts. Leave your comment below!

In their recent article in Frontiers in Psychology, Dr. Shirley Telles and her colleagues explore the reasons that lead to injuries or illness due to yoga practice. Dr. Shirley Telles is the director of the Patanjali Research Foundation in Haridwar, India, and an editor of “The Principles and Practice of Yoga and Healthcare”.

The most common reasons for adverse events, according to Dr. Telles, are (a) practicing yoga for an unusually long duration, (b) practicing yoga more frequently than is recommended, (c) excess strain on a specific joint during yoga practice and (d) ignoring a prior health condition which could be a contraindication for a specific asana/exercise.  

How can we improve safety and reduce adverse events related to yoga practice as therapy?

safety Guidelines for Yoga practitioner 

Motivation: you are motivated to learn safe yoga.

Objectives: you are clear about the objectives to practice yoga, for example to manage symptoms of a chronic illness, to improve your stress response, or to balance your lifestyle.  

Supervision: your yoga practice is under the supervision of a reliable and trained yoga instructor.

Boundaries: you view yoga instructors with respect, but are not confused by concepts of a “guru” or the “need to surrender” which could lead to weakness, a dissolution of boundaries and hence exploitation 

Disclosure: you are open about any earlier accident/injury or surgery to the yoga instructor. This is especially important if you have a diagnosed health condition.

Attitude: you approach yoga for self-improvement without a sense of competitiveness which could lead to going beyond your physical ability and hence resulting in injury.

Expectations: you have realistic expectations and not expect miraculous changes/cures.

Pace: you approach the practice at your own pace and do not force through it. For example if you miss a yoga session on one day increasing the practice the next day may not be appropriate.

Monitoring:  if you notice any changes in your general health or specific symptoms, or there are changes to your current medication, you report it to your yoga instructor/ yoga therapist.

"[In reports of] adverse effects associated with yoga practice, the subjects were either (i) practicing the yoga technique incorrectly, (ii) having precondition(s) related to the reported adverse effect, or (iii) were not aware that the particular yoga technique they were performing could worsen the precondition that they had." Full article text

safety guidelines for Yoga instructor or yoga therapist

Motivation: you are motivated to teach safe yoga.

Training:

• you are experienced in yoga practice and theory based on knowledge of traditional yoga texts and the commentaries written on them. 
• you have basic knowledge of physiology, functional anatomy and biomechanics. 
• as a yoga therapist, you know therapeutic yoga in theory and practice and additional information about basic diagnostic methods and the disorders they may treat.
• you know the basics of first aid (for example how to treat minor injuries, record the pulse, blood pressure and body temperature). Ideally you know on-the-spot emergency treatments (e.g., cardiopulmonary resuscitation, managing choking, bleeding and fractures) as well as the contact details of a hospital nearby.

Context: you gather information about any earlier accident/injury or surgery of your students. As a yoga therapist you have detailed case histories and knowledge of your patients.

Caution: you are aware about the contraindications of yoga practices. As a yoga therapist, you are cautious attempting to treat patients who are weak, liable to fall, have poor balance or are otherwise “high risk cases.”

Clarity: you communicate with complete clarity about the method of practice and the contraindications of the practice.

Reporting: you are able to report an adverse event with sufficient accuracy to a medical practitioner if necessary.

"Most of the studies which were conducted to assess the efficacy of yoga practice did not identify or report adverse events in the trials. This may be due to the fact that in such studies the yoga interventions were designed and delivered under the supervision of experienced yoga teachers. [...] It could also be that adverse events were not reported or noted by the yoga teachers as they were not trained to do so." Full article text

One afternoon I received a phone call from my friend, broken by anxiety. Her son went to an emergency surgery after a spine injury. She called me from a waiting room in the hospital as the surgery started. How could I help her from a thousand kilometers away? The only thing I could do was to stay with her on the phone and tell her to breathe slowly. The surgery went fine.

“By Exhaling And Restraining The Breath Also (The Mind Is Calmed).”  Patanjali Yoga Sutra, Chapter 1, Sutra 34

Ever since I use this as an all-purpose advice: breathe! Slow breathing helps to decrease anxiety, and increase feelings of relaxation, ease and comfort. How does this work?

4 MECHANISMS BY WHICH SLOW BREATHING CHANGES EMOTIONS

1) Vagus nerve: The heartbeat speeds up when we inhale and slows down when we exhale. Imagine what happens when you practice slow breathing for a few minutes: the heart slows down, then speeds up on every breath cycle. This oscillation of heart rate depends on the parasympathetic system: the vagus nerve. Slow breathing increases the vagus activity. Information from the vagus transmitted to the brain  brings you to the state of relaxation, safety and calm.

2) Cerebral blood flow: A recent article in Current Opinion in Behavioral Science suggests that oscillations in the heart rate during slow breathing results in oscillations in the flow of blood to the brain. Brain regions associated with emotion regulation are among those that are mostly affected by the changes of blood flow. The rhythmic alterations of blood flow affect how these brain regions talk to each other. This results in a change to your emotional state.

“Positive feelings such as love, compassion, kindness and wonder often come with deep, comfortable and energizing breathing and open, affirming and enthusiastic feeling throughout the body." - Dough Keller, Refining the Breath

HOW TO SLOW DOWN THE BREATH

Modern studies, as well as ancient texts, recommend slow breathing at a pace of ten breaths per minute or less. Six breaths per minute is a rhythm that is often used in pranayama guidelines and research studies. This roughly means 10 seconds per one breath cycle. 

Practice Now!

Counting:  Sit in a comfortable position and inhale through your nose while counting slowly up to four. Feel how your lower ribs expand on the inhalation. Without pausing to hold the breath, exhale slowly through your nose while counting at the same speed. Engage your belly muscles gently with your exhalation.  Gradually increase the time of the inhalation and exhalation until you find a comfortable rhythm. You may use uneven counts, but in that case, see if you can make your exhalations a little longer than the inhalations. 

Paced breathing: Sometimes it might be easier to rely on an external rhythm, rather than do the counting. There are hundreds of mobile apps and youtube videos, offering sounds for paced breathing.  Find what works for you!

Heart-rate variability biofeedback: You could bring your slow breathing practice to a whole new high-tech level by using a biofeedback device. It measures your heart rate and transforms the data into a game for you to play on a computer or a phone. The goal of the game is to slow down the breath to maximize the heart-rate variability.

Whether you count to yourself, use an app or a device, you can practice slow breathing anywhere, anytime. Do it while standing or sitting, in the office or on the train. Regular slow breathing improves cardiovascular health and emotional wellbeing. And it can really help in emergency situations.

The number of bacteria cells in our guts exceeds the number of cells in our body. For the bacteria, our guts must feel like a planet. Same as humans shape global processes on Earth, bacteria change their environment — us. 

INTRODUCING BACTERIA: We are not under our own control

It turns out that bacteria can communicate to the brain directly by hijacking vagus nerve signaling. An  article published in Neuron yesterday explains how it works. The vagus nerve delivers information from the guts to the brain, and back. Its sensory branches end in the epithelium (the inside layer) of the intestines. The microbiota can alter vagus signaling by changing the concentration of nutrients, peptides, and hormones inside the guts. Within seconds, information about these chemical changes is transmitted to the brain. 

Why is this important? We know that information from the vagus affects our emotions, decisions, and even memory processes. Vagus nerve activity may also influence our social connection and bonding (read here).

Bacteria make physical changes to the brain and who we are

Experiments in mice demonstrate that certain gut bacteria species alter social behavior. By activating the vagus nerve, the bacteria increased oxytocin levels in the brain and made the mice more social. To make the story even more mind-blowing,  studies show that gut microbiota influence gene expression in the cortex and may change the brain structure and function. 

Studies on humans have shown that changes in microbiota affect psychological processes and may contribute to psychiatric disorders. This includes mood and anxiety disorders, autism and schizophrenia, and even neurodegenerative disorders such as Alzheimer’s and Parkinson’s diseases.

While science is only starting to understand the complexity of mind-body-microbiota relationships, it seems like the vagus nerve plays an important role. Prof. Stephen Porges, a pioneer of the research of vagus and mind-body connections, and Prof. Sue Carter, an oxytocin expert, will come to Amsterdam in May this year for our conference “The Science of Human Connection in Yoga Therapy”. They will be ready to answer all of our questions about the vagus nerve.

WE KEEP BACTERIAS HAPPY AND THEY KEEP US HEALTHY

The vagus nerve communicates information from, but also to the gut. We know that exercise and slow breathing practices may increase vagus activity and influence the composition of microbiota. Together with a healthy diet and stress management, exercise or yoga helps to keep our microbiota balanced. And it seems like balanced microbiota in turn keeps our moods and behaviour balanced. 

So:

Namaste. The bacteria in my gut send light to the bacteria in your gut.  

Just a couple of weeks ago Anneke and I were in London at the Yoga in Healthcare Conference. What a fantastic feeling to be in a room full of like-minded colleagues, and learn about inspiring developments in the integration of yoga with modern medical science.

For example, the Yoga in Healthcare Alliance recently launched a 10-week yoga program in London, in collaboration with the National Health Service. Participation is free and open for all patients registered at a general practitioner (that is, everyone!). The program empowers people to use yogic tools: breathing practices, simple asanas, meditation and mindfulness, relaxation techniques.

Yoga as a Lifestyle therapy

In a world where most diseases come from poor lifestyle choices, yoga can be seen as a “lifestyle therapy” to improve health and wellbeing and prevent long-term chronic conditions.

New evidence for the significant positive effects of yoga comes out nearly every day.

A new meta-analysis of yoga trials published between 1983 and 2018 concludes that yoga significantly reduces blood pressure. Particularly in people with hypertension, yoga can bring blood pressure back into the normal range. The effect is strongest when yoga is practiced at least three times a week, and the practice should incorporate not just asanas, but breathing exercise and meditation.

As we learn more about the powerful effects of yoga as a lifestyle therapy, how can we further promote its integration in healthcare?

For me it means sharing this knowledge with doctors and healthcare experts, setting up accessible yoga classes and challenging the mainstream image of yoga that focuses on flexibility and body shape.

What other ideas do you have?

Irina

changes in choices and actions

How does your life change if you start practicing love, kindness, and compassion? Research shows that people who practiced loving-kindness meditation in an extensive 3-month training made more altruistic choices at the end of the training. They were more likely to help others, compared to people who practiced breathing or observing-thoughts over the same period of time.

Changes in the brain

As part of the same research project, scientists investigated the brain changes in long-term meditation practitioners from the Nyingma Buddhism tradition. This tradition emphasizes loving-kindness and compassion. Seventeen meditators with over 20 years of daily loving-kindness meditation experience were compared to 15 control participants with matched age and education, who had never practiced meditation before.

All participants had to do a simple task in an MRI scanner: first, just do nothing for 7 minutes, and then, practice a 7-minute loving-kindness meditation with these beautiful instructions:

Brain plasticity

The researchers found signs of learning-induced brain plasticity in the meditators compared to the controls. Meditators showed structural changes (increased cortical thickness) in brain regions that support attention, empathy, and communication. These brain regions were also more active in meditators than in controls during the MRI meditation task.

This study is one of the first to show that the regular practice of evoking emotions leads to plastic changes in the brain.

Thank you for reading!

Please share your thoughts and comments below.

Irina