Ways in which our brain influences our awareness

"Ouch, that hurt!"

Let's take a moment to look at this simple expression.

As journalist Oliver Burkeman said in this lovely article in the Guardian recently, (slightly paraphrased) "when you stub your toe on the dining table, your nerve fibres shoot a message to your spinal cord, in turn sending neurotransmitters to the thalamus, which activates (among other things) your stress response. Ok, but what about the agonising flash of pain? And what is pain, anyway?" To that I would add the question "what about the times we stub our toe and don't even realise...?" What's happening?

Let's first look at the neuroscience. 

As Burkeman says, when we stub our toe these pain signals (like any other sensation like heat or pressure) travel from the peripheral nerves to the spinal cord and up into the brain. Modern neuroscience tells us the spinal cord contains special nerve fibre bundles that serve as "gateways" to the brain, controlling whether or not a signal gets passed on or not. These gateways have the ability to mute or amplify sensations depending on the relative mix of physiological and, importantly, psychological stimulus input. So what does this mean?

Opening and closing the gates

There's a nice example given here in the book "Relaxation, Meditation, & Mindfulness: A Mental Health Practitioner's Guide" by Jonathan Smith. Let's first imagine you're at home playing with your young niece and she suddenly grabs your hand tightly, squeezing your fingers and your knuckles together. Ouch! You feel a sharp sensation of pain. These are your peripheral nerves sending the signals to your brain.

Now imagine as she grabs your fingers and squeezes, she giggles and plants a wonderful smiling kiss on your cheek! This time you barely notice her squeezing your fingers – this is because the pleasant distraction (initially) closes the nerve gateways as you attention is redirected. The feedback from subsequent thoughts and feelings, such as "she's such a wonderful kid!”, continue to hold the gates closed.

Then she lets go of your hand and you see that your fingers have gone white! But by now your brain has realised that the squeeze was completely innocent and you're not injured. What might otherwise be experienced as pain may instead be experienced as a strong tingling sensation.

Now imagine you're sitting on your sofa with your arm are dangling over the side out of sight. Suddenly you feel something tighten around your fingers and knuckles. Not knowing what it is you feel a stab of pain. Then come the associated thoughts: "it's the dog!", and the pain grows stronger. You feel a shot of fear over possible damage to the skin or infection, and it gets even stronger. This time the pain sensations, and the feedback from subsequent thoughts and feelings, blow open the pain gates and you're all too consciously aware of it all. Perceived threats are very powerful activators of the brain's systems.

Thankfully the example given in the book gives a positive ending to this scenario: you turn to look for the offending dog and discover it is just your niece again. The gates start to close, the pain goes away, hastened by a burst of laughter triggering a release of endorphins and a further closure of the gates!

So there's an interplay between the different types and levels of stimulus inputs, including from our nerves and sense organs, emotions, endorphins, and thoughts, and it's all affected by how our attention is directed. This interplay controls the state of the gateways, and therefore our experience of pain. This is known as "gate-control theory" after Ronald Melzack and Patrick Wall who came up with it in the 1960s (Melzack & Wall, 1965, 1982).

The reticular activating system

In the journey up to the brain, the next area the our sensations have to pass through is the brain stem. This area is responsible for (1) regulating most of the body's automatic functions (breathing, heartbeat, blood pressure, etc), and (2) relaying information to and from the brain to the rest of the body. It plays an important role in consciousness, awareness and movement (and it is only when brain stem function is permanently lost that a person is confirmed as dead.)

An important area in the brain stem for us in the mindfulness business is the reticular activating system (RAS) since it can have a strong influence on what we actually become aware of. 

Sorry, the reticular what...?!

The reticular activating system, or RAS (but not RAS) is also thought to play a role in many important autonomic functions, including regulating sleep and wake, arousal and breathing. However, perhaps its most important function is its ability to focus our attention on something. It is the portal through which nearly all sensory information enters the brain, and it acts as an initial filter to all this incoming information to stop us getting overloaded. It dampens down repeated or excessive stimuli, and flags up any crucial information that threatens survival or is just new and different. It's part of our internal editor.

Imagine walking down a busy shopping street with a blister on your foot. You've been walking all day, and with your attention on navigating the crowds and getting to the next shop you filter out the soreness on your foot – thanks to your RAS. Then someone in the crowd treads on your foot and boom, suddenly you notice! That again is your RAS working for you.

The sense gates in the spinal cord and the RAS in the brain stem are therefore similar in function. The RAS operates at a slightly higher level though, filtering and editing higher level sensations and thoughts.

So what is pain?

I think the above examples illustrate a few different aspects of pain. There are the nerve impulses that are relayed up the spinal cord to the pain gateways. Depending on our physical and emotional state, these gates open letting the pain sensation through, or don't, blocking or modifying the signal. Then there's our reticular activating system which acts at a higher level to dampen down repeated or excessive stimuli, or flag up any life-threatening (or just new and exciting) information.

Assuming that the pain signals pass through all the way to our awareness, then we perceive pain. Then come all the layers of associated thoughts and emotions: "I'm so stupid, why did I burn myself again?", "Why won't this pain go away?", "I hate this pain!", "I must have done something bad to deserve this", etc.

Someone wise once said "pain is inevitable, suffering is optional". A considerable proportion of what we perceive as pain arises through our anxious desire to suppress it, and that's where our mindfulness practice can really work in our favour. The Buddha said, “When we’re touched with a feeling of pain, we feel sorrow, grief, and, beating our breast, become distraught. We feel two pains, physical & mental. Just as if we were to shoot a man with an arrow and, right afterward, were to shoot him with another one”. The physical pain may be unavoidable, adding the mental pain is our choice.

Influenced awareness

So our unconscious systems can modify our sensory inputs before we're even conscious of them. A recent article I read (p26) paraphrased this as "the eyes only see and the ears only hear what the brain tells them" – in short we all pick opinions then find data to support these beliefs and this becomes our reality. Since our mindfulness practice is all about increasing awareness and knowledge of ourselves and how we interpret reality, it's important to know about all these unconscious influences so we can recognise them when we feel their effects.

I am a member of the Zenways sangha led by Zen master Daizan Roshi, and I teach meditation, mindfulness and yoga at the ZenYoga studio in Camberwell, London. See my website for further details.

I'd love to hear from you

Perceptions on your pain gateways? Reflections on the reticular activation system? Leave a comment below, join the discussion.

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Sacrum - the holy bone

Credit: http://prenatalyogacenter.com

Your sacrum is the large, triangular bone at the base of your spine. It consists of usually five initially separate vertebrae which begin to fuse at about age 16–18, and are usually completely fused by your mid-30s. The sacrum sits like a wedge between your two hip bones (ilium), forming the sacroiliac joint (SI-joint). Below the sacrum is your tail (coccyx).

The whole sacro-iliac area is incredibly interesting when it comes to movement, yoga, and our energetic system. But have you ever thought why the sacrum is called that? I certainly hadn't until I heard someone the other day refer to it as our sacred bone. Wow, of course! – sacrum, sacred. Is this a true connection, or just a coincidence? Why would the sacrum be sacred??

A very brief Wikipedia search shows that the name "sacrum" originates from the Latin os sacrum, a translation of the Greek hieron (osteon), meaning sacred or strong bone. So it does come from the word sacred...

In this paper researching this history of the term (yes there's even a paper on the subject!), Oscar Sugar found that in European/Middle-Eastern tradition the sacrum is associated with resurrection, identifying it as the "almond" or luz of the Hebrews and the ajb of the Arabs. The idea goes that the sacrum is the last bone in the body to disintegrate after death (it's one of the hardest bones in the body) and is therefore necessary for resurrection – it seems there are a few mentions of this in the Bible, for example in Psalms 34, 21 it says "He watches over all the bones; one of them shall not be broken". He concludes that the word ultimately derives its conceptual meaning from the ancient Egyptians who associated it with Osiris, the god of the afterlife, the underworld, and the dead.

Interestingly, according to this paper, some Mesoamerican Indian languages also named this bone using words referring to sacredness and deity, meaning that they must have independently come up with this concept. So it's not just the Europeans!

Another reason given in a few studies why it's called 'sacred' is that it's located next to the reproductive organs, which are obviously historically, culturally and symbolically highly significant! It looks like their proximity has led to people thinking that they share similar life-giving or spiritual qualities. Several cultures around the world (including the ancient Egyptians and some Indian cultures) have even believed that the sacrum channels seminal fluid through the spinal column to the penis (apparently because spinal fluid and semen are very similar in form). The great Leonardo da Vinci looks like he might've made a similar wrong assumption when he drew a seminal duct leading from the sacrum at the bottom of the spinal cord to the penis in his drawing of a man (I can't find the actual drawing on the internet though).

On a purely physical level, the sacrum bone forms the centre of support for the human bodily structure, and as such is well designed to take great physical stress. Unfortunately, if we put too much stress on it or move badly this area can be the source of much lower back pain. One of the things we work on in our yoga practice is the opening and stabilising the hips, sacrum and the SI-joint so that we can sit comfortably. This stability allows us to sit still for long periods of time, as we do in meditation.

In Indian spiritual practices, the area around the sacrum is seen as the seat of Kundalini. The word kundalini comes from the Sanskrit word 'kundal' meaning coiled up. It is seen as the primordial dormant energy present at the base of the spine in the sacrum – often visualised as a coiled snake. According to the texts, Kundalini is associated with the Divine Mother (Shakti, or the earth). One of the primary goals of traditional yoga practice is the uncoiling (release) of this feminine energy at the base of the spine, which can then travel up the central energy channel (susumna) to unite with the masculine energy of Divine Father (Shiva/Shakta, or the universe) in the seventh (crown) Chakra. This union of opposites is the essential meaning of yoga (to unite or yoke, bring together), and is a powerful symbol in pretty much all cultures.

"The word Kundalini is derived from a Sanskrit word 'Kundal' meaning coiled up. It is the primordial dormant energy present in three-and-a-half, coils at the base of the spine in a triangular bone called the Sacrum - See more at: http://www.adishakti.org/subtle_system/kundalini.htm#sthash.XV2FJOBC.dpuf"The word Kundalini is derived from a Sanskrit word 'Kundal' meaning coiled up. It is the primordial dormant energy present in three-and-a-half, coils at the base of the spine in a triangular bone called the Sacrum

"The word Kundalini is derived from a Sanskrit word 'Kundal' meaning coiled up. It is the primordial dormant energy present in three-and-a-half, coils at the base of the spine in a triangular bone called the Sacrum - See more at: http://www.adishakti.org/subtle_system/kundalini.htm#sthash.XV2FJOBC.dpufjjjjjjjjjjjj

In East Asian practices, the sacral area is associated with the lower Tan Tien (or Dan Tian; Chinese, Tanden; Japanese) literally translated as "field of elixir", and your 'hara'. They use the word 'elixir' to refer to the same kundalini energy. In practices such as Qigong, Taoist yoga, and Zen, instead of awakening that energy and just allowing it to rise up the spine, they practice balancing both the rising and descending energies (yin and yang) by learning how to move it up the back and down the front of the body in a complete circle (the snake swallows its tail). This is known as the microcosmic orbit.

So there we have it. In all our modern scientific medicalisation of our bodies we have, in our name for the sacrum, a persisting shadow of our past beliefs and spiritual practices. Our sacred bone: made of 5 fused vertebrae, the physical centre of support for our body and often the source of lower back pain when we move/lift/strain badly, necessary for resurrection, and the seat of our feminine kundalini or elixir energy.

I teach Zen yoga and mindfulness at the ZenYoga studio in Camberwell, London. See my website for my class schedule and more details.

I'd love to hear from you

Got another take on the sacrum bone and why it's called that? I'd love to hear from you! Leave a comment below, join the discussion. 

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What is your fifth limb?

The classical yoga of Patañjali comprises of eight so-called "limbs" (stages/practices). Ashtanga, by the way, means eight limbs (ashta=eight, anga=limb). In his system the fifth limb is Pratyahara, often translated as 'withdrawal of the senses'. But that's not the 5th limb I want to talk about here.

I want to talk about your fifth anatomical limb - your spine. My teacher Jonathan Monks defines Hatha Yoga as the liberation of the fifth limb. But what does liberation mean, and why would you want to do that to your spine?? Liberation means the act of setting free, or being free from limits. Do you see your spine being limited? About 8 in 10 people in the western world have one or more bouts of lower back pain in their lives. It's also the most common reason for absence from work and having to go to the doctor. So developing increased flexibility, strength, and awareness in the spine is absolutely crucial for living a healthy life - especially as you get older.

Your spine is the major trunk road connecting everything in your physical body (and energetic and spiritual body, but let's not get too technical). Your legs extend downwards from it forming, together with your pelvic floor, your roots. The very important psoas muscle connects the inside of your thighs to your spine, and its flexibility combined with that of your sacroiliac joint (SI joint) and your lower few vertebrae affect how your hips and pelvis move, your gait, and your posture. The SI joint is in fact a firm favourite for discussion in the yoga literature (see this excellent article) as it can end up hurting as a result of incorrect yoga practice. In the Japanese tradition, your hara - your central engine or energy battery - sits in front of the spine, in your belly.

Your shoulders also hang off your spine. Maybe you often feel tension up here too. One of the main causes of those painful muscle knots often stem from our sedentary lifestyle containing short bursts of activity or sustained holding from a hunched or forward-head posture.

So you can see why liberating the spine is so important. In the YogaMonks practice that I've been studying this last few years, it's an absolute focus. The practice Jonathan sets for us (mere beginners) is all about opening our root - bringing physical freedom of movement to the lower spine and pelvis, awareness to our perineum (pelvic floor), softness to the belly (and hara), and an increased (energetic) connection to the ground.

And as our spines start to move more and more independently of our other limbs, many wonderful things start to happen! As this lovely article puts it, our "hips are the body's junk drawer - they hold emotional stressors when you’re not sure where else to put them, yet you're not entirely ready to release them." So increased flexibility in the hips and pelvis can have a serious effect on our emotional body, releasing stuff that might've been stored there for years.

A loose and relaxed upper spine allows your breathing to become free and easy. Eventually (so Jonathan says) pranayama starts to happen spontaneously. Pranayama is the conscious direction or movement of energy around the body, usually through the breath.

Ultimately, a liberated spine will allow you to sit comfortably in padmasana (full lotus), the body stable, solid and connected to the ground, and the mind quiet, alert, and inquisitive. And that's all we want - the rest of it just happens in it's own time.

I am a member of the Zenways sangha led by Zen master Daizan Roshi, and I teach meditation, mindfulness and yoga at the ZenYoga studio in Camberwell, London. See my website for further details.

I'd love to hear from you

What's your relationship to your 5th limb? What have you found that helps develop this relationship? Leave a comment below, join the discussion.

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