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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The rational mind should really be just an advisor to the king

After writing my article a couple of weeks ago on intention and gut feeling, I've been thinking some more about how our rational, thinking mind interacts with our emotional, feeling mind. Do you ever catch yourself in a situation where it seems these two sides seem at odds with each other? I do.

Let's say it's raining and I'm trying to decide whether to cycle into town or take the bus. Rationally it would make sense to cycle – it's free, much quicker, and the exercise is good for me. However, I'm a bit tired and I know it's raining and cold, so the bus makes for a very attractive option!

It's very easy to fall into the trap of seeing this as a battle. Do I side with my feelings or my calculations? Which option is best?

My Zen teacher, Daizan Roshi, likes to say the rational mind is like an advisor to the king. If we're not careful, this advisor can easily have delusions of grandeur and assume the role of leader. And I think this position is encouraged somewhat by our society.

In nursery and primary school our education focusses on our whole bodies – we dance, do drama, and paint with our hands and feet. By secondary school, we're only being educated from the waist up (with occasional classes of PE), and by university we're focussed solely on head-learning. We train the mind to gather and process information – facts, figures, critical thinking, logic, reason – and we test these abilities (and these alone) via incessant exams. The people best at this are ones admired and rewarded most highly in our society: scientists, lawyers, doctors (because western medicine is essentially all reductionist), bankers, computer programmers, etc. On the whole our Western society is skewed towards the rational over the emotional. Einstein knew this when he said

“The intuitive mind is a sacred gift and the rational mind is a faithful servant. We have created a society that honours the servant and has forgotten the gift.”
― Albert Einstein 

The problem is the rational mind is not a good leader. It's too cold and calculating. But it is an excellent advisor. When we let the intuition, the true king/leader, assume its rightful place then logic and reason becomes only one source of information among many. By the same account, emotions and feelings are also just another source of information. In the end I decided to take the bus not cycle!

To take another example, back when I was deciding whether or not to quit my job as an astronomer, my rational mind was screaming "Why quit? You're well-paid, an expert at what you do, and have put in years of training." But it could also calculate how difficult it would be to get a job in the UK and what impact that would have on my relationship. This was all excellent advice. I also knew I wasn't enjoying the day-to-day aspects of my job, feeling quite isolated and frustrated with my colleagues, and I wanted to work more with people in an everyday, grounded sense. All of these things informed my eventual decision, which I feel almost bubbled up out of the muddy quagmire of swirling thoughts and opinions.

I guess you would call that my intuition...

I am part of the Zenways sangha led by Zen master Daizan Skinner, and we meet twice a week at our dojo in Camberwell, London. For more info see www.zenways.org

 

I'd love to hear from you

Any comments or thoughts about your king and advisors, I'd love to hear from you. Leave a comment below, join the discussion. 

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Meditation is not about clearing your mind!

One of the most common misconceptions about meditation is that it’s all about clearing your mind. And sadly this idea seems pretty pervasive. Most people I talk to who've never done much meditation before say something like "oh I can't do meditation, I can't clear my mind".

I'm not surprised! Clearing the mind is nigh-on impossible! Even for someone like a Zen master with decades of meditation experience. But perversely it's often this clear, calm, unaffected mind-state that brings people to meditation in the first place. We all want to find some respite from the whirlwind of thoughts and worries in our heads.

Then when you try it and find your mind is anything but clear, it can be very frustrating!

I think one very useful way of thinking about the brain is like any other organ. The function of the heart is to pump blood; the function of the stomach and intestines is to secrete enzymes and digest food; the thyroid to secrete hormones; and likewise, the function of the brain is to secrete thoughts. Thoughts are a natural product of the brain. Why would we want to stop them?

It's not the thoughts themselves that are the problem, it's how we engage with them. So often we unconsciously end up following trains of thought, and, more often than not, these end up going down a negative route, leading us into worries and anxieties.

Mindfulness is all about developing our awareness of how things are in this moment, without trying to change it, or judging it to be good or bad. So when we come to practising our mindfulness meditation, our first job is to notice just how busy the mind is. Some days it might be as busy as the M25 at rush-hour, and other days like a quiet country road... Either way, that's fine. One of the most wonderful effects of observing the mind as it is right now without trying to manipulate it in any way is that it automatically begins to calm down. The less we try, the more it responds.

One helpful analogy to how our mind and thoughts work is the following. Imagine yourself walking deep in the countryside and you come to a river. You take a rest and come to sit on the river bank. In this analogy your thoughts are like the water in the river, flowing naturally downstream. Let's say you find a few large logs and attempt to dam up the river – you try to "clear your mind". Firstly, this takes a great deal of effort. You might succeed in creating a dam, but sitting back to admire your work you see that the water level is gradually rising behind the dam. At some point it either flows over or around the dam, or the dam breaks...  It's much easier just to let the water flow.

The other trap we get into is jumping into the river and grabbing hold of the various thought forms that flow down this river. Let’s say you see something awful on the news. Immediately your mind is flooded by a whole range of negative thoughts and emotions like anger, sadness, fear, revenge. Before you know it, your mind is grabbing similar thoughts from its memory banks, and new thoughts come in followed by more emotions. The next thing you know, you're totally consumed by these thoughts, wondering about the safety of those you saw on the news, of you, your family, friends, what to do about it, how to stay safe, etc.

So instead of engaging with these thoughts as they arise, in our mindfulness meditation we practise simply observing the thoughts – sitting by the riverside, seeing the flow of thoughts for what they are. Not trying to block them, but also not grabbing hold of them. We practise making the choice not to engage with the thoughts as they arise, so we have that choice in every part of our life. Sometimes it's imperative that we do engage with our thoughts, but sometimes it's more healthy not to.

I teach 8-week courses in Mindfulness for Health & Wellbeing regularly through the year in Camberwell, London. See my website for further details.

I'd love to hear from you

If you've found mindfulness or yoga to help with negative feelings or moods, I'd love to hear your experience. Leave a comment below, join the discussion. 

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