How are pain and the brain related?

There is a complex relationship between peoples mental and physical health including pain.

The experience of pain is generated in the brain by a combination of information from our nervous system, other senses, our existing knowledge, previous experiences and general context. Studies have shown that pain and emotions are processed in the same part of the brain so there is close relationship with how you feel emotionally and your pain experience.

When we start to talk about the brain in relation to pain, some may worry that professionals or others around them are inferring that the pain is “all in your head”. The brain is involved in the experience of pain because the body and brain are connected. All nerves from the body send messages to the brain including signals about potential threat; the brain processes all the information and ‘decides’ on what you need to know or feel or do. There are no pain nerves, pain centres or separate pain pathway. As well as the nervous system, the brain takes in information from other senses (touch, smell etc.) previous memories, fears and beliefs about the sensations experienced and the current situation. This guides how you respond to this experience an could result in an output of pain.
It is important to note that your experience of pain is very much real however it can be beneficial to consider additional factors that impact your experience of pain.

The Brain and Body Connection

We have evolved to have an amazing sensory system which is constantly detecting even the smallest of changes in the body and letting the brain know about them. It is important to note that almost all of the time, the brain responds without us ever being conscious of this, this means that we may need to develop an awareness of when this may be happening. Throughout our entire nervous system there are millions of sensors which are constantly looking out for activity. These are located in the walls and at the end of individual nerve cells (neurones).

Sensors can be specialised; some respond to mechanical forces (pinch, pressure) some temperature (hot and cold), some chemical changes both outside your body (e.g. nettle stings or allergens) and inside your body (e.g. chemicals released by cells such as lactic acid when you exercise). They enable the neurones to provide information to the central nervous system (spinal cord and brain). There are some neurones in the tissues called nociceptors which respond to lots of different stimuli if those stimuli are enough to have a potential threat to the tissues.

Sometimes it is helpful to think of pain as a sophisticated alarm system which works by detecting changes that are big enough to be a potential threat and tells us where in our body this is, how much potential threat there is and the nature of it (e.g. a burn compared to a pinch) and sends this information to the spinal cord, which then if it meets the threshold needed will send the information on to the brain which decides how to respond depending on all the other information it has available including our senses, memories, and the general context we are in. We all have this happening almost all the time, but it only results in pain some of the time. For example the pressure on our bottoms when we are sitting down will send messages to the spinal cord which might lead us to take some sort of action like wriggling or changing position without our bottom actually hurting.

We can all relate to having immediate reactions to certain things and to mulling over things in our mind; what is significant is how we then respond to those reactions in our bodies. We are remarkably complex beings and our brains have evolved to enable us to think flexibly, engage in meaningful conversations and form connections with others. Developments in neurophysiology and neuroscience have taught us that the evolution of the brain is key to understanding the relationship between the brain, mind, and body.

Cognitive research has highlighted the complex systems and higher order processes within the mind and shown that our brain is hard wired to be responsive to threat. This serves the evolutionary function of keeping us protected from harm. To make sense of a vast array of information our brains use short cuts to select the most important information. Whilst this automatic process serves us well from a survival point of view, our default ‘negativity bias’ can lead us into ways of thinking that can be detrimental to our health and wellbeing. We are drawn to negative thinking patterns, worries and catastrophising. Most of our thoughts are automatic, and we are more likely to repeat a thought we have had. We know that thinking patterns are linked to our mental health which is why therapies have been developed with the specific aim of changing a person’s thinking habits.

We are designed to learn how to respond emotionally to things. Simply having the thought about something negative can lead to a physical response (e.g. increased heart rate, headache/tension in the body) and an emotional response (e.g. stress/worry/dread). Ruminating about a thought can lead to ongoing stress and fatigue. Emotional and physical responses can influence the overprotective alarm system and potentially lead to an increase in your experience of pain.

The Role of our Thoughts

We have 6,000 thoughts per day, 5,000 of which are the same as those we had yesterday. It’s likely that when we have pain, we have even more. So we are creatures of habit, with the same thoughts day in, day out. Our brains can create patterns and pathways associated to many things, including pain pathways, these patterns become easier to access the more they are repeated, these patterns might have been helpful for us in situations in the past but may not be helpful in the present day.

It is the nature of the human mind that we tend to have more negative judging thoughts than positive, compassionate ones. Our mind is a ‘be safe machine’, so it’s designed to look out for danger, what might go wrong next? Each time we have a negative thought it becomes easier to have it the next time. For instance if we keep having the judgemental thought “I’m useless I can’t even wash up properly”, the next time we see a washing up bowl we will automatically have the thought “I’m useless” without us even being aware of it. We can increase our awareness of our thoughts by using techniques like Mindfulness (INSERT MINDFULNESS LINK) which can help identify which thoughts may be impacting your experience of pain.

We can all have unhelpful thinking styles which can exacerbate our distress. More information can be found here:
https://www.getselfhelp.co.uk/docs/UnhelpfulThinkingHabitsWithAlternatives.pdf