‘At the moment we have focused our work to two areas in the brain,’ says Dr Sylvia Gustin from Neuroscience Research Australia. ‘One is called the thalamus—the other is the prefrontal cortex.’
Described as the ‘border in the brain’, the thalamus acts as the gateway between the spinal cord and higher brain centres.
When you sustain an acute injury there is an opening in the thalamus for information to pass through from the affected body part to the brain.
‘This is very important because then we need to heal, we need to relax, we need to look after ourselves. After an acute injury is healed, we know that this border should actually close.‘
When researching people who experience chronic pain, Gustin identified a key neurological difference: the opening in the thalamus remains open long after acute pain is gone.
Gustin’s team found a decrease in the volume of the thalamus, resulting in a decrease of a specific neurotransmitter: gamma-aminobutyric acid, or GABA.
‘What this means,’ Gustin says, ‘is that in people with ongoing pain, this border is always open. Every signal gets amplified and it results in the experience of pain.’
Researchers also found people with chronic pain experienced a reduction in the volume of their prefrontal cortex—the region of the brain that is understood to regulate emotions, personality expression and social behaviour.
This results in a further decline in the neurotransmitter GABA.
‘Every emotion and every cognition is amplified. People with ongoing pain, they anticipate pain with a lot of fear and they worry a lot of the time, and they can’t dampen down these feelings because the prefrontal cortex has lost its ability to dampen down these thoughts.’
Anxiety, depression and suicidal thoughts can be big problems for those living with chronic pain, says Gustin.
‘Twenty per cent try suicide. A lot of clients who I see, they can’t stop their worrying, they can’t stop their anxiety, and they ask me why.
For many patients, what’s worse is the invisible nature of their condition.
‘You can’t see pain, and this is a very big thing for these people,’ says Gustin. ‘With my work, I can educate people that it’s a physical pain that results from subtle changes in the brain.’
According to Gustin, the research demonstrates that interaction between brain cells is damaged in the brains of people with chronic pain.‘It’s in an unhealthy way, and we can change that. The border, the thalamus, can actually close, and we can do that with neuro-feedback. ‘We can change the way the cells talk to each other and we can actually rewrite the painful memories.’
The importance of perception
‘If we give people [with osteoarthritis] pictures of their hand at different sizes and we say ‘please pick out which one best represents your hand’, they will choose the image that is significantly smaller. ‘That suggests that there is alteration in their perception of the size of their body part.
‘But it’s not limited to that—we also see problems with their perception of touch. They are not very good at localising where they are being touched and they are not very good at localising where that body part is located in space.’Stanton says these tests suggest people with chronic pain process location-specific information differently.
This is similar to the proprioception problems common with EDS.
‘The tack I have taken has been saying: if we have these altered perceptions in people with pain, what if we actually target these perceptions directly?’
How to talk about pain
Toby Newton-John, a clinical psychologist at the University of Technology in Sydney, says the social dynamics around chronic pain can have a ‘very large influence’ over patients’ future expressions of pain.
While a partner can inadvertently increase a patient’s disability by providing excessive practical help, Newton-John says continued emotional support remains crucial to people living with chronic pain.
The clinical psychologist says it’s helpful to move away from constant discussion about the pain to expressing broader care and concern for that person as a whole.
This isn’t the first time this topic has come up here:
- The deadly effects of untreated or under-treated pain
- The Long-Term Effects of Untreated Chronic Pain
- Severe Chronic Pain is a Killer, Literally