We all know chronic pain brings with it a hefty emotional toll. And we know that chronic pain does alter our neurotransmitter balance.
A study from UNSW Sydney and NeuRA (published in the European Journal of Pain) found that people with chronic pain also have a specific imbalance of neurotransmitters in the part of the brain responsible for regulating our emotions.
In fact, it may be responsible for our inability to keep our negative emotions under control. They suggest that it is persistent pain itself that is causing the chemical disruption.
“Chronic pain is more than an awful sensation,” says senior author of the study Associate Professor Sylvia Gustin, a neuroscientist and psychologist at UNSW and NeuRA. “It can affect our feelings, beliefs and the way we are.
“We have discovered, for the first time, that ongoing pain is associated with a decrease in GABA, an inhibitive neurotransmitter in the medial prefrontal cortex. In other words, there’s an actual pathological change going on.”UNSW
Some neurotransmitters amplify signals to communicate messages between cells (excitatory neurotransmitters). While others weaken signals of these messages (inhibative neurotrasmitters)
GABA is a main inhibitory neurotransmitter of the central nervous system. Specifically, it has a role in the medial prefrontal cortex which is a part of the brain where our emotional regulation occurs. GABA helps dampen our emotions. When GABA is decreased our actions, emotions and thoughts, well, get Amplified.
The study looked at the medial prefrontal cortex of 48 patients (half of which had chronic pain) to look at the GABA content there. These sorts of brain scan studies all tend to be small due to the cost factor.
Those with chronic pain showed significantly lower levels of GABA than the control group regardless of the type of chronic pain.
“A decrease in GABA means that the brain cells can no longer communicate to each other properly,” says A/Prof. Gustin.
“When there’s a decrease in this neurotransmitter, our actions, emotions and thoughts get amplified.”
While the link between chronic pain and decreased levels of GABA has previously been found in animal studies, this is the first time it’s been translated to human studies.
A/Prof. Gustin says she hopes the findings are encouraging for people with chronic pain who may be experiencing mental health issues.
“It’s important to remember it’s not you – there’s actually something physically happening to your brain,” she says.
“We don’t know why it happens yet, but we are working on finding solutions on how to change it.”UNSW
This is pretty fascinating and also sometimes when it feels like I am literally fighting a war with my brain maybe it is because I am. It is difficult with pain to constantly confront negative thoughts and thinking even when we develop the tools to do so.
Previous studies they have done have shown this is not the only neurotransmitter affected by chronic pain.
In a previous study, A/Prof. Gustin and her team found that levels of glutamate, the main excitatory neurotransmitter in the central nervous system, are also lower than average in people with chronic pain. These low glutamate levels were linked to increased feelings of fear, worry and negative thinking.
“Together, our studies show there’s really a disruption in how the brain cells are talking to each other,” says A/Prof. Gustin, who has been researching chronic pain for over 20 years.
“As a result of this disruption, a person’s ability to feel positive emotions, such as happiness, motivation and confidence may be taken away – and they can’t easily be restored.”UNSW
I have talked about research showing that our motivation is affected neurologically and that alone can have a real effect on our capacity to cope, to set goals, to achieve goals, and to feel accomplished when we do attain goals.
“Everything starts with stress,” she says. “When someone is in pain, it increases stress hormones like cortisol, which can trigger massive increases in glutamate. This happens during the initial, acute stage of pain.
“Too much glutamate can be toxic to brain cells and brain function. We think this disruption to normal brain function may cause the GABA and glutamate levels to change – and impair a person’s ability to regulate their emotions.”UNSW