Ascellus Blog

Good Brain, Bad Brain and Pain

October 3, 2017

Understanding how the brain functions with pain

Ever wonder why someone with an injury on one side of his body suddenly develops pain on the other side? Or why pain persists even when all medical evidence shows the affected tissues have healed? Some might say it’s all in the person’s head — and they’d be right, in a sense.glass_skull_four_lobes_400_clr_6671

It’s actually certain areas of the brain functioning on overload and shutting out the rational, thinking part. It can cause a person’s immune system to turn against itself and rather than being anti-inflammatory, it causes increased inflammation — and pain. By understanding how the brain works, injured workers can mitigate and even prevent chronic pain from taking over their lives.

Good Brain and Acute Pain

The brain is an amazing machine. It takes in all the stimuli around us, analyzes it and determines the best course of action. It’s what I call ‘good brain.’ Here’s how the good brain handles pain.

Say you accidentally put your hand on a hot pan. The pain sensation you feel travels up the peripheral nerve, through the spinal cord to the primal brain, which is the source of the fight-flight-freeze survival response system. The primal brain sounds the alarm and sends the fight-flight-freeze response to the body area that needs to respond; in the example, that would be your hand.

The primal brain also sends the alarm signal to higher levels of the brain; the emotional brain (the limbic system) and the thinking brain (the pre-frontal cortex). The emotional brain analyzes the current threat against past threats; basically, memories of similar threats experienced earlier in life, and it ‘codes’ the threat. It then sends it to the thinking brain with a threat level code. This highest level brain function analyzes the input and decides what action to take.

The thinking brain can override the primal and emotional brains’ assessments of the situation. In the example, let’s say there was a child standing right beneath where our hand was holding the hot pan. While the primal brain is saying ‘drop the pan immediately to protect your hand,’ the thinking brain says, ‘protect the child, then release the hot pan.’

The good brain functions to keep us safe while still allowing us to make choices beyond just operating in survival mode.

Bad Brain and Chronic Pain

Problems can arise when pain persists even though there is no immediate threat to the body. The primal and emotional brains are sending the alert signals and the thinking brain is not overriding them.

Consider this; we know that often movement is the best remedy for an injury even though it may be painful. Returning to work, for example, can help the physical healing process. Even though moving causes us some pain, our thinking brain takes over and allows us to keep moving, or working, and eventually the pain lessens or goes away completely. In this case, our thinking brain understands this.

But an injured worker with persistent pain who does not understand this becomes afraid that movement could cause more damage and worsen the pain. When brain and body response keep going and going and the fight-flight-freeze response continues over a long period of time, changes start to happen in the brain, the spinal cord and the tissues.

Gradually, the primal and emotional brains literally occupy more space in the brain and continue sending pain alerts. It can cause the pain to grow, or migrate to the other side of the body. This is chronic pain. It is also the beginning of what I call ‘bad brain,’ when the primal and emotional brains have hijacked the brain and we are operating strictly in survival mode.

The responses that made sense for acute pain don’t make sense for chronic pain. Eventually, the body’s response system starts to turn against the constant alarms and gets pain fatigued. This affects the immune system, which turns against itself, leading to exacerbation of the pain — even when the affected tissues have recovered.


Bad brain can continue on endlessly. Typically, the affected injured worker seeks out medical remedies for his pain, such as surgeries, opioids, or experimental treatments. When none of those solutions works he may delve into disability mindset and think he is a lost cause.

But we know that injured workers in this predicament can be helped, can get back to function and even return to work. Understanding how the brain functions with pain is the first step in the process. Once there is this understanding, the injured worker can participate in, and respond to cognitive behavioral therapy and other techniques that give him tools to control his own pain.

Ascellus is a national network of Health Providers in Psychology that delivers CBT for chronic pain, trauma and insomnia across the country for the workers’ compensation industry.

For additional information, contact us at The ‘Up pain, Down Pain, Good Brain, Bad Brain’ adult coloring book is available for download at in the Education tab.

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Ascellus bridges the gap between mental and physical health to accelerate recovery for our nation's workforce. By connecting the workers' compensation industry with our expert behavioral care and evidence-based treatments, we deliver high-quality outcomes, helping injured workers reemerge with increased strength, purpose and resilience in the workplace.