CTE
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Chronic Traumatic Encephalopathy (CTE) is a degenerative brain condition linked to hundreds or thousands of head knocks over many years.
What is CTE?
We cannot diagnose CTE in living people yet. At present, the only way to confirm CTE is after death, through a brain examination. Most people who experience hundreds of head knocks over a lifetime, will not develop CTE.
Inside the brain, these repeated knocks can sometimes cause a build-up of a protein called tau. Tau proteins are normally part of a healthy brain, but when they clump together in the wrong places, they can disrupt how brain cells communicate and eventually cause those cells to die. Over time, this build-up can spread through the brain, leading to changes in thinking, mood, and behaviour.
CTE has mainly been studied in former professional athletes in high-contact sports (like American football and boxing), where repeated head knocks over many years are common. Scientists are still learning about how common CTE is, who is most at risk, and what factors may protect against it. Research is ongoing worldwide including leading research occurring here in NZ.
Most people who experience repeated head knocks will not develop CTE.
Long-term effect of repeated head knocks
Dr Helen Murray explains what happens to our brains when they are exposed to repeated head impacts over a lifetime.
Symptoms of CTE
Changes in mood, thinking, or behaviour have been linked to CTE. These symptoms, however, can also be caused by many other conditions such as depression, stress, ageing, dementia, or other health issues. Having these symptoms does not mean someone has CTE.
What this means
Prevention matters most
Reducing the number of repeated knocks to the head over many years will help reduce your risk of CTE. In contact sport, this may mean delaying the age at which your child starts tackle sport or reducing the number of tackles at training. There is no clear indication of number of head knocks as everyone is different but the fewer knocks over fewer years will reduce your risk.
Support is available
If you or someone you care about is worried about memory, mood, or behaviour changes, it’s important to talk to a doctor. There may be another medical cause of your symptoms, and it is important to eliminate this first. Early support can make a big difference regardless of the cause.
Research is hopeful
Scientists are working hard to understand CTE better, improve diagnosis during life, and find effective treatments.
You can take
action now
There are no current proven treatments for CTE but there is a lot that you can do in your daily life that has been proven to help delay the progression of CTE and contribute to overall brain health. Looking after your brain is about more than preventing CTE – it also helps with long-term wellbeing, and quality of life.
If you are concerned you have CTE, you can take steps to delay progression and help with brain health:
Avoid repeated knocks
Follow safety guidelines in sport and recreation. Never ignore or “play through” a head knock.
Respect recovery time
After a concussion, give your brain the rest and gradual return it needs. Going back too early can increase risks.
Stay physically active
Regular aerobic exercise supports blood flow and brain repair.
Look after your mental health
Managing stress, seeking help for low mood, and staying socially connected all protect brain health.
Prioritise sleep
Quality rest is vital for the brain to heal and clear toxins.
Keep your brain stimulated
Lifelong learning, puzzles, reading, or creative activities help keep thinking skills sharp.
Protect overall health
What is good for your heart, is good for your brain. Managing blood pressure, eating a balanced diet, and avoiding smoking or heavy alcohol use all reduce risks for the brain.