How phobias can be ‘switched off’
FEARS of flying, being attacked by a dog or being afraid of creepy crawlies can be "switched off", groundbreaking Queensland research has revealed.
In a newly-released Nature Neuroscience report, UQ researchers at Queensland Brain Institute reveal they have discovered a DNA modification that enhances the ability to "extinguish fear," particularly if someone has experienced a traumatic experience.
Researchers say fear extinction works as a counterbalance to fear, where it involves the creation of new non-fearful memories with similar environmental elements that compete with the original fear memory.
Professor Tim Bredy at QBI said that while fear is an important survival mechanism which keeps people safe and away from danger, there is an ability to inhibit fear when it's no longer needed.
"You still want to have that memory of 'there's something dangerous there, I want to be careful,' but you don't want it to compromise your ability to function normally," he said.
DNA modification in general are chemical tags that are added on our DNA, by adding them or taking them off, it controls how genes respond to environment changes, learning and memory processes.
QBI researcher Dr Xiang Li said by altering the modification, researchers can control gene responses in either cell or animal model.
"Under fear extinction processes, there could be many different DNA modifications working together controlling gene response and promoting memory formation," he said.
"Within this study, we found out a new DNA modification that could promote gene response and drive the ability for us to extinguish the original fear memory.
He said the research has taken about five years, and will ideally result in a new therapy, like a drug in the years to come to help people suffering from fear-related anxiety disorders.
"We're not trying to disturb the normal fear memory stored in the brain, but those abnormal experiences for example child abuse or a bite from a dog so that actually affects people's lives," he said.
"The main thing is it's not changing the fear memory but using different memories, or new memories to inhibit the fear memories."
His example was if a surfer got attacked by a shark, the DNA modification could help them feel safe to get back into the water, or could help people with common fears like public speaking, flying or snakes.
Dr Li said the research would not create fearless people, and would still leave nervousness and bad memories in the brain, but would promote extinction fear memories that come through stronger than previous uncomfortable memories.
Ultimately, the researchers hope to understand the full picture of how fear extinction memory is formed and stored in the brain.
This report was an "important step" toward finding effective treatments for a variety of psychiatric disorders.