Obsessive-compulsive disorder (OCD) can show itself in many ways.
Growing up, Brisbane business consultant and author Peter Bell had all the traits that typically define OCD.
He was consumed with constant, intrusive thoughts that led to a debilitating cycle of behaviours.
For him, it was excessive cleaning and checking.
"No escape, is a word I like to use," Mr Bell said.
"I was in a constant state of anxiety."
"Like any mental illness, it has had a huge impact on my life. It is a genuine disease of the brain."
Five years ago at the age 38, he was diagnosed with OCD and started to manage the symptoms with medication.
"Life really did start again in a lot of ways," he said.
Mr Bell is among about 2 per cent of the Australian population who experience the disorder, commonly known as OCD, which is characterised by recurring, intrusive thoughts.
Many people with the condition spend an extreme amount of time engaging in repetitive actions or behaviours to try to mitigate their anxiety.
A potential cause found
The exact causes of OCD are not known, it has no cure and treatments are limited.
Researchers at QIMR Berghofer are trying to change that.
A new study, which examined the difference in MRI brain images between healthy volunteers and people with OCD, has found a likely cause.
Researchers discovered changes in how distinct brain regions communicate.
Lead researcher Dr Sebastien Naze said the results confirmed the disorder likely emerges from a "complex imbalance" that affects "signalling pathways deep within the brain."
"Participants with OCD were shown to have an imbalance affecting distinct pathways and regions of the brain, which are linked to emotion regulation and reward," Dr Naze said.
"This imbalance is believed to be a main driver and potential cause of OCD symptoms."
"We aren't the first researchers to find it but … this gives us some important clues about what's causing the disease and how these brain changes could be corrected to reduce OCD symptoms," he said.
'An absolute game changer'
QIMR Berghofer senior researcher Luca Cocchi called the findings significant, saying they would "guide the development" of more targeted and effective treatments.
"These findings are meaningful because they replicate previous results … they allow us to develop new interventions that are targeting this dysfunction in a precise and individualised fashion … and reduce the symptoms," Dr Cocchi said.
"Current drug interventions lack specificity and only meaningfully reduce symptoms in a portion of individuals with OCD."
Researchers will use the findings in clinical trials of brain stimulation therapies for OCD later this year.
"It will allow us to specifically target structure and pattern of connectivity between the different regions to restore or bring a healthy level of communication," Dr Cocchi said.
"Brain stimulation has proven successful in the treatment of depression, so we're hopeful that it may help in cases of OCD."
"It's not going to cure the disorder, but it could potentially reduce symptoms to the extent that people can enjoy a relatively normal life," he said.
Mr Bell said the study's results were a "huge relief".
"It is an absolute game changer for a person that's gone through life blaming themselves for their obsessive-compulsive disorder," Mr Bell said.
"To be able to see that it's actually a function of the brain and a chemical imbalance … it's an absolute huge relief."
Dr Cocchi said researchers also hoped the study would help reduce the stigma surrounding OCD.
"The stigma is significant and so knowing that there is a neurological basis to their behaviour will be a relief for [people with OCD]," he said.
"I think there is hope — of course science takes time, but I think we're making good progress."
