There’s a reason why people with PTSD relapse after treatment, and it’s to do with the brain
Cognitive behavioural therapy (CBT) is often hailed by health professionals as the great pillar of psychiatry. In the UK for example, CBT was revealed to be the most common form of therapy, accounting for 38% of appointments in the UK in 2014. The thing is though, CBT has a patchy record of dealing with trauma, where relapses are common. And thanks to a new study from scientists at the Queensland Brain Institute, we may have a better understanding as to why.
CBT often uses something called exposure therapy to help treat disorders like post-traumatic stress disorder (PTSD), which involves the patient being exposed to the trigger in a safe setting using extinction training.
“This procedure aims to uncouple a stimulus from triggering a response, in this case fear,” said one of the lead researchers, Dr Roger Marek.
Looking at the neurology of how we unlearn fear, the scientists observed what happened in the brains of mice and rats in learning and unlearning fear, and evaluated the neural pathways in the hippocampus, crucial for memory storage.
They expected to see the neural pathways stop working, as previous relapse models have shown, but they actually saw something completely different. The researchers saw that fears were resurfacing because they grew another bridging neuron that linked the hippocampus to the infralimbic cortex. In other words, the brain physically grew another pathway.
“Despite the success of these treatments in providing therapeutic relief to patients, extinction training does not totally erase traumatic memories, but rather suppresses its expression,” Malek added. “Previous research in both rats and humans has found that the fear ‘relapses’ under certain circumstances”.
While the neuroscientists don’t have a therapeutic solution for treating these neural circuits, they hope that the knowledge will open the doors to new therapies that could help treat trauma-related conditions like PTSD in the future. And at least it gives therapists an understanding as to why PTSD relapses are so frequent despite counsellors best efforts.