Increased circuit activity in the right side of the brain triggers involuntary flashbacks in post-traumatic stress disorder (PTSD) sufferers, researchers said.
All participants were required to wear the MEG (Magnetoencephalography) helmet while fixating on a spot 65 cm in front of them for 60 seconds.
The researchers found a difference between communication in the temporal and parieto-occipital right hemispheric areas of the brain. The temporal cortex, in accordance with earlier findings on the effects of its electrical stimulation during brain surgery, is thought to be responsible for the re-living of past experiences.
They also found that the brains of the sufferers were in this hyperactive state despite no immediate external stimulation, as the trial subjects were purposefully put into a 'task-free state'.
"Remarkably, the differences we found between the PTSD and the control groups were documented in a task-free state. Without evoking traumatic experiences, and, therefore, reflects the status of steady-state neuronal interactions," the researchers wrote.
The findings are published today in Journal of Neural Engineering.