The team separated studies by type of control group: trauma-exposed (those who had experienced trauma but did not have a diagnosis of PTSD) and trauma-naïve (those who had not experienced trauma), and compared the individuals with PTSD to both groups. This yielded an insight into how the abnormalities in functional brain activity in PTSD comprise a whole-brain network.
The analysis showed that there were differences between the brain activity of individuals with PTSD and that of the groups of both trauma-exposed and trauma-naïve participants.
This suggests that even in the absence of symptoms, trauma may have an enduring effect on brain function. Critically, the research found that in parts of a region of the brain called the basal ganglia, brain activity was different when comparing people with PTSD to the trauma-exposed group.
The findings suggest that the transition to clinical PTSD could be linked with imbalances specifically in the basal ganglia – but linked with imbalances in a larger brain network. This view has been reinforced by new evidence uncovered by the team using whole-brain computational modelling of other neuropsychiatric disorders. This modelling showed that these disorders lead to specific imbalances in specific brain networks.