The need to protect children from traumatic events has been brought into sharper relief than ever by the results of a new study, which illuminates how the brains of kids with post-traumatic stress disorder (PTSD) differ in both structure and function from those without the condition.
Despite its overwhelming complexity, the human brain is in fact incredibly well organized. In simplified terms, it consists of a number of regions, also known as nodes, that communicate with one another via connections called edges. To ensure that this communication is as efficient as possible, these nodes are arranged in what is known as a “small-world network”, meaning that they are all connected to each other by the minimum number of steps possible.
However, the new study – which appears in the journal Radiology – reveals that this small-world network is disrupted in children with PTSD, as communication between nodes becomes less direct and brain activity becomes more localized rather that “global”. In other words, brain regions lose the ability to efficiently communicate with other distant regions – a process known as regularization.
To conduct their research, the study authors used MRI to scan the brains of 47 children that had experienced the Sichuan earthquake, which killed nearly 70,000 people in 2008. Half of these children had been diagnosed with PTSD while the other half had not.
Comparing the two groups, the researchers discovered that those with PTSD showed higher levels of regularization, with brain signals between nodes having to travel along longer paths, resulting in a decrease in efficiency.
In particular, this occurred in a series of nodes that collectively make up the salience network, which plays a role in regulating attention. Similar levels of regularization were also observed in the central executive network, which contains the superior parietal gyrus, where fear responses are regulated. This, the researchers say, could explain the anxiety that PTSD sufferers tend to experience.
Given that the brain undergoes major development during childhood and adolescence, anything that alters neural structure and function at this time could potentially have major consequences, which is why the results of this study are not to be taken lightly.
While there is currently no cure for PTSD, the researchers suggest that developing new treatments that target the salience network could one day help to alleviate the symptoms of the condition.