His latest study included 34 Iraq and Afghanistan veterans, half of them with PTSD. They all got functional MRI scans, which track blood flow in the brain to show which areas are using the most oxygen, a sign of increased activity.
The researchers saw that among the PTSD group, who were all taking the drug paroxetine (sold as Paxil), the patients who showed the most improvement from the SSRI were those who showed the least activation, prior to treatment, of a brain area called the right ventrolateral prefrontal cortex, also known as the inferior frontal gyrus. The region is known to help with emotional regulation.
This area of the brain serves as a rational counterbalance to parts of the brain that generate raw emotion. It helps with tasks like impulse control, cognitive flexibility, and executive function. “These are all ingredients of emotional regulation,” said Phan.