A new study of Japan tsunami survivors shows that post-traumatic stress disorder (PTSD) actually shrinks part of the brain. 

Agence France Press reports that scientists compared the brain scans of 42 healthy adolescents taken in other studies two years before the killer tsunami with images taken three to four months afterwards. 

Among those with PTSD symptoms, they found a shrinking in the orbitofrontal cortex, a part of the brain involved in decision-making and the regulation of emotion, said a study published Tuesday in the Nature journal Molecular Psychiatry.

“The changed volumes in the orbitofrontal cortex are correlated to the severity of PTSD symptoms,” author Atsushi Sekiguchi told AFP.

Previous studies had already suggested that PTSD patients undergo changes to the brain, but this is the first to pinpoint which part of the organ is altered by trauma.

Read the full story.