Adolescent girls who suffer traumatic stress undergo accelerated maturation in a brain region responsible for integrating emotions and actions, according to a new study which found that stress affects the brains of boys and girls differently.
Among youth with post-traumatic stress disorder, the study found structural differences between the sexes in one part of the insula, a brain region that detects cues from the body and processes emotions and empathy.
The insula helps to integrate one's feelings, actions and several other brain functions.
The study from the Stanford University is the first to show differences between male and female post-traumatic stress disorder (PTSD) patients in a part of the insula involved in emotion and empathy.
"The insula appears to play a key role in the development of PTSD," said Victor Carrion, professor at Stanford.
"The difference we saw between the brains of boys and girls who have experienced psychological trauma is important because it may help explain differences in trauma symptoms between sexes," said Carrion.
Among young people who are exposed to traumatic stress, some develop PTSD while others do not.
People with PTSD may experience flashbacks of traumatic events; may avoid places, people and things that remind them of the trauma; and may suffer a variety of other problems, including social withdrawal and difficulty sleeping or concentrating.
Prior research has shown that girls who experienced trauma are more likely to develop PTSD than boys who experience trauma, but scientists have been unable to determine why.
The research team conducted MRI scans of the brains of 59 study participants ages 9-17. Thirty of them - 14 girls and 16 boys - had trauma symptoms, and 29 others - the control group of 15 girls and 14 boys - did not.
The traumatised and non-traumatised participants had similar ages and IQs.
Of the traumatised participants, five had experienced one episode of trauma, while the remaining 25 had experienced two or more episodes or had been exposed to chronic trauma.
The researchers saw no differences in brain structure between boys and girls in the control group.
However, among the traumatised boys and girls, they saw differences in a portion of the insula called the anterior circular sulcus.
This brain region had larger volume and surface area intraumatised boys than in boys in the control group.
In addition, the region's volume and surface area were smaller in girls with trauma than among girls in the control group.
The findings were published in the journal Depression and Anxiety.